FR2658320A1 - PHOTOGRAPHIC APPARATUS COMPRISING ZOOM FUNCTION WITH MID-EXPOSURE. - Google Patents

Abstract

It is a camera (10) which has a zoom function at half exposure and which includes a zoom motor for driving a zoom lens (13), a switch for triggering the adjustment of the zoom lens at mid -exposure and a means of executing the operation of adjusting the zoom lens at mid-exposure to start driving said zoom motor on the basis of actuation of the trigger switch to start an exposure.

Description

1 2658320

PHOTOGRAPHIC APPARATUS COMPRISING

A ZOOM FUNCTION WITH MID-EXPOSURE

  The present invention relates to a camera comprising a motorized zoom lens and, more particularly, to a camera comprising a zoom function at mid-exposure, that is to say a camera comprising a zoom function which

  can be active at the time of exposure.

  Performing a mid-exposure zoom is a shooting technique in which the focal length is intentionally changed during the duration of an exposure to achieve a particular effect of representing a captured motion in its speed by using the mechanism of the variable focal length that is characteristic of the zoom lens Images taken with an exposure zoom present a picture blur due to the change of the focal length during the exposure. This mid-exposure zoom operation is performed during the exposure time, so its results depend on the shutter release timing, the preset shutter speed, a manual shutter speed setting, and the shutter speed. zoom execution and so

right now.

  The operation is therefore based on "know-how" (or

"intuition") of the user.

  In a camera that has a motorized zoom lens, that is, a zoom lens that uses drive power to adjust the zoom lens, such a mid-exposure zoom lens adjustment operation may be done with some ease, but the camera is not designed to coordinate the exposure and adjustment of the zoom lens in a coordinated manner, so a technical skill based on technical know-how is required. shutter release while simultaneously operating the power zoom switch so that it is turned ON. As a result, the use of such a type of camera is hardly more convenient than the use of the camera. the type of camera that has a zoom function in manual mode. It is, therefore, an object of the present invention to provide a camera which allows adjustment of the zoom lens to be magnetically displayed.

  automatic and reliable by simple manipulation.

  The present invention includes a zoom motor for driving the zoom lens, a trigger switch for initiating the mid-exposure zoom lens adjustment operation, and a means for performing the zoom motor drive. zoom to start the exposure operation in accordance with the action of this

trigger switch.

  This arrangement allows the user to perform the operation of setting the zoom lens at half exposure automatically and to expect reliable results, this is not based on the technique of the user. Said means for executing the adjustment operation of the mid-exposure zoom lens comprises the means for starting the zoom lens setting and the

  way of starting the exhibition.

  Further, in accordance with an aspect of the present invention, means are provided for detecting a condition sufficient to enable the exposure start means to start the exposure in synchronism with the operation of the start-up means of setting the exposure. zoom lens This arrangement allows the user to manually and easily perform the adjustment operation of the zoom lens at mid-exposure and also allows him to initiate the exposure operation after the stabilization of the displacement due to to the adjustment of the zoom lens to optimize the desired effect The means for executing the adjustment of the zoom lens to the exposure comprises: a means for starting the zoom lens adjustment, a means for starting the zoom lens; exposure, a counting means for counting the exposure time after actuating said zoom lens setting start means, a means for reading a shutter speed and a servo means t stopping the rotation of the zoom motor when the counting value obtained by said counting means has reached a predetermined ratio in a global time of exposure, this allowing the user to perform with ease the manual control of the operation of adjusting the zoom lens to the exposure and automatically stop the zoom lens adjustment operation before the end of the exposure. The means for enabling the mid-exposure zoom lens adjustment operation to be performed preferably comprises: focal length detecting means, focal length memory means for storing the zoom data, focal length both at the beginning and the end of the zoom lens adjustment operation, respectively; means for reading the shutter speed and motor speed control means for controlling the zoom motor driving speed, whereby it is possible for the user to perform manual control of the mid-exposure zoom lens adjustment operation and set the zoom lens adjustment speed appropriately according to the result of the comparison between the focal length and shutter speed, an image of uniform density and

  invariable that can be formed.

  In another aspect of the present invention, the means for performing the mid-exposure zoom lens adjustment operation further includes a focal length detecting means for detecting a change in the value of the zoom lens. of the focal length, a comparison means for comparing the focal length variation that has been detected with a focal length rate of change, a motor speed control means for controlling the rotational speed of the motor according to the comparison results delivered by this comparison means, where it follows that it is possible for the user to perform with ease the operation of adjusting the zoom lens to the exposure for the purpose of maintain constant focal length variation while performing a zoom lens adjustment operation, an image of uniform density

thus be obtained.

  In yet another aspect of the present invention, the means for performing the mid-exposure zoom lens setting operation further includes a focal length memory means for storing the focal length data. and motor control means which serves to stop the zoom motor when it reaches a defined focal length in order to stop the adjustment operation of the zoom lens as stored in this memory means and thus allowing the user to easily perform the manual control of the mid-exposure zoom lens adjustment operation and to stop the zoom lens adjustment operation to any focal length which was chosen to complete the zoom lens adjustment operation after confirming the focal length by looking into the viewfinder, for example. This also allows the user to imagine the photograph in the camera. form

  before actually taking it.

  Further, in accordance with an aspect of the present invention, the means for executing the mid-exposure zoom lens setting operation further comprises shutter speed memory means for storing the speed. shutter mode and a zoom lens setting initiation limiting means for operating the mid-exposure zoom lens setting operation only when the shutter speed is lower than a shutter speed. pre-established reference shutter, which has the effect of allowing the user to easily perform a manual control of the adjustment operation of the zoom lens at mid-exposure and to limit the adjustment operation of

  the zoom lens at mid-exposure to slot exposure.

  This also serves to prevent the possibility that the image

  obtained has an irregularity of the exposure.

  Furthermore, if the camera of the invention includes the half-exposure zoom lens setting mode in which the zoom lens adjustment operation is operated during the exposure and includes a modification of the zoom lens. zoom adjustment speed in response to the variation of the value F of the diaphragm caused by the zoom adjustment operation, then the risks of an exposure irregularity in the image obtained are avoided, in the case where the operation of Mid-exposure zoom adjustment is performed using the zoom lens whose F-iris value varies according to the zoom setting. The object of the invention in one of its aspects is to create a camera which has a function of adjusting the zoom lens at mid-exposure and which is intended to allow the user to easily perform a command Manual of the mid-exposure zoom lens setting operation including a zoom motor which drives a zoom lens, a trigger switch for triggering the mid-exposure zoom setting, a means for starting the zoom adjustment for starting the zoom motor drive based on actuation of the trip switch, an exposure start means for starting the exposure based on the operation of the start means of the setting of the zooming motor; the zoom lens, and a counting means for counting the exposure time in synchronism with the operation of the zoom lens setting start means, the exposure start means initiating the exposure when the counting means has counted a predetermined time The aforesaid predetermined time is advantageously a period during which the speed of adjustment of the zoom lens becomes constant This time will be set for example to 1/10 of the overall exposure time A button of triggering can be advantageously provided as a means of starting

of the zoom lens setting.

  The purpose of the invention in one of its aspects is to create a camera which has a function of adjusting the zoom lens at mid-exposure and which comprises: a zoom motor which serves to drive a zoom lens, a means for storing a preset shutter speed, means for executing adjustment of the magnifying zoom lens which serves to drive the zoom motor and to start the exposure, a counting means for counting the time in synchronism with the operation of the mid-exposure zoom lens setting means, and means for stopping the zoom lens setting operation to stop the zoom operation. zoom engine when a value counted by the counting means reaches the predetermined rate of the overall exposure time corresponding to the shutter speed stored by the shutter speed memory means. This predetermined rate of the overall time of the shutter Exposure may be 80% of the overall exposure time The camera may also be equipped with a shutter speed selector to be entered in the means for storing a speed.

shutter preset.

