JP2003186093A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera capable of reducing the influence of shaking of hands during underwater photography where shaking of hands often occurs since the camera cannot be held well. <P>SOLUTION: In the camera, an underwater detecting part 3 discriminating whether the photographing environment is on land or underwater and CPU 1 determining whether flash light emission in photographing is needed or not based on the brightness of a subject are provided. The discrimination level of brightness of the subject in determination of whether or not the flash light emission is needed is changed over by the CPU 1 according to the photographing environment discriminated by the underwater detecting part 3. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera technology that can be used both in water and on land, and more particularly to a camera having a strobe device capable of dimming for correct exposure even in water.

[0002]

2. Description of the Related Art In recent years, with the spread of outdoor life,
User orientation and demands for underwater photography are increasing, and various proposals have been made regarding waterproof cameras (amphibious cameras) that are cameras that can be used both in water and in the air (land).

Among these proposals, examples of the underwater strobe device include, for example, Jitsukai Sho 60-98.
Japanese Patent No. 836 describes a waterproof connection technology for a strobe device and a camera body underwater, and Japanese Utility Model Publication No. 3-31721 has an underwater detection sensor and determines whether the camera is underwater or not. A technique for changing the control of is described.

That is, according to Japanese Utility Model Laid-Open No. 60-98836, the strobe device and the camera body are connected by an aerial pipe waterproofed by an elastic material so that the strobe device can be connected between a storage position and a projecting position. There is described a waterproof camera that is movable between the two and has a groove or a protrusion for draining water on one or both of the contact surfaces of the strobe device and the strobe device housing portion of the camera body.

According to the above-mentioned Japanese Utility Model Laid-Open No. 3-31721, a camera provided with a water detection sensor and provided with a lens lock means for locking the advance / retreat of the lens when the water detection sensor detects water around the camera. Is described.

[0006]

However, the above-mentioned Japanese Utility Model Laid-Open No. 60-98836 and Japanese Utility Model Laid-Open No. 3172/1993.
None of the conventional techniques including Japanese Patent Publication 1 discloses a specific method for reducing the influence of camera shake in underwater photography in which camera holding is poor and camera shake is likely to occur.

The present invention has been made by paying attention to such a problem, and an object thereof is to reduce the influence of camera shake in underwater photography where camera holding is poor and camera shake easily occurs. To provide a camera.

[0008]

In order to achieve the above object, a first aspect of the present invention relates to a judging means for judging whether the photographing environment is land or underwater, and photographing based on the brightness of the subject. And a determination unit for determining whether or not strobe light emission is to be performed, and the determination unit switches the brightness determination level of the subject in the determination as to whether or not strobe light emission is to be performed in accordance with the shooting environment determined by the determination unit.

According to a second aspect of the present invention, in the camera according to the first aspect, the determination means switches the brightness determination level of the subject in a direction that facilitates stroboscopic light emission when an underwater determination is made.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a view showing the arrangement of a camera according to the first embodiment of the present invention.

In FIG. 1, a CPU (Central Processing), which is an arithmetic control circuit composed of a one-chip microcomputer, etc.
Unit: CPU) 1 is connected to a distance measuring unit 2 that measures the distance to the subject and an underwater detection unit 3 that detects whether the environment in which the camera is used is underwater or in the air (land). In addition, the CPU 1 controls the exposure of the camera by a strobe unit 4 for illuminating the CPU 1 to assist the exposure when a proper exposure is not obtained within a predetermined exposure time under low brightness, and a shutter or the like. The exposure control unit 5 is connected.

In the camera configured as described above,
The CPU 1 controls the strobe unit 4 and the exposure control unit 5 based on the output results from the distance measuring unit 2 and the underwater detection unit 3.

FIG. 2 is a diagram showing the absorption characteristics of light in seawater.

As shown in the figure, in water, light is absorbed by the absorption function α having wavelength dependence, and light is attenuated.

That is, when stroboscopic photography is performed in water, stroboscopic light is absorbed unlike in air. Therefore, even if the amount of light is sufficient to illuminate the subject in the air with a proper amount of light, it is not possible to illuminate the same subject at the same distance with an appropriate amount of light in water.

Therefore, in the first embodiment, with the configuration shown in FIG. 1, the underwater detection unit 3 detects whether or not the environment in which the camera is used is underwater, and based on the result, the strobe unit 4 is detected.
The dimming control means is switched.

Here, in air, generally, if the distance to the subject (subject distance) is L and the aperture of the camera at the time of shooting is FNo, a guide number (hereinafter referred to as GNo) indicating the amount of light emitted by the strobe unit 4 will be described. Note) is appropriate when the relationship of GNo = FNo × L (1) is satisfied. Note that this is the case where the film sensitivity used is ISO100. ISO
(ISO) is the International Standards Organization (Internat)
The ISO 100 is an example of the photographic speed obtained by the sensitometric method defined by ISO.

