JP3683630B2 - camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate operation for switching a photographing mode in accordance with the attachment/detachment of an externally mounted stroboscope. SOLUTION: This camera incorporates a Hall IC 40 detecting the magnetic field of a magnet provided in the externally mounted stroboscopic unit by attaching the stroboscopic unit to the camera. The IC 40 incorporates a Hall sensor and a comparator and performs switching action according to whether the magnitude of the magnetic field is larger or smaller than a specified value. By turning on the IC 40, an external stroboscope attaching signal inputted in a control part 27 is switched from a high level to a low level. The control part 27 switches the photographing mode to an externally mounted stroboscope mode interlocked with switching the level of the signal.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a camera to which an external strobe is detachably mounted, and more particularly to control of a camera that switches a shooting mode in accordance with detachment.
[0002]
[Prior art]
Conventionally, some cameras are equipped with an external strobe to perform strobe photography. The external strobe has a built-in power supply battery, strobe light emission circuit, strobe charging circuit, etc., and uses a direct connection contact of the accessory shoe of the camera in conjunction with turning on the power switch provided outside. Send and receive signals to and from. Signal exchange includes a charging completion signal sent from an external strobe and a sync signal sent from a camera.
[0003]
In such a camera, the camera photographing mode is switched to the external strobe mode by turning on the power switch after attaching the external strobe. In this mode, for example, shooting is performed with auto strobe control that stops the strobe emission when the shutter is fixed at the strobe synchronization speed when the aperture is opened, and the strobe light reflected from the subject is appropriately measured by TTL direct measurement.
[0004]
[Problems to be solved by the invention]
However, in the above-described camera, if an operation for turning on the power switch of the external strobe is forgotten, the photographing mode is not switched, and the strobe photographing cannot be performed, resulting in a failed photograph. Further, in such a camera, shooting is performed by operating the shutter button, regardless of whether or not the strobe side charging completion signal is output because of the concept of giving priority to photo opportunity. Therefore, if the shutter release is performed when the flash charging is not completed, the flash emission is not performed with a sufficient amount of light, which may result in a failure photo.
[0005]
The present invention has been made in order to eliminate the above-described problems, and is designed to simplify the operation of switching the shooting mode according to the attachment and detachment of the external strobe, and to prevent shooting when charging is not completed. The purpose is to provide a camera made.
[0006]
[Means for Solving the Problems]
  In order to solve the above problems, the camera of the present invention measures the subject distance between the closest position and infinity in response to the half-pressing operation of the shutter button, and focuses the photographing lens on the subject. Auto focus controlAn autofocus control means for performing; and switching to the autofocus control means in the normal mode,Manual focus control that varies the focus of the photographic lens according to the operation of an external focus ringManual focus control means for performing;An external strobe attachment detecting means for detecting attachment of a close-up strobe attached to the outside and sending out a attachment signal; for outputting the attachment signal;responsedo itSaidControl means for switching from the normal mode to the external strobe mode, wherein the control means sets the focus of the photographing lens to the closest position in conjunction with the transition to the external strobe mode, and then the autofocus. The control is stopped and switched to the manual focus control. According to this, just by attaching the close-up strobe to the camera, the external strobe attachment detecting means detects the close-up strobe being attached and sends a mounting signal, and the control means switches the camera shooting mode to the external strobe mode. It is simple.
[0007]
  Also, contactIn the case of shooting using a copying strobe, as is well known, shooting can be performed by changing the shooting magnification using a close-up lens. When the close-up strobe is attached to the camera, it is expected that the photographing magnification will be changed by attaching the close-up lens, so the control means switches the focus mode to manual. Thus, the photographer manually focuses before photographing. Since the operation at this time is of course close-up photography, the distance to the subject is short, and the photographing lens is operated to focus on the subject distance at the closest position in order to photograph at the maximum photographing magnification. However, if the photographic lens is infinitely focused at the time of mode switching, for example, if the operation is to focus by rotating the focus ring, the focus ring need not be rotated many times. It will be hard work. Therefore, in order to make this operation simple and quick, the control means is the closest closest subject distance among the subject distances in which the photographing lens of the camera is focused by autofocus control in conjunction with switching to the external strobe mode. After performing control to focus on the position, switch to manual.