  The invention further provides a camera with a zoom lens adjustment function at mid-exposure and which comprises: a zoom motor for driving a zoom lens, a focal length detecting means for detecting the zoom lens; focal length of the zoom lens and which includes a memory switch, a mid-exposure zoom lens setting medium which serves to drive the zoom motor and to launch the exposure, a means of Focal length memory for storing a focal length at both the start and the completion of the zoom lens adjustment operation, means for reading a preset shutter speed and control means the speed of the motor which is used to control the zoom motor drive speed based on the focal length data from the focal length memory means and the shutter speed from the

  shutter speed memory means.

  The purpose of the invention in one of its aspects is to create a camera which includes a function of adjusting the zoom lens at mid-exposure and which comprises: a zoom motor which drives a zoom lens, a medium executing adjustment of the mid-exposure zoom lens which drives the zoom motor and initiates the exposure, a focal length variation means for detecting a focal length variation value achieved by the zoom lens , a comparison means for comparing a value indicated by the variation detection means with the predetermined rate of change of a focal length and an engine speed control means which is used to control the speed of rotation of the zoom motor. on the basis of the result of the comparison made by the comparison means so as to maintain at a constant value the rate of change of focal length when adjusting the zoom lens The speed control means of the motor increases the rotation speed of the zoom motor when the change in focal length detected by the focal length variation detecting means is greater than the predetermined focal length variation rate and decreases the zoom speed of the zoom motor when the focal length variation detected by the focal length variation detecting means is less than the

  predetermined variation in focal length.

  The invention in one of its aspects also proposes a camera which includes a function of adjusting the zoom lens at mid-exposure and which comprises: a zoom motor for driving a zoom lens, a means for executing a zoom lens; adjustment of the zoom lens to the exposure which is used to drive the zoom motor and to start the exposure, a memory means which is used to memorize the focal length at the time of the completion of the zoom lens setting and a means motor control system for stopping the zoom motor when the focal length reaches said focal length at the time of completion of the zoom lens setting as stored in the focal length memory means during lens adjustment Mid-exposure zoom This apparatus may advantageously further include a memory switch, the operation of the focal length memory means being based on the operation of this memory switch. According to one of its aspects, the invention further proposes a camera with a function of adjusting the zoom lens at mid-exposure and which comprises: a zooming motor which serves to drive a zoom lens, a means of memorizing a preset shutter speed, a means for executing the mid-exposure zoom lens setting operation which serves to drive the zoom motor and to start the exposure and a means for limiting the start of the exposure. zoom lens adjustment operation that serves to enable the start-up operation of the mid-exposure zoom lens adjustment operation operation only when the shutter speed is slower

  that the standard shutter speed predetermined, that

  It can also be a synchronous contact speed X. The invention also provides a camera with a mid-exposure zoom lens adjustment function, this apparatus having a motorized zoom function, and comprising: a mid-exposure mode which is used for adjusting the zoom lens during the exposure operation and control means for varying the speed of the zoom lens adjustment during exposure according to the iris variation caused by the adjustment the zoom lens The adjustment speed of the zoom lens is then advantageously set so that it increases when the adjustment of the diaphragm corresponds to a clear time and slows down when the adjustment of the diaphragm

corresponds to cloudy weather.

  This description refers to the content

  Japanese Patent Applications No. 02-33003, No. 02-33004, No. 0233005, No. 02-33006, No. 02-33007, No. 0233008,

  No. 02-33015 (all filed February 14, 1990).

  The characteristics and advantages of the invention

  will emerge from the following description at

  by way of example with reference to the accompanying drawings in which: Fig. 1 is a block diagram showing a control circuit of the camera in accordance with an embodiment of the invention, Fig. 2 is a plan view of 3 is a corresponding view in side elevation; FIG. 4 is a simplified view showing the actuating mechanism of the powered zoom lens; FIG. 5 is a cross-sectional view showing a main part of the motorized zoom lens on a partially enlarged scale, FIG. 6 is an enlarged cross-sectional view showing the construction of the mode switch Pz, FIG. 7 is an enlarged view of the coding plate in which the setting positions are read. of, the zoom lens, Fig 8 is an enlarged view showing the input substrate controls, Fig 9 are there are flowcharts that show the operation of the first mode of realization 12 is a flowchart showing a second embodiment of the invention, FIG. 13 is a block diagram showing a control circuit for a camera constituting a third embodiment of the invention, FIG. is a flowchart showing the operation of the third embodiment, Fig. 15 is a block diagram showing a control circuit in a fourth embodiment of the invention, Figs. 16 to 18 are flowcharts showing the operation of the fourth mode of operation. Fig 19 is a block diagram showing a control circuit in a fifth embodiment of the invention, Figs 20-22 are flow charts showing the operation of the fifth embodiment, Fig 23 is a block diagram showing a control circuit in a sixth embodiment of the invention, Figs 24 and 25 are diagrammatic DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 26 to 28 are flow charts relating to the operation of a seventh embodiment of the invention, FIG. 29 is a basic view of the electric zoom lens and its block of FIG. In the eighth embodiment of the invention, Fig. 30 is a graph showing the relationship between the rotational speed R of the zoom motor and the focal length F, and Fig. 31 is a graph showing the relationship between the width. of the focal length and a focal length in the eighth embodiment, Fig. 32 is a focal length scale corresponding to that of the graph of Fig. 31, Fig. 33 is a graph showing the relationship between the length focal length f and the aperture value of the diaphragm in a conventional zoom lens, and Fig. 34 is a view showing a focal length scale with the magnitude of variation of the focal length with respect to the angle of rotation. otation of the

zoom control ring.

  Figures 2 and 3 show a device

  photographic embodying the present invention.

  The camera (mono-objective SLR) includes an autofocusing device as well as an automatic exposure device in addition to one

motorized zoom lens.

  The body 12 of the camera 10 is provided on its front end with a zoom lens 13 and a gripping portion 14. On the upper surface of the body of the camera are arranged a

  shutter release switch (push button) -

  and a mode select switch (button) 16 for selecting the camera's shooting mode The shutter release switch 15 is connected to a SWS light measuring switch so that when the trigger 15 is half-pressed (first step) this

  Light measurement switch is set to ON.

  As shown in FIG. 4, the zoom lens 13

  comprises two sets of Li and L 2 lens groups.

  The first and second lens groups Li and L 2 comprise a plurality of roller pins 70 and 71 fixed on their outer circumference and forming a radial overshoot, these roller pins 70 and 71 engaging in cam paths 72 and 73. formed in a cam ring 19 At least one of the roller pins 70 and 71 engages in a linear guide path which is

  formed in a fixed lens tube 17.

  An annular gear 60 is fixed in position around the outer circumferential surface of the cam ring 19 and the pinion 61 of the zoom motor 4 meshes with the gear 60. The cam ring 19 is thereby driven to rotate at the same time. means of the zoom motor 4 to move the first and second groups of lenses Li and L 2 in the direction of their optical axis, which allows to create a zoom lens adjustment effect A decoder 67 is placed on the surface The outer circumferential ring cam 19 for detecting the position of the cam ring 19 and determining the focal length f. This decoder 67 consists of a coding plate 22 (FIG.

  7) and a coding plate broom 28.

  The signals that are extracted by the decoder 67 are delivered to the objective CPU 66. The objective CPU 66 determines a focal length f and its full aperture value of the corresponding diaphragm (minimum diaphragm value F) from the output of the decoder 67, these data then being communicated to the control section 1 of the body of the camera 12. There is also shown in FIG. 4 a zoom lens adjustment ring 75 intended to be used in a camera.

  manual operation of adjusting the zoom lens.