Therefore, in the case of a camera with a built-in flash, the CP
U1 controls the flash unit 4 so that the light amount GNo of the flash light satisfies the expression (1) according to the subject distance L and the aperture FNo.

The first embodiment is characterized in that dimming is performed in water in consideration of the light absorption coefficient α.

Here, when the amount of light reflected from the subject at the subject distance L is P1 when light is projected on the subject in water with the amount of light P0, this relationship is expressed by the above absorption coefficient α.

[Equation 1] Expressed as

Therefore, in the case of stroboscopic light emission underwater, GNo is calculated from the above equations (1) and (2) in consideration of the forward path at the time of projection and the return path at the time of reflection.

[Equation 2] And need to. In the amphibious camera with a strobe according to the first embodiment, dimming is performed in the air according to the formula (1), and in water, the dimming is performed using the formula (3). At this time, the absorption coefficient α is, for example,
Considering the wavelength of the strobe light, it can be set to approximately 0.1 from FIG.

Many so-called lens shutter cameras have a mechanism in which a diaphragm and a shutter are combined, but in this case, a strobe light of a predetermined GNo is emitted at a timing when the shutter has a predetermined aperture value. The dimming method is known. Even in the lens shutter camera using such a dimming method, dimming can be performed in water using the formula (3).

The dimming in the first embodiment may be a method of controlling the GNo as described above, or may be a method of emitting strobe light of a predetermined GNo at a predetermined FNo. These may be selected depending on the camera configuration.

Next, a camera according to the second embodiment of the present invention will be described.

FIG. 3 is a diagram showing the structure of the camera of the second embodiment.

In the second embodiment, the distance measuring section / underwater detecting section 11
Thus, the distance measuring light is projected onto the subject 12, and the subject distance is detected by the reflected light. A so-called light projection type active autofocus (AF) is applied. In water, infrared light and ultraviolet light have a large absorption coefficient α as shown in FIG. 2. Therefore, in the second embodiment, a xenon discharge tube (hereinafter referred to as Xe tube) 13 having a large visible light component is used as a light source. I am using.

Further, in order to focus and project the distance measuring light in a narrow range, the mask 13 having a fine window in front of the Xe tube 13 is provided.
a and the projection lens 14 are arranged.

Further, the reflected light from the subject 12 is incident on the two semiconductor light position detecting elements (PSD) 16a and 16b through the two light receiving lenses 15a and 15b, respectively.

FIG. 4 is a diagram showing the above-mentioned optical system from light projection to light reception.

According to the principle of triangulation, the incident light positions X1 and X2 become larger as the subject distance L becomes shorter. Here, when the object at the position of the distance L is measured, the distances between the light projecting lens 14 and the light receiving lenses 15a and 15b are S1 and S2, respectively, and the distance between the light receiving lenses 15a and 15b and the PSDs 16a and 16b is fj. Then, the incident light positions X1 and X2 can be expressed by X1 = S1 · fj / L, X2 = S2 · fj / L (4).

Since the light from the Xe tube 13 is emitted during gas discharge, the discharge path changes with each emission, and as shown in FIG. 4, a light beam projected as A is designed. ,
It may tilt like B depending on the conditions at the time of light emission.

However, as shown in FIG.
If the distance measurement calculation is performed by a method of preparing one and adding the incident light positions X1 and X2, it becomes possible to correct the inclination of the light beam when projected as described above. That is, if the distance measurement calculation is performed using the above equation (5) L = (S1 + S2) .fj / (X1 + X2) (5), the errors ΔX1 and ΔX2 shown in FIG. Is A, B
Correct distance measurement is possible regardless of which direction the light is projected.

PSDs 16a and 16b are semiconductor elements that output two current signals depending on the incident light position and the light amount of the incident light. The integrated circuits for autofocus (hereinafter referred to as AFIC) 17a shown in FIG. Reference numeral 17b is an integrated circuit that processes the current signal in an analog manner.

FIG. 5 is a block diagram showing a circuit in the AFIC 17a.

The PSD 16a outputs current signals I1 and I2. These current signals I1 and I2 are PSD1.
Due to the carrier division effect of 6a, the following relationship is satisfied, where X is the incident light position of light.

[0037]

[Equation 3]

The current signals I1 and I2 are amplified β times by the preamplifiers 18 and 19 and the transistors 20 and 21, respectively. In addition, β is the transistor 20, 21
Is the current amplification factor of.