[0008]
  Further, a communication means for transmitting / receiving a signal to / from the close-up flash with the close-up flash installed, and a frontWhile the output of the mounting signal is not obtained,Built-inUpon receiving a charging completion signal obtained from the strobe, a strobe shooting standby signal is sent, and while the mounting signal output is obtained, the communication meansFor close-upA strobe charging completion signal switching means for sending out the strobe shooting standby signal when receiving a charging completion signal sent from the strobe, and displaying the strobe charging completion on the display unit by receiving the strobe shooting standby signal, Control means that does not allow shooting until a flash shooting standby signal is receivedAnd may be provided.According to this, the strobe charging completion signal switching meansBuilt-inWith strobeFor close-upThe charging completion signal obtained from the strobe is switched and received in conjunction with the output of the wearing signal, the strobe shooting standby signal is sent to the control means in response to this reception, and shooting is not allowed until the control means receives this signal Because of this control, you can shoot with a sufficient amount of light.
[0009]
  The configuration of the external strobe attachment detection means isAttaching an external strobe with a magnetic sensor that detects the magnetic field of the magnet provided on the attached strobeMay be.A Hall sensor, Hall IC, or magnetoresistive element can be used as the magnetic sensor. However, the Hall sensor and the comparator are built in and the switching operation is performed when the magnitude of the magnetic field is larger or smaller than the specified value. A type of Hall IC is preferable because of its high reliability.Furthermore, the control means of the present invention may illuminate the subject by intermittently emitting the close-up flash for a predetermined time in response to a half-pressing operation of the shutter button in the external flash mode.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
A camera 10 shown in FIG. 1 is an autofocus single-lens reflex type instant camera. The camera 10 has a built-in strobe device (hereinafter referred to as “internal strobe”), and emits strobe light from the light emitting window 11 exposed to the outside toward the subject during strobe photography. When performing close-up photography, the close-up flash device 12 can be attached as an external flash. The close-up flash device 12 includes a flash holder 13, a mount adapter 14, a close-up lens 15, an external flash unit 16, and the like.
[0011]
The strobe holder 13 is attached to the camera 10. On the other hand, the mount adapter 14 and the close-up lens 15 are attached to the external strobe unit 16 and can be handled integrally. The photographer can shoot by selectively selecting the normal mode and the external strobe mode by inserting / removing the external strobe unit 16 to / from the strobe holder 13. The normal mode includes an auto strobe mode using an internal strobe and a strobeless mode not using this.
[0012]
As is well known, the camera 10 is in shooting standby by turning on the power switch 17. Specifically, as shown in FIG. 2, in the photographing standby state, the subject light incident on the photographing lens 18 is guided to the optical path of the finder unit 19, and the photometric window 21 is operated by half-pressing the shutter button 20. And the distance measuring window 22 to measure and measure the distance, move the focus lens group 18a forward and backward in the direction of the optical axis 18b according to the subject distance obtained by the distance measurement, and press the shutter button 20 fully. The opening / closing of the shutter 25 is controlled according to the photometry by the operation, and the subject light is guided to the internal exposure frame 24 by the movement of the mirror mechanism 23 provided between the photographing lens 18 and the optical path of the finder unit 19 for exposure. .
[0013]
  As a result of the photometry, if the subject brightness is below a predetermined level, the internal strobe is activated. In this operation, strobe light is emitted toward the subject by a sync signal obtained from the shutter 25, and the light reflected by the subject is received by a light receiving sensor built in the back of the opening 26 on the front surface of the camera so that an appropriate exposure is obtained. Auto strobe control that stops the strobe light halfway. The state of charge of the internal strobe is displayed on the inside of the finder 19 at the same time as the charging is completed, and can be confirmed while looking through the finder 19. These are all controlled by the control unit 27 in a centralized manner. In the autofocus control, for example, the photographing lens 18 can be focused on a subject distance from 0.3 m (closest position) to infinity.As described above, the means for performing the autofocus control for measuring the subject distance between the closest position and infinity and focusing the photographing lens 18 on the subject in response to the half-pressing operation of the shutter button of the present invention. Auto-focus control means is configured.