  The external stationary lens tube 17 comprises a wide-angle switch (button) 29, a tele-switch (button) 30, a start switch (button) 31 and a mode selection switch (zoom)

  electrical) Pz (button) 33 (fig 2 and 3).

  The wide-angle switch 29 and the tele switch 30 in Fig. 5 have springs which make them flexible and comprise conductive contact strips 29a and 30a at the location where they are opposed to an input substrate. Thus, when the wide-angle switch 29 is depressed, the conductive contact strips 29a come into electrical contact with the control input substrate 35 in order to place it ON, while the conductive contact strip 30a comes into electrical contact with the control input substrate 35 when the switch

TV 30 is depressed.

  The Pz 33 mode selection switch is used to switch a shooting operation between the PZ (power zoom) mode and the Exz (exposure zoom) mode, and the switch 33 can be operated by moving the Pz mode switch 33 in the forward and reverse directions to cause the coding plate brush 40 to contact the control substrate 35 to select

a functional mode.

  The control circuit of the camera 10 in the first embodiment of the invention will now be described with reference to FIG. 1. The trip switch 15, the wide-angle switch 29, the telly switch 30, the mode select switch Pz 33 and the mode select switch 16 are connected to the input of the control section 1 A solenoid 5 is connected to the output of the control section 1, this solenoid 5 actuating the motor 4 as well as the shutter The control section 1 comprises a mode selection means Pz 6, a mode selection means 7, a means start of zoom lens adjustment operation operation 8, exposure start means 9

and counting means 14.

  The mode selection means 6 has the role of switching the operating mode between the Pz mode and the Exz mode in response to an input signal from the

  Pz 33 mode selection switch.

  The function of the mode switching means 7 is to switch the operating mode to automatic delay mode, etc., in response to the input signal from

of the mode switch 16.

  The initialization means of the adjustment operation of the zoom lens 8 is to start a zoom lens adjustment operation by delivering a control signal to the motor 4 in response to an input signal from either a wide-angle switch 29

a television switch 30.

  The counting means 14 initializes its counting action in synchronization with the start of the zoom lens adjustment operation by the start-up means of the zoom lens.

  the adjustment operation of the zoom lens 8.

  The exposure initialization means 9 starts the exposure operation by delivering a signal to a solenoid when the preset time is exceeded after the counting operation has been started by the counting means 14. The preset time in question is the weather at

  during which the zoom adjustment speed becomes constant.

  This time can be set for example to 1/10 of the total exposure time. Figures 9 to 12 show the operation of the camera whose construction is such that

as described above.

  It is judged in a step 51 whether or not the SWS light measurement switch is ON If this is not so, the step S1 is repeated. The process proceeds to a step 52 when the switch is turned on. placed on

MARKET.

  It is judged at a step 52 whether the mid-exposure zoom lens adjustment operation is to be performed and the process if so advanced to a

  step 53 and if not so advance to a step 54.

  A photographic composition is determined during this period and the shutter speed is prepositioned by manipulation of the rotary switch of

the shutter speed.

  It is judged at a step 53 whether the value T v (shutter speed) is slower or faster than the synchronous speed of the contact X (synchronous speed of the flash), the process is repeated if the shutter speed is greater than the synchronous speed of the contact X, the process then being advanced to a step 55 to memorize the value B of Tv if the speed is lower than the synchronous speed of the contact X. At this moment, the user can move the objective zoom 13 to shift its focal length in a direction that is opposite to the direction of the zoom lens's intended adjustment during the mid-exposure mode The mode select switch Pz 33 can then be manipulated to

to be set in Exz mode. It is judged, in a step 56, whether or not the wide-angle switch 29 is

  The process proceeds to a step 57 if the wide-angle switch 29 is set to ON to drive the zoom motor 4 to return the process to step 53. The process proceeds to step 58 if the grand switch is turned on. angle 29 is not

set to ON.

  It is judged in step 58 whether or not the TV switch 30 is set to ON if so the process proceeds to step 57. If it is not so, the

process proceeds to a step 59.

  At step 59, a focal length f1 is stored and it is judged whether or not the trigger switch 31 is turned ON at a step 532. As a result, the process proceeds to step 510 if the switch is set to ON. , and that if it is not

  thus the process is returned to step 56.

  It is judged in step 510 whether or not the wide-angle switch 29 is set to ON and if so the process skips to a step 512 if the switch 29 is set to ON, or the process proceeds to an ON position. step

  If the switch is not turned ON.

  It is judged at step 511 whether or not the TV switch 30 is set to ON, and if so the process proceeds to step 512 or the process returns to

  step 532 if the switch is not turned ON.

  In step 512, the direction of adjustment of the zoom lens is stored, then at a step 513 the zoom engine

  is pressed to advance the process to a step 514.

  In step 514, the counting means 14 initializes its counting operation of the value Td (value counted from the initialization of the adjustment operation of the zoom lens) to advance the process to a

step 515.

  It is judged in step 515 whether or not the value Td is equal to the value A (preset value used to initiate the exposure operation to a selected down counting value after the initialization of the adjustment operation is completed. zoom lens), and the process advances to a step 516 if a preset value is reached or returns to step 514 if the value

  prepositioned is not reached.

  In step 516, a trigger signal is emitted by the exposure start means 9 and it is judged whether the switch 2 CSW (which is intended to be set to ON at the end of the movement of the second

  the focal plane shutter) is ON or OFF.

  As a result, the process proceeds to a step 518 if the switch is set to ON, in order to stop the zoom motor 4, then the process goes back (on the flowchart). If the switch is not placed on

  ON, step 517 is repeated.

  In step 54, the process proceeds to a step 520 if the wide-angle switch 29 is set to ON to drive the zoom motor 4 or the advance process to a

  step 521 if the switch 29 is not turned ON.

  It is judged in step 521 whether or not the TV switch is ON: if it is not, the process proceeds to a step 522, and if it is, the process

advance to step 520.

  It is judged in step 522 whether or not the trip switch is set to ON, and if not so the process returns to step 54. If the switch is set to ON, the process proceeds to a step 523 for operating the exposure start means 9 to output a trigger signal which allows the

  process to advance to a step 524.

  It is judged in step 524 whether or not switch 2 C is ON; if it is not so the process is repeated, and if so the process is going

to BACK.

  In a second embodiment of the present invention, a process immediately following step 514, Fig. 11, is modified; this will be described with reference to Fig. 12 In the first embodiment, after the zoom lens setting operation has been initiated by setting the trigger switch 31 to ON, the value Td is counted to determine the exposure start timing The exposure operation is initiated in this second embodiment by detecting a time at which the f value of the variation

  of the focal length reaches a pre-established value.

  At a step 526, the focal length is monitored after the operation of the zoom motor 4 (step 513). It is judged at a step 527 if A f = A, and the process returns to step 526 if the relation to f = A is not present and the process proceeds to step 528 if A f = A is satisfied to operate the start-up means

  9 to produce the trigger signal.

  It is further judged whether or not the switch 2 CSW is ON (step 529). If the switch is ON, the process is repeated at step 529 and the process quenches the zoom motor 4 (step 530). ) for

go to BACK.

  The adjustment operation of the zoom lens at mid-exposure can thus be performed automatically, simply by setting the start switch 31 to ON, without the proper performance of this operation being based on the technical skill of the user.

  according to the first and second embodiments.

  An exposure operation may further be started within a predetermined period of time after the start of the zoom lens adjustment operation, and it follows that the exposure operation can be started after the setting operation of the zoom lens becomes stable, which eliminates the inconvenience of the type of camera shake and unstable speed of zoom lens adjustment The disadvantage of the excessive clarity of the image of the object photographed before the beginning of the adjustment operation of the zoom lens is thus eliminated. The control circuit of the camera 10 will be described hereinafter in accordance with the third embodiment of the invention with reference to Fig. 13. The components which are similar to those present in the first and second embodiments will be indicated by numerical references

  similar to those used for this embodiment.