Also, a pair of transistors 22, 23 and 2
With the current mirror circuit consisting of 4 and 25, this β
The currents amplified twice are added together and input to the integration circuit 26 for integration. In this way, the integrating circuit 26 outputs a signal depending on the current signal sum I1 + I2 of the PSD 16a. The current signal sum I1 + I2 is
It depends on the amount of light incident on the PSD 16a.

Further, I1 and I2 amplified in the form of collector currents of the transistors 20 and 21 are compression diodes 2
7 and 28 are input. This compression diode 27, 28
Is input to the respective bases of transistors 32 and 33 configured as a differential type in which a constant current source 31 is connected to a common emitter via buffers 29 and 30.

Here, the current flowing through the constant current source 31 is Iφ.
And the current flowing through the resistor 34 is IOUT, the relationship of IOUT = {I1 / (I1 + I2)} = Iφ (7) holds.

Therefore, the CPU 35 shown in FIG.
If the voltage output generated at both ends of the resistor 34 is read in through an analog / digital (A / D) converter (not shown) built in the CPU 35, the above equations (6) and (7) are used to obtain the light output. The incident light position X can be obtained. From the outputs of the AFICs 17a and 17b having the above functions, C
The PU 35 detects the incident light positions X1 and X2 and the reflected signal light amount.

Therefore, when the incident light positions X1 and X2 are substituted into the above equation (5), S1, S2, and fj are values that have already been determined, so the subject distance L is determined by taking the refractive index of water into consideration. To be The above is the operation of the distance measurement / underwater detection unit 11 and the CPU 35 of the second embodiment.

Next, assuming that the reflected signal light quantity is P, the following relationship is established between P and the object distance L in air when the object has a predetermined reflectance.

[0045]

[Equation 4]

Here, Po is a proportional constant.

On the other hand, in water, considering the attenuation constant α of water, the reflected signal light amount P is

[Equation 5] Becomes The attenuation constant α is a value that changes depending on the salt concentration of water.

In the second embodiment, using the reflected signal light amount P and the subject distance L,

[Equation 6] It is possible to calculate the damping constant α.

Next, the CPU 35 substitutes the calculated damping constant α into the above equation (3) to control the strobe section 36. The flash unit 36 reflects the light from the Xe tube 37 on the umbrella 3.
The Xe tube 37 discharges the electric charge of the capacitor 38 and emits light. This capacitor 38 is for boosting DC via a rectifying diode 39.
It is charged by the / DC converter 40. Also, Xe
A high voltage is applied to the tube 37 by a trigger circuit 41,
By ionizing the inside of the Xe tube 37, the Xe tube 37
Starts emitting light.

A switch 42 is provided in the discharge loop, and the CPU 35 turns on / off the switch 42 to switch the light emission time of the Xe tube 37 of the flash unit 36 to control the light emission amount, that is, GNo.

Similarly, the strobe section 36 for exposure control is used.
The Xe tube 13 for autofocus is also controlled to emit light by the same principle as the light emission of the Xe tube 37, and a capacitor 43 for storing discharge charge, a charging circuit 44 for charging the same, and a rectifying diode 45 are provided. There is. And CP
The U 35 controls the light emission of the Xe tube 13 for autofocus via the trigger circuit 46.

Further, the CPU 35 detects ON / OFF of the release switch 47 linked with the release button of the camera, and further, the brightness of the subject is automatically exposed.
Exposure: AE) Detected via the unit 48.

Further, the aperture value of the taking lens 49 is input to the CPU 35 via the aperture value input section 50 including an encoder and the like, and the CPU 35 controls the shutter 51 and the like on the basis of these pieces of information to take a photographing sequence. To control.

FIG. 6 is an example of an external view of the camera of the second embodiment.

As shown in the figure, the camera body 60 of this camera has a light projecting lens 14 for autofocusing, light receiving lenses 15a and 15b, and Xe which is a stroboscopic light emitting section.
Tube 37, release switch 47 that interlocks with the release button,
A photographing lens 49, a grip portion 61, a window 62 for the AE sensor to detect subject brightness, and a finder objective lens 63 are arranged. Since the objective lens 63 of the finder is used underwater, it has a larger size than that of an ordinary camera.

The camera body 60 is designed to have a waterproof and pressure resistant structure so that it can be used underwater, and the AE section 48 for photometry (not shown) is correct even in underwater of pure blue. It shall have a correction function so that the exposure value can be obtained.

In general, it is apt to be considered that the light for distance measurement of autofocus and the light of strobe do not reach the subject due to the attenuation of the light in water. However, when analyzing underwater photographs, there are many photographs as shown in FIGS. 7 (a) and 7 (b), and in general, a photograph in which the subject exists at a distance of 5 m or more like a group photograph taken on land. Taking into consideration that the transparency of water is not good, etc.
Not probabilistically high.