[0014]
  In the external strobe mode, for example, the shutter speed is 1/60, the exposure is fixed at full aperture, and the focus mode is switched to manual focus. Manual focus operation is based on the subject image viewed from the viewfinder 19InThe focus ring 28 exposed outside the lens barrel of the camera 10 is rotated so as to be in focus. At this time, when switching to the external strobe mode, the position at which the photographic lens 18 is focused on the closest position among the focusing positions in the autofocus control so that the rotation operation of the focus ring 28 can be reduced. Driven by.The means for performing manual focus control for changing the focus of the taking lens 18 in accordance with the operation of the focus ring 28 provided outside constitutes the manual focus control means of the present invention.
[0015]
The uppermost film unit 31 stacked in the film pack 30 is located in the exposure frame 24, and after the exposure is completed, the film unit 31 is scraped out by a scraping claw. The developer unit pod of the film unit 31 thus scraped off is cleaved by a pair of developing rollers 32, and the developing solution contained in the developer pod is spread, and then passes through the discharge port 33 to the outside of the camera 10. Discharged. At this point, the film unit 31 has completed the necessary processing, and a printed photograph can be obtained after a predetermined time has elapsed.
[0016]
On the bottom surface of the camera 10, when the external strobe unit 16 is mounted, a communication circuit 35 for communicating a control signal with the external flash unit 16 is incorporated. The communication circuit 35 includes a signal transmission / reception unit 36 and an external strobe attachment detection unit 37, which are comprehensively controlled by the control unit 27. The signal transmission / reception means includes a transmission means, a reception means, a reception control means, and a strobe charge completion signal switching means. The transmission means transmits a half-press signal, a full-press signal, and a sync signal to the external strobe unit 16. The receiving means receives a charge completion signal sent from the external strobe unit 16. The external strobe attachment detection means 37 sends an external strobe attachment signal to the control unit 27 by detecting the attachment of the external strobe unit 16.
[0017]
The reception control means operates the receiving means when the external strobe attachment detection means 37 detects the attachment of the external strobe unit 16, and the external strobe attachment detection means 37 does not detect the attachment of the external strobe unit 16. The operation of the receiving means is stopped.
[0018]
The strobe charging completion signal switching means sends a strobe shooting standby signal for notifying strobe shooting standby to the control section 27 by receiving a charging completion signal obtained from the internal strobe while the external strobe mounting detecting means 37 does not detect the mounting. In addition, while the external strobe attachment detection unit 37 detects the attachment, the strobe photographing standby signal is sent to the control unit 27 when the receiving unit receives the charging completion signal of the external strobe unit 16. Regardless of the internal or external strobe, the control unit 27 turns on the LED inside the finder 19 by receiving a strobe shooting standby signal, and notifies the photographer of the completion of charging. 2 is a communication window incorporating a visible light cut filter that cuts visible light and transmits only infrared light.
[0019]
One embodiment of such a camera communication circuit 35 is shown in FIG. The external strobe attachment detection means 37 is composed of, for example, a Hall IC 40, a switching transistor 41, a voltage dividing circuit 42, and an A / D circuit 43. The Hall IC 40 incorporates a Hall sensor and a comparator, and performs an operation of turning on the switch when the magnitude of the magnetic field is larger than a specified value, and turning off the switch when the magnetic field is small.
[0020]
The switching transistor 41 and the voltage dividing circuit 42 switch the level of the output signal sent to the A / D circuit 43 to high or low in conjunction with the switching operation of the Hall IC 40. The A / D circuit 43 switches the output voltage to the “H” or “L” signal depending on whether the input voltage is at a high level or a low level with respect to the specified value, and sends the output voltage to the control unit 27 as an external strobe attachment signal. Thereby, the control unit 27 can recognize whether or not the external strobe is mounted by switching the input voltage of the external strobe mounting signal from “H” to “L” or from “L” to “H”. In conjunction with, the shooting mode is switched from the normal mode to the external flash mode.
[0021]
The receiving means is a phototransistor 44, which receives an optical signal indicating completion of charging from the external strobe unit 16. The strobe charge completion signal switching means is composed of five switching transistors 45, 46, 47, 48, and 50.
[0022]
The switching transistor 46 is turned on when the switch of the Hall IC 40 is turned on, supplies power to the phototransistor 44 to enable the switching operation of the switching transistor 45, and is turned off when the switch of the Hall IC 40 is turned off. Then, the power supply to the phototransistor 44 is stopped, and the switching operation of the switching transistor 45 is deactivated. The switching transistor 45 is turned on when the switching transistor 46 is turned on and an optical signal is input to the phototransistor 44, and sends a strobe shooting standby signal indicating completion of standby of the external strobe to the control unit 27. The strobe shooting standby signal is softly applied by the control unit 27 to the “H” level voltage. When the switching transistor 45 is turned on, this voltage drops to the “L” level. Recognizes that a standby signal has been input.