  The control section 1 comprises a shutter speed memory means 50 and a zoom function completion means 24 in addition to the various means described in connection with the second and third embodiments, a selector or switch

  rotary shutter 51 being connected thereto.

  The function of the shutter memory means 50 is to store the shutter speed as set by the rotary shutter switch. The completion means of the zoom function 24 acts to stop the zoom motor 4 when the shutter speed counting by the counting means 14 reaches a predetermined level in relation to the shutter speed as stored by the

  shutter speed memory means 50.

  The third embodiment is similar to the first embodiment with respect to many aspects of operation but has a number of differences in the process subsequent to step 516,

  fig 11 This process appears in fig 14.

  At step 514, the counting means 14 initiates the

counting of the value Td.

  It is judged, at a step 515, whether the value Td is equal to the value A; if it is not so, the process is repeated and if so is the process

advance to step 516.

  In step 516, the trigger signal is generated by the exposure start means 9 for

  advance the process to a step 549.

  In step 549, the counting means 14 counts the exposure time after the start-up means

  Exhibition 9 has initiated its exhibition operation.

  In step 550, the shutter speed memory means 50 compares a value that has been calculated to be 80% of the shutter speed stored by the shutter speed memory means 50 at the shutter speed. As a result, if the exposure time T is shorter than the calculated value, the process is repeated at step 549 and if the exposure time T is longer than the calculated value or is equal to this one, the process advances to a

step 551.

  In step 551, the zoom motor 4 is stopped in accordance with a signal delivered by the zoom function completion means 24 and the process proceeds to a step 559 after the end of the adjustment operation of the zooming operation. zoom lens. It is judged at step 559 whether or not switch 2 CSW is ON If this is not so, the process repeats step 559 and if so, the

process goes back.

  The adjustment operation of the zoom lens at mid-exposure can thus be performed automatically without its correct execution being based on the technical skill of the user. The operation of adjusting the zoom lens can also be completed automatically. before the end of the exhibition operation In this way, anyone who wishes can easily use the technique of photographing the object immediately at the end of the exhibition.

  the adjustment operation of the zoom lens.

  In the above embodiment, the shutter speed memory means 50 compares the exposure time T with a value set to correspond to% of the shutter speed as stored by the speed memory means. shutter 50; such a percentage of the value calculated with respect to the speed

  shutter can be set up as desired.

  The control circuit of the camera 10 will be described in accordance with the fourth embodiment of the invention, with reference to Fig. 15. The parts common to the fourth and third embodiments are designated by reference numerals.

similar digital

  The control section 1 comprises a coding plate brush 28 intended to come into contact with a coding plate 22, a memory switch 32, a trip switch 31, these components being all interconnected on the input side, in addition to various

  switches and means according to the description which has

  has been given for the third embodiment The control section 1 further comprises length memory means 45, exposure control means 46, motor speed control means

  47 and focal length detector means 49.

  The focal length memory means 45 has the function of storing the focal length fi when a zoom lens setting operation terminates at a position where the zoom lens setting operation is to be stopped and stored. the focal length f 2 at the position in which the adjustment operation is initiated

of the zoom lens.

  The exposure control means 46 controls the exposure in response to the signals delivered by the means

  shutter speed memory 50.

  The motor speed control means 47 calculates an appropriate rotation speed of the zoom motor 4 in response to the shutter speed Tv which is inputted by means of shutter speed memory 50 to control the zoom motor. 4 so that the zoom motor can be rotated

at the calculated speed.

  The focal length detector means 49 receives signals as stored by the decoder 67 via an objective CPU 66 which enables it to detect the focal length at the time of the adjustment operation of

the zoom lens.

  The starting means of the zoom lens setting operation 8, in the same embodiment, operates the zoom motor 4 to output control signals via the motor speed control means 47 in response to the signals. input from the wide-angle switch 29 or the television switch 30, which allows

  initiate the adjustment operation of the zoom lens.

  The present embodiment has many aspects that are identical to those described for the first embodiment, except for a process that must be executed after step 59. This difference

is shown in Figs. 16-18.

  The control sequences that are the same as those described for the first embodiment are executed until step 58. If the tele switch 30 is not turned ON at this step, the process

advance to step 594.

  The memory switch 32 is set to ON to store the focal length f1 when the adjustment operation of the zoom lens is completed by the zoom lens adjustment operation and its composition is determined in the step It is then judged whether or not the memory switch 32 is turned ON at step 594. If it is not so, the process is repeated and if so, the process proceeds to step 569. In step 569, the focal length fi for stopping the zoom lens adjustment operation is stored in the focal length memory means 45 to judge whether the wide-angle switch 29 is or not placed on

ON (step 570).

  If the latter switch is set to ON, the process proceeds to a step 572 to drive the zoom motor 4 thus initiating the adjustment operation of the zoom lens.

  not set to ON, the process proceeds to step 571.

  It is judged at step 571 whether the telly switch 30 is set to ON or not, and if so the process proceeds to step 572 to drive the zoom motor 4 thereby initiating the setting operation of the zoom lens The process advances to a step 573 if the

  switch is not set to ON.

  The memory switch 32 is set to ON so that the memory means 45 can memorize the focal length at the moment of initiation while the composition of an image is determined by the zoom operation. It is then judged at step 573 if the memory switch 32 is ON or OFF If it is not ON step 570 is repeated, while the process proceeds to

  step 574 if the switch is ON.

  In step 574, the zoom lens adjustment lens 13 has its stored position in the focal length memory means 45 in the form of a focal length f 2 upon initiation of the image adjustment operation.

  zoom lens and process advances to step 575.

  In step 575, the focal length of completion of the zoom lens adjustment operation as stored in step 569 and step 513 is compared to the focal length of the start time of the zoom lens. zoom lens adjustment operation f 2 As a result, the process is repeated, if a relation: fl = f 2 exists and the process proceeds to a step 576 if a relation: fl = f 2

is not established.

  At step 576, the zoom motor 4 is rotated to drive the zoom objective lens 573 into a focal length of completion of the zoom lens adjustment operation to move forward. at

a step 577.

  In step 577, the motor speed control means 47 calculates an appropriate rotation speed of the zoom motor 4. This appropriate rotation speed is calculated as follows: It is assumed that the focal length at the completion of the adjustment operation of the zoom lens is established as fi lmml and the focal length at the start of the zoom lens setting operation is f 2 lmml, the value of the variation A f lmml being then be obtained from the following equation: A f = f 2-fl If the shutter speed is t lsecl and if the variation value of the focal length per revolution of the zoom motor 4 is A f (1), then the zoom motor 4 is rotated to the value of: A f / A f (1) The rotation speed of the zoom motor 4 to accomplish this rotation is therefore t sec, and the following relation exists: (A f / A f (1)) / t = (f 2-fl) / A f (1) t the number of revolutions / secl The mode switch 33 is then actuated

  to switch the operating mode to Exz mode.

  It is judged at a step 578 whether or not the trip switch 31 is turned ON and if the switch is not ON the process is repeated, and the process proceeds to a step 579 if the switch

is set to ON.

  It is determined at step 579 whether or not the trip switch is ON and the trip switch is not turned ON, the process is repeated at step 578, and the start means of exposure 9 are actuated to produce the trigger signal if the switch is placed on

ON (step 586).

  At step 587, it is judged whether: l f> 0, and the process proceeds to step 584 if not

not so.

  If A f> O is not true, the process proceeds to step 589 to drive the zoom motor 4 to a

wide angle adjustment side.

  The process proceeds to step 588 if: A f <O to drive the zoom motor 4 to the TV side. At a step 590, the focal length is monitored to judge whether or not the focal length f 2 for initiation of the zoom lens adjustment operation is equal to the focal length f chosen as the target. As a result, the process is repeated at step 587 if: f f 2, and the process proceeds to step 591 if: f = f 2 to stop the zoom motor 4 using the means

  completion of the zoom function 24.

  It is judged at a step 592 whether or not the switch 2 C is set to ON; the process is repeated at step 592 if the switch is not turned ON and the process goes to BACK if the switch is set to

MARKET.

  The adjustment operation of the zoom lens at mid-exposure can therefore be performed automatically without its good performance being based on the technical skill of the user and the speed of adjustment of the zoom lens can be established as it is appropriate from the results of the comparison between the focal length and the shutter speed. This is how the blur of an image to be photographed in the mid-exposure zoom lens adjustment mode can be rendered

  uniform and free of any irregularity of density.

  In Fig. 19, the control circuit of the camera 10 which includes the zooming function of the mid-exposure zoom lens will be described hereinafter with reference to the fifth embodiment of the invention. omitted with respect to parts that are identical to those in the fourth mode

of realization.

  The control section 1 further comprises a comparison means 53. This comparison means 53 has the function of comparing a variation of the focal length as detected by the focal length variation detection means 49 'with a factor of variation of

  focal length C that has been pre-established.

  The focal length variation detecting means 49 'has the function of detecting a variation of the focal length at the time of the zoom lens adjustment operation in response to the codes which are read by the encoder brushes 28 from The motor speed control means 47 controls the rotational speed of the zoom lens adjustment motor 4 in order to make constant a change in the focal length at the time of the adjustment operation of the zoom lens. the zoom lens. The operation of this embodiment will be

  described below with reference to FIGS. 20 to 22.

  When the trip switch 15 is half-depressed to set the SWS light measurement switch to ON at step 596, it is judged whether the mid-exposure zoom lens setting operation should be not performed at a step 597 The process proceeds to a step 598 if the mid-exposure zoom lens adjustment operation is to be performed, and advances to step 54 if the zoom lens adjustment operation mid-exposure is not expected (Fig 10) The process that must be performed after this step 54 is

  the same as that shown in fig 10.

  The rotary shutter switch 51 is then actuated to preposition a speed

appropriate sealing.

  It is judged at step 598 if the value Tv (shutter speed) is less than the speed

  Synchronous contact X (synchronous flash speed).

  As a result, the process is repeated at step 597 if the shutter speed is not slower than the synchronous contact speed X, and the process advances to a step 5100 if this speed is slower than the synchronous contact speed X. In step 5100, the value B of Tv as prepositioned by means of the shutter selector is recorded in the speed memory means

  shutter 50 to advance the process to a step 5101.

  It is judged at step 5101 whether or not the wide-angle switch 29 is set to ON; the process proceeds to a step 5102 if the switch is set to ON to drive the zoom motor 4 to return it to step 598. If the wide-angle switch 29 is not turned ON, the process proceeds to a further step. step 5103. It is judged at step 5103 whether or not the telly switch is ON and the process proceeds to step 5102 if the telly switch is turned ON, and the switch advances to a step 5104 if the

  switch is not set to ON.

  In step 5104, a focal length f1 for completion of the zoom lens adjustment operation is stored in the memory means 45 to advance.

the process at a step 5105.

  It is judged in step 5105 whether the trip switch 31 is ON or OFF. the process returns to step 5100 if the trip switch 31 is not set to ON and advance to a step 5106 if

  the switch is set to ON.

  It is judged at step 5106 whether or not the wide-angle switch 29 is set to ON; the process jumps to a step 5109 if the switch is set to ON and the process proceeds to a step 5108 if the

  switch is not set to ON.

  It is judged at step 5108 whether or not the TV switch is ON; the process is repeated at step 5105 if the switch is not turned ON and the process proceeds to step 5109 if the switch is set to ON to repeat its sense memory

of the zoom lens setting.

  At a step 5110, the zoom motor 4 is actuated by the starting means of the zoom lens setting operation 8 and the trigger switch is operated by the exposure start means 9 at a step 5111 so that to produce trigger signals to arrive at the next step a

step 5112.

  In step 5112, a variation in the focal length as stored by the focal length variation detecting means 49 'is monitored to memorize the focal length f 2 for starting the zoom lens adjustment operation. then the process

is advanced to a step 5113.

  In step 5113, a variation f in the focal length is calculated and the process is advanced to a step 5114. In step 5114, the counting means 14 is actuated to count down the time t, which makes it possible to

  calculate A f / A t (variation over time).

In a step 5121, the comparing means 53 compares A f / A t as calculated in step 5114 to a variation factor C of the focal length as preset. As a result, the process proceeds to step 5122 if: A f / A t> C, which makes it possible to reduce the rotation speed of the zoom motor 4 by means of the speed control means

the engine 47.

  In turn, the process advances to a step 5123 if: A f AT <C, which makes it possible to increase the rotation speed of the zoom motor 4 by means of the speed control means

the engine 47.

  When equality is reached, the process proceeds to step 5124 where it is judged whether or not switch 2 CSW is ON. The process returns to step 5112 if the switch is not turned ON and advanced. at a step 5125 to stop the zoom motor 4

  and goes to BACK if the switch is set to ON.

  The embodiment therefore allows the user to conveniently perform the mid-exposure zoom lens adjustment operation thereby enabling him to control the rotation speed of the zoom motor 4 in the appropriate manner in relation to with a focal length variation factor as preset This arrangement may allow the user to maintain a focal length variation factor at a constant value at the time of the zoom lens adjustment operation, thereby providing to the user the opportunity to

  make an image that has a uniform image blur.

  The sixth embodiment of the control circuit for the camera 10 will be described hereinafter with reference to Fig. 23 The control section 1 is different in this embodiment of the control section 1 described in the fourth mode. embodiment and shown in Fig 15 in that are provided 54 means for limiting the start of the zoom These limitation means 54 serve to actuate the adjustment operation of the zoom lens at mid-exposure only when the speed of shutter is less than the synchronous contact speed X as stored by the means of

  shutter speed memory 50.

  The means for terminating the zoom function 24 and the motor speed control means 47 perform the following functions. The means for terminating the zoom function 24 stops the driving of the zoom motor 4 by emitting a signal of Zoom lens adjustment completion The motor speed control means 47 operates to stop the zoom lens adjustment operation when the powered zoom lens 13 reaches a focal length of completion of the adjustment operation. of the zoom lens fi as stored in the focal length memory means 45 when adjusting the zoom lens at mid-exposure, thereby completing the setting operation of

the zoom lens.

  The operation of this embodiment will be

  described below with reference to FIGS. 24 and 25.

  At a step 5130, when a user half depresses the trigger switch to set the SWS light measurement switch to ON, this action allows the user to judge whether the zoom lens adjustment operation is halfway -exposure must be performed at step 5131 If the mid-exposure zoom lens adjustment operation is provided, the process proceeds to a step 5132 The process proceeds to step54 if the adjustment operation of zoom lens to

  mid-exposure is not planned (fig 10).

  In step 5132, the start limiting means of the zoom lens adjustment operation 54 is used to judge whether the value T v as prepositioned by means of the rotary shutter switch 51 is slower than the synchronous speed. As a result, when the shutter speed is greater than the synchronous contact speed X, the process returns to step 5131 and is then advanced again to step 54, while the process advances to a step 5133 if the shutter speed is lower than the synchronous contact speed X. In step 5133, the value B of Tv as preset by the rotary shutter switch 51 is stored by the speed memory means

  shutter 50 to advance the process to a step 5134.