[0023]
A charge completion signal sent from the internal strobe circuit 49 is input to the base of the switching transistor 50. The transistor 50 is turned on when a charge completion signal is received. The switching transistor 47 is turned on when the switching transistor 46 is turned on. That is, the switching transistor 47 ignores the internal strobe charge completion signal when turned on, and monitors the internal strobe charge completion signal when turned off. The switching transistor 48 is turned on when the switching transistor 47 is turned off and the switching transistor 50 is turned on, and sends a strobe photographing standby signal indicating that charging of the internal strobe is completed to the control unit 27. Note that the strobe shooting standby signal is used for both the internal strobe and the external strobe.
[0024]
As a result, when the external strobe unit 16 is attached, the charge completion signal sent from the internal strobe circuit 49 is ignored, and the control unit 27 is connected to the strobe in synchronization with the reception of the external strobe charge completion signal from the phototransistor 44. A shooting standby signal is sent. When the external strobe unit 16 is disconnected, a strobe shooting standby signal is sent to the control unit 27 in synchronization with the input of a charging completion signal for the internal strobe at the switching transistor 50. The control unit 27 receives the strobe shooting standby signal and displays an LED display indicating that the strobe shooting using the internal strobe or the external strobe shooting is possible.
[0025]
The transmission means gives a control signal to the external strobe unit 16 as an optical signal, and is composed of three infrared LEDs 51, 52, and 53. The infrared LED 51 is lit when the switch 20a for detecting the half-pressing operation of the shutter button 20 is turned on, and the infrared LED 52 is lit when the switch 20b for detecting the full-pressing operation of the shutter button 20 is turned on. To do. Further, the infrared LED 53 is turned on by a sync signal output from the internal strobe circuit 49 in conjunction with the opening / closing of the shutter 25. As shown in the figure, the control unit 27 applies an “H” level voltage in software to the infrared LEDs 51 and 52, respectively. When the switch 20a or the switch 20b is turned on, the voltage becomes “ It is recognized that a half-press signal or a full-press signal has been input by detecting a drop to the “L” level.
[0026]
FIG. 4 is a display unit 54 provided outside the camera 10 and shows a fully lit state. In the normal mode, the control unit 27 shoots based on the setting of manual or autofocus, light / dark control, self-timer, daytime flash photography, or flash prohibition photography according to the operation of the switches 55, 56, 57, and 58. The mode is executed, and these settings are notified to the outside by displaying a mark or a character segment corresponding to the setting on the liquid crystal display unit 54.
[0027]
In the external strobe mode, the control unit 27 performs control to display this on the external display means. This display is as shown in FIG. In this display, that is, in the external strobe mode, the control unit 27 invalidates the setting changes of the other switches 55, 56, 58 except the self-timer setting switch 57.
[0028]
The strobe holder 13 of the close-up strobe device 12 is a part in which the front frame portion 60 and the holding portion 61 are integrally connected, and is attached to the camera 10 as described above. The front frame 60 is formed with an opening 62 that exposes the photographing lens 18 of the camera 10, the distance measuring window 22, the photometric window 21, and the like, and is attached to the front surface of the camera 10 with a mounting screw 63. The holding unit 61 is for holding the strobe unit 16, and is attached to a tripod seat on the bottom surface of the camera 10 with a mounting screw 64.
[0029]
The holding portion 61 has a U-shaped cross section in which the rectangular upper surface extending in the direction of the optical axis 18b is opened, and the front surface is also opened for mounting the strobe unit 16. Protrusions 65 and locking holes 66 are respectively provided inside the character shape. The protrusion 65 turns on a switch 79 for a strobe charging circuit, which will be described in detail later, when the strobe unit 16 is mounted. The locking hole 66 is engaged with a locking claw 75 of a locking mechanism, which will be described in detail later, so that the locking hole 66 is not easily detached when the strobe unit 16 is mounted.