  It is judged at step 5134 whether or not the wide-angle switch 29 is set to ON. If this switch is set to ON, then the process proceeds to a step 5135 to drive the zoom motor 4 to derive the process to step 5132 The process is then advanced to a step 5136 if the wide-angle switch

29 is not set to ON.

  It is judged at step 5136 whether or not the TV switch is ON. As a result, the process proceeds to step 5135 if the TV switch is turned ON and the process proceeds to step 5138.

  if the TV switch 30 is set to OFF.

  It is judged at a step-IF 38 if the memory switch 32 is set to ON or not. The process is repeated from step 5134 if the switch is not turned ON and the process advances to a step 5139 if the switch is set to ON By releasing memory switch 32 while it is pressed for the zoom lens adjustment operation, the focal length is stored in this position, which allows the user to memorize the focal length fi for the completion of the zoom lens adjustment operation

(step 5139).

  At a step 5140, the operation of storing the focal length f 2 for the start of the operation of

  Zoom lens adjustment is performed.

  It is judged at a step 5141 if the wide-angle switch 29 is set to ON or not. The process proceeds to a step 5142 if the switch is set to ON, while the process proceeds to a step 5143 if

  the switch is not set to ON.

  At step 5142, the lens is set to a wide-angle position by the focal length of f, advancing

  thus the process up to a step 5145.

  It is judged at step 5143 whether or not the TV switch is set to ON. The process proceeds to step 5144 if the switch is set to ON and

  returns to step 5141 if it is not so.

  At step 5144, the lens is set to move to a tele position by the focal length of

  f, advancing the process to step 5145.

  It is judged at step 5145 whether the trip switch 31 is set to ON or not. The process proceeds to a step 5146 if the switch is turned ON and the process is repeated at step 5145 if the

  switch is not set to ON.

  Operation of the zoom motor 4 is then started (step 5146) to cause the exposure start means 9 to set the trip switch to ON, thereby actuating the switch to produce the trigger for the initiation of the exposure. exhibition operation

(step 5147).

  At a step 5154, the focal length as stored by the focal length detector means 49

  is monitored to advance the process to a step 5155.

  It is judged at step 5155 if: f = fl, i.e. if the focal length fa reaches the focal length fi for the completion of the zoom lens adjustment operation If the result n is not equality, the operation returns to step 5154 and the process is advanced to a step 5156 if the result is equality. In step 5156, the motor speed control means 47 stops the operation of the zoom motor 4

  to thus advance the process to a step 5157.

  It is judged at step 5157 whether or not switch 2 CSW is ON. The process proceeds to step 5158 if the switch is turned ON and the process is repeated at step 5157 if the switch is not ON.

not set to ON.

  In step 5158, the exposure is terminated and a number of data such as the focal length fi for completion of the zoom lens setting operation and the like are erased to leave the process

go to BACK.

  The embodiment thus allows the user to automatically perform the adjustment operation of the zoom lens at half exposure conveniently without the proper execution of this operation is based on the technical skill of the user. zoom motor 4 being rendered inactive when the motor speed control means 47 has reached the focal length fi as memorized for the completion of the operation of the zoom lens adjustment during the zoom lens adjustment to With the exposure, the user can stop the zoom lens adjustment operation at any given time to a focal length of completion of the zoom lens adjustment operation fi which has been preset by viewing a zoom lens. object through the viewfinder to verify its position The user can thus save himself the inconvenience of a only partial completion of the operation of adjusting the zoom lens at the moment when the exposure operation becomes t ermine and an incomplete realization of the desired photographic effect despite the execution of the adjustment operation of the zoom lens at mid-exposure The user can, in this way, imagine the finished photograph of a object before she

actually taken.

  It is, moreover, also possible to design the embodiment so that the focal length f 2, for the initiation of the zoom lens adjustment operation, can be varied according to the value. Tv When presetting the focal length f 1 for completion of the zoom lens adjustment, it may also be possible to arrange the embodiment so that a warning signal can be emitted in the where the focal length would not be achieved during the overall exposure time as a function of the shutter speed as

than pre-established at this time.

  The seventh embodiment of the present invention will now be described hereinafter. The control circuit of this embodiment is identical to that of the sixth embodiment of FIG. 23 except for the functions of the completion means of the present invention. zoom function 24 and

  motor speed control means 47.

  In other words, the function of completing the zoom function 24 in this embodiment is to stop the zoom motor 4 when the counting means 14 reaches a preset level in relation to a shutter speed as stored by the shutter speed memory means 50 The motor speed control means is operable to control the zoom motor 4 so that an appropriate rotational speed of the zoom motor 4 can be calculated according to of the focal length of completion of adjustment of the zoom lens f 1, of the focal length from the setting of the zoom lens f 2, each of which has been stored in the focal length memory means 45 and with a shutter speed Tv which has been inputted by means of shutter speed memory. The motor is further controlled to turn

the speed thus calculated.

  The operation of the camera in accordance with this seventh embodiment of the

  The present invention is illustrated in FIGS. 26 to 28.

  At a step 5161, the trip switch is half-depressed to set the SWS light measurement switch to ON, to allow the user to judge whether the mid-exposure zoom lens adjustment operation must be used If the user decides to perform the adjustment operation of the zoom lens at mid-exposure, the process is advanced to a step 5163 and the process proceeds to a step 5164 if the adjustment operation of the zoom lens at mid-exposure

is not planned.

  It is judged in step 5164 whether or not the wide-angle switch 29 is set to ON. The process proceeds to a step 5179 if the switch is set to ON thereby causing the zoom motor 4. The process proceeds to a step 5180 if the switch is not placed

ON.

  It is judged in step 5180 whether or not the telly switch is ON If the switch is turned ON, the process proceeds to step 5179 to drive the zoom motor 4 and the process proceeds to a step 5181 if the TV switch 30 is not placed on

MARKET.

  It is judged at step 5181 whether or not the shutter release switch 15 is set to ON and the process is repeated if the switch is not turned ON. The process is advanced at a step 5182

  if the switch is set to ON.

  In step 5182, a trigger signal is emitted by the exposure start means 9 to advance

the process at a step 5183.

  It is judged at step 5183 whether or not the switch 2 C is turned ON and the process is repeated if the switch is not set to ON. The process is

  advanced to a step 5184 to go back.

  In step 5163, a means for limiting the start of the adjustment operation of the zoom lens 54 acts to judge whether the value Tv as prepositioned by the selector 51 is lower than the synchronous contact speed X It results that the process returns to step 5162 to advance to step 5164 if the shutter speed is lower than the synchronous contact speed X Therefore, if a pre-set shutter speed is faster than the synchronous contact velocity X, simultaneous operation of the wide-angle switch 29 and the trip switch 15 will never occur and will not occur either between

  TV switch 30 and the trip switch 15.

  This serves to avoid slit exposure in which an accented slot illuminated by the flash light is formed on an image and causes an irregularity of the image density that would otherwise be due to the operation.

  adjusting the zoom lens at mid-exposure.

  In a step 5165, the value B of Tv as prepositioned by means of the rotary shutter switch 51 is stored by the speed memorizing means

  shutter 50 to advance the process to a step 5166.

  It is judged in step 5166 if the wide-angle switch 29 is turned ON or not and the process proceeds to a step 5167 if the switch is turned ON to drive the zoom motor 4 to jump to the step 5163 The process proceeds to a step 5168 if the

  wide-angle switch 29 is not set to ON.

  It is judged at step 5168 whether or not the TV switch is ON and the process is advanced at step 5167 if the TV switch 30 is set to ON. The process is advanced at step 5169 if the

  TV switch 30 is not set to ON.

  It is judged at step 5169 whether memory switch 32 is set to ON or not. The process is repeated at step 5166 if the switch is not turned ON while the process is advanced at step 5170 if the switch is set to ON A triggering of the memory switch 32 in the zoom lens setting mode by the user allows a storage of the

focal length in this position.

  With this procedure, the user is able to read the focal length of completion of the adjustment operation of the zoom lens f 1 at step 5170. At a step 5171, the focal length f 2 for the initiation of the zoom lens adjustment operation

is memorized.

  It is judged at a step 5172 if the wide-angle switch 29 is set to ON or not. The process proceeds to a step 5173 if the switch is set to ON. If the switch is not turned ON, the switch is set to ON.

  process is advanced to a step 5174.

  In step 5173, the lens is caused to move to the wide angle position by the value of a focal length equivalent to the value of A f, and the process then advances to a step 5176.

  is obtained as described below.

  Assuming that the focal length at the time of completion of Exz (zoom exposure) is f 1 lmml, the value of Tv is B lsecl, the rate at which the focal length is caused to vary is Vf and a constant K is set, being chosen to stop the zoom lens adjustment operation when 80 t of the overall exposure time period is exceeded in relation to the shutter speed, it follows that: A f = Vf x K x B = 0.8 Vf B It is then judged at step 5174 whether or not the TV switch 30 is set to ON. The process is advanced to a step 5175 if the switch is turned ON and returns to step 5172 if not

not so.

  At step 5175, the lens is zoomed to the TV side by the focal length value

equivalent to the value of A f.

  It is judged at step 5176 whether or not the trip switch 31 is set to ON. The process is advanced at a step 5177 if the switch is turned ON and the process is repeated at step 5176 if the

  switch is not set to ON.

  In step 5177, actuation of the zoom motor

4 is started.

  At a step 5178, the exposure start means 9 sets the trigger switch to ON to output trigger signals, allowing

  the user to trigger the exposure operation.

  At a step 5185, a focal length that has been stored by the focal length detector means 49 is monitored and the process is advanced to a step 5186. It is judged at step 5186 if a relation such that: f 2 = f 1 + A f is verified The process returns to step 5185 if the equation above is not verified and is then advanced

  at a step 5187 if the equation above is verified.

  At step 5187, the zoom motor drive

  4 is stopped to advance the process to a step 5188.

  It is judged at step 5188 whether or not switch 2C is set to ON. The process proceeds to step 5189 if the switch is turned ON and the process is repeated if the switch is not set to ON.

MARKET.

  In step 5189, the exposure operation is performed and the value Tv and the focal length f 1 as well as A f that have been inputted are, in addition,

  cleared to let the process go to BACK.

  In this embodiment, the adjustment operation of the mid-exposure zoom lens can be carried out automatically and conveniently without its good execution being based on the technical skill of the user, and all the more so as the zoom lens setting starting medium 54 limits the operation of the mid-exposure zoom lens adjustment operation when the shutter speed is greater than a pre-set reference shutter speed (synchronous speed of contact X) and can reliably avoid the occurrence of slit exposure with the inconveniences that would result from performing the mid-exposure zoom lens setting operation with a slit exposure regime,

  especially the irregularities in the density of the image.

  The eighth embodiment of the invention will now be described below. The relation between the focal length f and the aperture value of the diaphragm F is shown in FIG. 33. This relation between the focal length f and the number F is maintained in proportion. Thus, since the number F is varied in response to the focal length f, an exposure value to be imposed on a film surface varies with the value F, thereby causing uneven exposure. realization allows the user to automatically and conveniently perform the operation of adjusting the zoom lens to mid-exposure and thus eliminate, this time again, the occurrence of a

such irregularity of exposure.

  In Fig. 29, the arrangement of the electric zoom lens is identical to that shown in Fig. 4 The relationship between the F-value and the focal length f for the powered zoom lens is the same as that shown in FIG.

  fig 33 in the full range of the zoom setting.

  Signals that are stored via a decoder 67 are delivered to an objective CPU 66. The objective CPU 66 determines the focal length f and its corresponding value F based on the output delivered by the decoder. 67 These data are output to the body control section 84

of camera 80 -

  The control circuit 84 is usually composed of microcomputers whose function is to drive the zoom motor 4 for a zoom operation in accordance with the program that has been stored in the memory.

Internal ROM.

  A portion of the luminous flux from the object to be photographed after passing through the lens groups L1 and L2 is transmitted through a half-mirror section of the main mirror 81 and is reflected by the lower mirror 82 for insertion into the mirror. CCD distance measuring detector 83 This distance measuring detector 83 is of the phase difference detecting type and supplies to a control section 84 the image phase information which has been divided in two. The control section 80 performs a pre-interpolation calculation in accordance with the phase difference information to obtain a defocus value, thereby enabling the user to perform such focusing

  mechanical arrangement is known per se.

  The camera body 80 includes the SWS light measuring switch, a mirror 81, the shutter release switch 15 which serves to initiate the exposure operation by controlling the shutter as well as the aperture (not shown) and the mode select switch 16 which is used to select the half-exposure zoom lens adjustment mode, all these components being connected to the input port of the zoom section.

order 84.

  The embodiment includes the mode select switch 16 which is used to select the mid-exposure zoom lens adjustment mode. This mid-exposure zoom lens setting mode being selected, the wide exposure switch angle 29 or the TV switch 30 is operated to select either the TV zoom mode or the TV zoom lens adjustment mode or the zoom lens adjustment mode

wide-angle, respectively.

  As a variant, the adjustment of the wide-angle zoom lens can be chosen when the powered zoom lens 13 is in the TV position and the adjustment operation of the telephoto zoom lens can be carried out when the zoom lens is located. in the wide-angle position, the lens being able to be adjusted in the opposite direction when the focal length at the time of initiation of the exposure operation is in a wide-angle position,

in a TV position.

  When the motorized zoom lens 13 is set from the focal length fo to the focal length f n, the aperture value F is caused to vary from the value F o to the value F n as shown in Fig. 33 In the eighth embodiment, the adjustment speed of the zoom lens is increased to the wide-angle position when the iris value F is low (large aperture of the iris) and the zoom speed of the zoom lens is reduced to the TV side when the value large diaphragm F (small diaphragm aperture) This speed variation is used to keep the intensity of the incident beam constant, that is, the exposure value on the film surface in the entire ranges of the film.

adjusting the zoom lens.

  This variation in the speed of adjustment of the zoom lens can be achieved by varying the rotational speed of the zoom motor 4 or by varying the profile of the cam paths 72, 73 in the cam ring 19 while maintaining constant rotation speed

the zoom engine 4.

  The adjustment of the motor speed can be achieved by varying the pulse frequency in the case where the zoom motor 4 is constituted by a pulse motor or by varying the voltage in the case where the zoom motor 4 In either case, the rotational speed for each of the focal lengths f can be determined from the equation: R = g (F) Ro o Ro is a rotational speed in position

wide-angle and g (F) = 1/20011092.

  This relationship is represented in the graph of

fig 30.

  In order to keep the rotation speed of the zoom motor 4 constant, the speed of the zoom lens adjustment is made variable by varying the profiles of the cam paths 72 and 73 In this case, the range of gradations of the focal length can be expressed by the equations: H = h (f) Ho, where Ho is a range of gradations around the grandangle position, and h (f) = 2 "o = o = o Fo) nog 2 this relation being

  represented by the graph of Figure 31.

  An example of distance scaling, this condition being given, is shown in FIG. 32 The ranges of graduations of distance t 1 to t 4 as represented in FIG. 32 can be obtained from the following equation: fth (f Fig. 34 shows a distance scale in which a focal length is maintained at a constant level with respect to the rotation angle of the ring.

zoom control 13.