[0030]
A plurality of close-up lenses 15 are prepared. When used in combination with the photographing lens 18, the close-up lens 15 can focus on the shortest subject distance up to, for example, 8.2 cm (shooting magnification 1.6 times). As shown in FIG. 6, screw portions 67 and 68 having the same filter diameter are formed on the outer periphery of the rear end and the inner periphery of the front end, respectively. The threaded portion 67 on the outer periphery of the rear end is a male screw, and is used when screwed into the mount adapter 14 and attached, and is used when another close-up lens is used in an overlapping manner. The screw portion 68 on the inner periphery of the front end is a female screw and is screwed into a male screw of another close-up lens.
[0031]
The mount adapter 14 serves to attach the close-up lens 15 to the strobe unit 16, and has a female screw portion 69 for screwing and attaching the close-up lens to the rear end of the inner periphery. Three claws 70 for bayonet coupling are formed. The three claws 70 have an inner diameter larger than that of the close-up lens 15 so that a plurality of close-up lenses 15 can be attached. The close-up lens 15 attached to the screw portion 69 is correctly determined at a position close to the photographing lens 18 when attached to the camera 10.
[0032]
The strobe unit 16 includes a front part 71 and a mounting part 72. A large circular opening 73 is formed in the front surface portion 71 so as to surround the optical axis 18b. The opening 73 serves as a photographing window that exposes the photographing lens 18 of the camera 10. On the back side of the front portion 71, a three-claw receiver 74 that is connected to the three claws 70 of the mount adapter 14 by a spring yacht is provided so as to surround the opening 73.
[0033]
The attachment portion 72 is attached to the holding portion 61 of the strobe holder 13 by being inserted from the front side along the direction of the optical axis 18b. A locking claw 75 that constitutes a locking mechanism is exposed to the outside of the mounting portion 72. When the mounting portion 72 is mounted on the holding portion 61, it naturally engages with the locking hole 66. The lock mechanism is unlocked by depressing a lock release button 76 that is exposed outside the mounting portion 72.
[0034]
A ring-shaped light emitting portion 77 is provided on the front surface of the front surface portion 71 so as to surround the opening 73, and a ring-shaped discharge tube 78 is built in the back of the light emitting portion 77. The light emitting unit 77 has a function of a diffusion plate that diffuses the light emitted from the discharge tube 78 and makes it uniform toward the subject. The discharge tube 78 is not limited to a single ring-shaped discharge tube, and may be configured by arranging a plurality of discharge tubes in a ring shape. Moreover, it is good also as a structure which has arrange | positioned the discharge tube of 2 lamps on either side on both sides of the optical axis 18b.
[0035]
The mounting portion 72 is provided with a power switch 79 and a magnet 80 exposed to the outside, and a circuit portion 81 including a power battery is built in the mounting portion 72. The power switch 79 is a push-type switch that is turned on only while the switch piece 79a is being pushed in, and is disposed in a state where the switch piece 79a protrudes outside the back surface.
[0036]
Specifically, as shown in FIG. 7, the circuit unit 81 includes a strobe circuit 82 and a communication circuit 83. The strobe circuit 82 includes a control circuit 84, a strobe charging circuit 85, a strobe light emitting circuit 86, and a dimming control circuit 87. A communication circuit 83 for performing optical communication with the camera 10 includes an infrared LED 88 and three phototransistors 89 to 91, which are connected to a control circuit 84, respectively.
[0037]
The strobe charging circuit 85 charges the main capacitor with a high voltage obtained by boosting the voltage of the power supply battery 94, and monitors this charging state. When the charging state of the main capacitor becomes less than the specified voltage, the charging is performed again. When the voltage is charged, a charge completion signal is sent to the control circuit 84. The strobe light emission circuit 86 has an intermittent illumination function that illuminates the subject by intermittently discharging the discharge tube 78 and a strobe main light emission function that stops the intermittent discharge and synchronizes with the synchro signal to discharge the discharge tube 78. When the operation of the strobe main light emission function ends, a strobe completion signal is sent to the control circuit 84.
[0038]
The control circuit 84 is connected to the communication circuit 83, the power switch 79, the shade control switch 84a, and the illumination selection switch 84b. When the power switch 79 is turned on, the control circuit 84 is obtained from the shade control switch 84a and the illumination selection switch 84b. The strobe charging circuit 85 and the strobe light emitting circuit 86 are controlled based on the received signal. When the power switch 79 is turned on, the control circuit 84 operates the strobe charging circuit 85 to start charging, and supplies power to the phototransistors 89 to 91 so that they can be received. By receiving a charging completion signal from the strobe charging circuit 85, the infrared LED 88 of the communication circuit 83 is turned on. When an optical signal that is a half-press signal from the camera 10 is obtained from the phototransistor 89, the control circuit 84 activates the intermittent discharge function of the strobe light emitting circuit 86, and intermittently when an optical signal that is a full-press signal is obtained from the phototransistor 90. Stop the discharge function. When an optical signal that is a sync signal is obtained from the phototransistor 91, the strobe light emission function of the strobe light emission circuit 86 is activated.