  This embodiment therefore allows the user to automatically and conveniently perform the adjustment operation of the zoom lens at mid-exposure without the proper execution of this operation is based on his technical skill and the user can avoid the exposure irregularity by exposing an image which may vary with the zoom adjustment operation at a constant intensity despite changes in the F-number of full aperture or a preset F-value as a function of the zoom adjustment operation In addition, the speed of the zoom adjustment can vary in a motorized zoom lens according to the change in the value of the number F. The user is therefore able to expose the image with a constant light intensity regardless of the focal length and thus photograph an image with a blur that is free from any irregularity of

  density whatever the conditions.

Claims (15)

  A camera (10) having a magnifying zoom function characterized by comprising: a zoom motor (4) for driving a zoom lens (13); a trigger switch (31) which serves to trigger a mid-exposure zoom lens setting; means for performing the zoom lens adjustment operation which serves to drive the drive away from said zoom lens; zooming motor (4) on the basis of actuation of said start switch (31) for start an exhibition.   A camera (10) according to claim 1, characterized in that said magnifying lens zoom setting means includes means for triggering the zoom lens setting operation (9) which serves initiating driving of said zoom motor (4) based on actuation of said trigger switch (31), exposure starting means for triggering exposure based on operation of said triggering the adjustment operation of the zoom lens and means for detecting a condition sufficient to validate the exposure starting means (9) to trigger an exposure in synchronism with the operation of the start means of the setting operation of the zoom lens.   A camera (10) according to claim 2, characterized in that said means for detecting sufficient conditions comprises a half-exposure zoom function which is used to count the time in synchronism with the start means of the operation of adjusting the zoom lens until conditions, sufficient to validate the exposure start-up means used to trigger an exposure, have identified.   A camera (10) according to claim 3, characterized in that said means for detecting sufficient conditions comprises a means for counting (14).   A camera (10) according to claim 2, characterized in that said means for detecting sufficient conditions monitors a variation of the focal length in synchronism with the actuation of the starting means of the adjustment operation of the camera. zoom lens (8) and identifies a sufficient focal length (f) as constituting the condition   enough to start an exposure.   A camera (10) according to claim 2, characterized in that said camera further comprises a start switch (31) by which the starting means of   the adjustment operation of the zoom lens (8) is operated.   A camera (10) according to claim 3, characterized in that said time counted by the mid-exposure zoom function is the period during which the zoom lens's zoom speed becomes constant. The camera (10) according to claim 3, characterized in that said predetermined time is set to 1/10 of the overall exposure time. A camera (10) according to claim 1, characterized in that said means for performing the mid-exposure zoom lens setting operation comprises means for starting the lens adjustment operation zoom lens (8) for starting the driving of said zoom motor (4) based on the operation of said trigger switch, an exposure start means (9) for launching an exposure based on the actuating said zoom lens setting operation starting means, counting means (14) for counting the exposure time in synchronism with the operation of said start means of the setting operation of the zoom lens; the zoom lens (8), means for storing a preset shutter speed and means for completing the zoom lens setting operation (24) which serves to stop the driving of said zoom lens; zoom (4) when the value counted by said average in counting (14) reaches the predetermined rate of the overall exposure time corresponding to the shutter speed stored by said means of   shutter speed memory (50).   A camera (10) according to claim 9, characterized in that said means for storing a preset shutter speed further comprises a rotary shutter switch (50) operable to set a shutter speed to be stored in memory in the means for memorizing a   preset shutter speed.   The camera (10) according to claim 9, characterized in that said predetermined rate of overall exposure time is 80% of the time global exposure.   A camera (10) according to claim 1, characterized in that said means for performing the mid-exposure zoom lens setting operation comprises means for starting the lens adjustment operation zoom lens (8) which serves to drive the driving of said zoom motor (4) on the basis of one actuation of said trigger switch, an exposure start means (9) which serves to output an exposure on the based on the operation of said zoom lens setting operation starting means, a focal length detecting means (49) for detecting the focal length of said zoom lens (13), a memory means of a focal length (15) for storing a focal length at the beginning of the zoom lens adjustment operation and a focal length at the completion of the zoom lens adjustment operation, a means which serves to memorize a preset shutter speed and shutter speed control means (47) for controlling the driving speed of said zoom motor based on the focal length data stored by said focal length memory means and a speed data of shutter stored by said   shutter speed memory means (50).   The camera (10) according to claim 12, characterized in that said camera further comprises a memory switch (32) and that said focal length memory means (45) operate based on the operation said memory switch.   A camera (10) according to claim 12, characterized in that said means for storing a preset shutter speed further comprises a rotary shutter switch (50) operable to set a shutter speed which must be memorized by the means used to memorize   a preset shutter speed.   A camera (10) according to claim 1, characterized in that said means for executing the mid-exposure zoom lens setting operation comprises means for starting the zoom lens adjustment operation Apparatus (8) for starting the driving of said zoom motor (4) on the basis of operation of said trigger switch, exposure start means (9) for launching an exposure on the basis of the actuating said zoom lens adjusting operation starting means, zooming length detecting means (45) for detecting the amount of variation of the focal length at which said zoom lens (13) has been subjected to a comparison means (53) for comparing a focal length variation detected by said focal length variation detecting means with a predetermined focal length rate of change and a velocity control means of the controller (47) for controlling the rotational speed of said zoom motor (4) on the basis of the result of the comparison by said comparison means (53) so as to maintain the focal length rate of change when operation of adjusting the zoom lens to a constant value.   A camera (10) according to claim 15, characterized in that said motor speed control means (47) increases the rotation of the zoom motor (4) when the focal length variation detected by the variation detection means of focal length (49 ') is greater than the predetermined focal length variation rate and that said motor speed control means (47) decreases the rotation speed of the zoom motor when the focal length variation detected by the means for detecting a change in focal length (49 ') is less than the rate of variation   predetermined length of the focal length (f).   Photographic apparatus (10) according to claim 1, characterized in that said means for starting the zoom lens adjustment at the exposure comprises means for starting the zoom lens adjustment operation (8) which is used to initiating driving of said zoom motor based on actuation of said trigger switch, exposure starting means (9) for outputting an exposure on the basis of actuation of said starting means zoom lens setting operation (8), memory means (32) for storing the focal length (f) upon completion of the zoom lens setting operation, and a means motor control device for stopping said zoom motor when the focal length reaches said focal length upon completion of the zoom lens setting operation as stored in said focal length memory means (45) during the reg operation zoom lens at mid-exposure. A camera (10) according to claim 17, characterized in that said zoom lens (13) comprises a memory switch (32) and that said focal length memory means for storing the focal length (f) when of the completion of the zoom lens adjustment operation works on the   base of one actuation of said memory switch.   A camera (10) according to claim 1, characterized in that said means for performing the zooming operation of the mid-exposure zoom lens comprises means for starting the zoom lens adjustment operation (8) which serves to drive the driving of said zoom motor (4) on the basis of the actuation of said trigger switch, an exposure start means (9) which serves to start an exposure on the basis of actuating said zoom setting start means, means for storing a preset shutter speed and start limiting means of the zoom lens setting operation (54) which serves to allow the zoom lens operation of said mid-exposure zoom lens setting operation means only when the shutter speed stored in the means for storing a preset shutter speed is less than a speed of o predetermined standard build. A camera (10) according to claim 19, characterized in that said predetermined standard shutter speed is a synchronous contact speed X. A camera (10) according to claim 1, characterized by further comprising a Mid-exposure zoom lens adjustment mode for performing a zoom lens adjustment operation during exposure and control means for varying the speed of the lens adjustment operation zoom during an exposure according to the variation of the diaphragm due to the adjustment operation of the zoom lens.   Camera (10) according to claim 21, characterized in that the zooming speed of the zoom lens is set to increase when the aperture is set for a clear day and   slow down when set for a cloudy day.