[0039]
The density control switch 84a and the illumination selection switch 84b are provided on the back side of the front portion 71 so as to be operable from the outside. The control circuit 84 of the external strobe unit 16 adjusts the amount of strobe light in 2/3 EV steps within a range of ± 4/3 EV by operating the density control switch 84a, and half-presses the shutter button 20 by operating the illumination selection switch 84b. Controls whether or not the intermittent discharge function is performed during operation.
[0040]
The control circuit 84 is provided with a timer circuit 80c. The timer circuit 80c is activated after the switch 79 is turned on. For example, when a half-press signal or a strobe completion signal cannot be obtained within 5 minutes. Automatically stops the operation of the strobe charging circuit 85 and prevents the power supply battery 94 from being consumed.
[0041]
The dimming control circuit 87 receives the light reflected from the subject during the main flash emission by the dimming sensor 92 provided on the inner surface of the opening 73 of the front surface 71, and the discharge lamp 78 of the discharge tube 78 so as to achieve proper exposure. Control to stop discharging halfway. Reference numeral 93 denotes a communication window incorporating a visible light cut filter that cuts visible light and transmits only infrared light. Further, the power supply battery 94 built in the mounting portion 72 can be replaced with a new battery by opening a lid provided on the bottom surface of the mounting portion 72.
[0042]
  Next, the operation of the above configuration will be described. When the power switch 17 of the camera 10 is turned on without the external strobe unit 16 being attached, the switch of the Hall IC 40 is turned off as shown in FIG.6Accordingly, the switching transistor 41 is also turned OFF, and an “H” level external strobe non-mounting signal is input to the control unit 27 through the voltage dividing circuit 42. Thereby, the control unit 27 selects the shooting mode as the normal mode. Further, since the switching transistor 46 is OFF, the phototransistor 44 is inactivated. Further, since the switching transistor 47 is OFF, the charging signal of the internal strobe is monitored.
[0043]
In such a state, for example, even if disturbance light is input to the phototransistor 44, the switching transistor 45 does not turn on, and therefore it is possible to prevent malfunction of the control unit 27.
[0044]
When close-up flash photography is performed with the camera 10, the flash holder 13 is attached to the camera 10 as shown in FIG. This attachment is strong because the two attachment screws 63 and 64 are used in two directions perpendicular to the camera 10. With this attachment, the front frame portion 60 is disposed on the front surface of the camera 10, the holding portion 61 is disposed on the bottom surface of the camera 10, and the opening 62 is formed in the front frame portion 60. Shooting is possible.
[0045]
On the other hand, the mount adapter 14 and the close-up lens 15 are attached to and integrated with the external strobe unit 16. The integrated external strobe unit 16 is attached to the strobe holder 13. For this mounting, the mounting portion 72 is inserted into the holding portion 61 along the direction of the optical axis 18b. As a result, the locking claw 75 is locked in the locking hole 66, and the external strobe unit 16 and the strobe holder 13 are mounted in the state shown in FIG. In this state, the photographing lens 18 and the close-up lens 15 are maintained at a predetermined distance.
[0046]
When the external strobe unit 16 is attached to the strobe holder 13, the magnet 80 is provided in the Hall IC 40, the infrared LED 88 is provided in the phototransistor 44, the phototransistor 89 is provided in the infrared LED51, the phototransistor 90 is provided in the infrared LED52, and The phototransistor 91 comes close to and faces the infrared LED 53 across the communication windows 38 and 93, and the protrusion 65 pushes the switch piece 79a.
[0047]
When the magnetic field of the magnet 80 is detected, the Hall IC 40 turns on the switching transistor 41 via the switching transistor 46. When the transistor 41 is turned on, the high-level external strobe attachment signal input to the control unit 27 is switched to the “L” level. Thereby, the control unit 27 on the camera 10 side switches the photographing mode from the normal mode to the external strobe mode.
[0048]
When the shooting mode is switched to the external strobe mode, the control unit 27 drives the shooting lens 18 to a position where the subject distance at the closest position is in focus, and then switches the focus mode to manual and controls the display unit 54. A display to this effect is shown in FIG.
[0049]
Further, since the switching transistor 46 is turned on in response to the mounting signal from the Hall IC 40, power is supplied to the phototransistor 44, and the switching operation of the switching transistor 45 is allowed. Further, since the switching transistor 47 is turned on, the switching transistor 48 is deactivated regardless of the presence or absence of the charging completion signal of the internal strobe, and the charging signal of the external strobe is monitored.
[0050]
On the external strobe unit 16 side, the control circuit 84 causes the strobe charging circuit 85 to start charging by turning on the charging start switch 79. When charging is completed, the strobe charging circuit 85 sends a charging completion signal to the control circuit 84. When receiving the charge completion signal, the control circuit 84 causes the infrared LED 88 to emit light for a predetermined time.
[0051]
This optical signal is input to the phototransistor 44 of the camera 10. When the phototransistor 44 receives the optical signal, the switching transistor 45 is turned on, so that a strobe shooting standby signal for external strobe is sent to the control unit 27. By receiving the strobe shooting standby signal, the control unit 27 turns on the LED inside the finder 19 in the same way as the internal strobe charging completion display, and allows the execution of the external strobe mode sequence.
[0052]
The photographer fixes the prepared camera 10 on a tripod or the like, looks through the viewfinder 19 and presses the shutter button 20 halfway. With this half-press, the switch 20a is turned ON, and a half-press signal is sent from the camera 10 to the strobe unit 16. When the control circuit 84 of the external strobe unit 16 receives this signal by the phototransistor 89, it controls the strobe light emitting circuit 86 to discharge the discharge tube 78 intermittently. This intermittent discharge is automatically stopped in 5 seconds, for example. The object image illuminated during this time is looked through the finder unit 19, and the focus ring 28 is rotated so that the object image is in focus, thereby focusing. This operation is in a state in which the photographing lens 18 is focused on the subject distance at the closest position, so that it can be focused by a slight operation and can be performed instantaneously. If it is desired to illuminate the subject again, the half-press operation is performed again.
[0053]
When focusing is completed, the shutter button 20 is fully pressed. By this full pressing operation, the switch 20b is turned ON and a full pressing signal is sent to the external strobe unit 16 as an optical signal. Further, when the control unit 27 receives the full press signal, the shutter 25 is operated. At this time, a sync signal synchronized with the full opening of the shutter 25 is output from the internal strobe circuit 49, and the infrared LED 53 emits light.
[0054]
The control circuit 84 of the external strobe unit 16 controls to stop the intermittent discharge of the strobe light emitting circuit 86 when the phototransistor 90 receives the light signal that is the full push signal, and then the photo signal that is the synchro signal is the photo signal. When the light is received by the transistor 91, the strobe light emission circuit 86 is controlled to perform strobe main light emission. By this strobe main light emission, the discharge tube 78 is instantaneously discharged to irradiate the strobe light. The strobe light is reflected by the subject and enters the photographing lens 18 through the close-up lens 15. The discharge of the discharge tube 78 is controlled so that the dimming control circuit 87 stops when the reflected light received by the dimming sensor 92 becomes appropriate.
[0055]
The control unit 27 of the camera 10 operates the shutter 25 after moving the mirror mechanism 23 so that the subject light is guided to the exposure frame 24 when the full-press signal is received. Thus, the subject light transmitted through the photographing lens 18 is guided to the exposure frame 24 and is incident on the uppermost film unit 31 stacked in the film pack 30. The exposed film unit 31 is scraped to a pair of developing rollers 32 by a scraping claw, the developer pod is cleaved by the pair of developing rollers 32, and the developing solution is spread, and then passes through the discharge port 33. It is discharged outside the camera 10.
[0056]
Note that the control unit 27 does not allow the external flash mode sequence when it does not receive a flash shooting standby signal indicating the completion of charging of the external flash, so that it can reliably perform flash shooting with an appropriate amount of light. At this time, since the LED inside the finder 19 is turned off as in the case of the internal flash photography, the photographer is not given a sense of incongruity.
[0057]
When shooting in the normal mode, the lock release button 76 of the flash unit 16 is pressed. As a result, the lock between the mounting portion 72 and the holding portion 61 is released, and thereafter the strobe unit 16 can be easily removed from the strobe holder 13 by pulling the mounting portion 72 along the direction of the optical axis 18b. This is the state shown in FIG. As a result, on the camera 10 side, the detection of the magnetic field of the magnet 80 of the Hall IC 40 is cut off, so that the control unit 27 switches the photographing mode to the normal mode and controls the display unit 54 to display this. The setting operation of the setting switches 55 to 58 is allowed.
[0058]
On the external strobe unit 16 side, the charging start switch 79 is turned off when the external strobe unit 16 is removed, so that charging in the strobe charging circuit 85 is automatically stopped. Thereby, the consumption of the power battery 94 can be prevented.
[0059]
In the above embodiment, the shooting mode is switched in conjunction with the installation of the external strobe unit 16 for close-up photography. However, the present invention is not limited to this. Mode switching may be performed in conjunction with the installation of a large-capacity external strobe that enables shooting of a wide range of strobes, such as in a warehouse with little storage. Further, the external strobe mounting detection means is constituted by the Hall IC 40 and the magnet 80, but the present invention is not limited to this, and instead of the Hall IC 40, a simple magnetic sensor such as a Hall sensor or a magnetoresistive element may be used. Instead of the magnetic sensor, for example, a push-type button switch or the like may be used, but a Hall IC that performs a switch operation is preferable in terms of reliability.
[0060]
【The invention's effect】
  As explained in detail aboveOf the present inventionIn the cameraFor close-upSince it is equipped with external strobe attachment detection means that detects the strobe attachment and sends out the attachment signal, and control means for switching the camera shooting mode to the external strobe mode by receiving the output of the attachment signal. Compared to the type that switches the mode by operating the power switch etc. one by one,For close-upSince the shooting mode is automatically switched just by attaching the strobe to the camera, it is simple in terms of operability.
[0061]
  Also,The control means switches the focus mode to manual in conjunction with switching to the external flash mode, and the camera's taking lensBecause the focus is adjusted to the closest position, Focusing during close-up flash photography is easy, and you can focus instantly.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a close-up flash device and a camera according to the present invention.
FIG. 2 is an explanatory view showing a state in which a strobe holder is attached to a camera.
FIG. 3 is a circuit diagram showing an electrical configuration of a communication circuit of the camera.
FIG. 4 is an explanatory diagram in which the display unit of the camera is fully lit.
FIG. 5 is an explanatory diagram showing a form displayed on the display unit in the external strobe mode.
FIG. 6 is an explanatory view showing a state in which a close-up lens is attached to an external strobe unit.
FIG. 7 is a block diagram showing a strobe circuit and a communication circuit of an external strobe unit.
FIG. 8 is an operation state diagram showing the operation of the communication circuit in conjunction with whether or not the external strobe unit can be attached.
FIG. 9 is an explanatory diagram showing a state in which a strobe unit is attached to a camera.
[Explanation of symbols]
10 Camera
13 Strobe holder
16 Strobe unit
27 Control unit
35 Communication circuit
40 Hall IC
79 Power switch
80 magnets
83 Communication circuit

Claims (2)

A built-in strobe and a close-up strobe that is detachably attached to the outside. A normal mode consisting of an internal strobe mode that uses the built-in strobe or a strobeless mode that does not use the strobe, and an external that uses the strobe In cameras that shoot by switching the shooting mode between strobe mode,
An autofocus control means for performing autofocus control for measuring a subject distance between the closest position and infinity in response to a half-pressing operation of the shutter button and focusing the photographing lens on the subject;
Manual focus control means for performing manual focus control for changing the focus of the photographing lens in accordance with an operation of a focus ring provided outside, which is selectively used with the auto focus control means in the normal mode. ,
An external strobe mounting detection means for detecting the mounting of a close-up strobe that can be detachably attached to the outside and sending a mounting signal;
And a control means for switching to the external flash mode from the normal mode in response to an output of said mounting signal,
The control means sets the photographing lens focus to the closest position in conjunction with the transition to the external strobe mode, and then stops the autofocus control and switches to the manual focus control. camera.   2. The control means illuminates the subject by intermittently emitting the close-up flash for a predetermined time in response to a half-pressing operation of the shutter button in the external flash mode. Camera.

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