For example, from the diagram showing the relationship between the wavelength of light and the absorption coefficient shown in FIG. 2, the absorption coefficient α of visible light is 0.
If the value is 1, in the scene as shown in FIG. 7A, when the wide-angle lens is used, the subject distance L is about 1.5 m. Therefore, FNo = 2.8 from the above equation (3), and the GNo at this time is ,

[Equation 7] Becomes Therefore, it can be seen that even a stroboscopic device having a GNo of about 8 mounted on a normal compact camera can sufficiently cope with underwater photography.

FIG. 8 is a flow chart showing the processing of the CPU 35 at the time of photographing by the camera (amphibious camera) of the second embodiment.

In step S1, it is determined whether or not the release button 47 is turned on by pressing the freeze button. When the release switch 47 is turned on, it is determined that the photographing sequence is started, and the process proceeds to step S2.

In step S2, the brightness BV of the subject is obtained using the AE unit 48.

Next, in step S3, the Xe tube 13 for autofocus is caused to emit light, and the outputs from the PSDs 16a and 16b are sent to the CPU 3 via the AFICs 17a and 17b.
5 receives and detects the subject distance L and the reflected signal light amount P by distance measurement. The detection in step S3 has already been described with reference to FIG. 5, and thus description thereof will be omitted.

Next, in steps S4 and S5, the CPU 3
Reference numeral 5 detects whether or not it is underwater using the distance measurement / underwater detection unit 11. In the second embodiment, as shown in FIG. 2, it is determined whether or not it is underwater by utilizing the tendency that the attenuation of light is large underwater. That is, in step S4, the above (1
The light absorption coefficient α is calculated from the equation (0). At this time, α
= 0.01, it is determined to be underwater.

However, depending on the color tone of the subject, α may be about 0.01 even in the air (land). Therefore, if you want to improve the accuracy more,
The mask 13a shown in Fig. 4 is made movable, and light is projected onto a plurality of points on the screen.
It may be determined to be underwater only when == about 0.01.

In addition, when distances can be measured at a plurality of points on the screen in this manner, as another effect, correct focus can be achieved even if a subject exists in a position other than the center of the screen as shown in FIG. 7B. Matching is possible.

In the next step S5, the CPU 35 determines whether or not it is underwater on the basis of the value of the absorption coefficient α in step S4, and if it is determined that it is underwater, step S6.
Then, the GNo is calculated in consideration of the light absorption coefficient α.

On the other hand, if it is determined in step S5 that it is not underwater, the process branches to step S10, and GNo is calculated from the equation (1). However, in the second embodiment, the sensitivity of the film used is assumed to be ISO100 in order to make the description easy to understand. Temporarily, ISO
When using 400 films, GNo may be half of the calculation result by the above formula (1).

Next, in steps S7 and S11, the CPU 35 determines that the brightness BV of the subject is a predetermined value BV.
2, it is determined whether or not less than BV1. When it is smaller, the process branches to step S8, and the above step S3 is performed.
Focusing is performed in accordance with the subject distance L obtained by the distance measurement in.

Then, in step S9, the Xe tube 37 of the flash unit 36 is caused to emit light by the GNo calculated in step S6 or step S10, and the shutter 51 is controlled to perform exposure.

On the other hand, the above steps S7 and S11
When it is determined that the brightness BV of the subject is not smaller than the predetermined values BV2 and BV1, that is, when it is determined that the brightness of the subject is sufficiently bright for shooting, the process branches to step S12, and the above steps are performed. Focusing is performed according to the subject distance L obtained by the distance measurement in S3.

Subsequently, in step S13, the exposure control is performed by opening the shutter 51 for a predetermined time without controlling the strobe section 36.

As described above, in the second embodiment, since the distance measuring unit and the underwater detecting unit are also used as the distance measuring / underwater detecting unit 11, a simple and inexpensive camera can be provided.

The operation of the flash unit 36 is switched depending on the brightness of the subject. Since the judgment levels BV1 and BV2 in judgment steps S7 and S11 are switched between underwater and in the air (on land), the camera shake is set so that the flash fires as much as possible in water where camera holding is poor and camera shake easily occurs. The effect of taking measures can be expected.

Therefore, the above judgment levels BV1 and BV
2, the BV2 is set higher, and the Xe tube 37 of the strobe unit 36 does not need to emit light in the air when the subject brightness is the same as in air and the Xe tube 37 does not emit light. Is designed to emit light.

Further, in the second embodiment, a light source having the same wavelength distribution as the light emission of the Xe tube 37, which is the strobe light for exposure, is used for autofocus, and the object distance L and the reflected signal light amount P are used for each photographing. Then, the light absorption coefficient α was calculated. As a result, the GNo can be controlled in small increments depending on the state of water, and automatic exposure with proper exposure can be performed regardless of the difference between seawater and fresh water.

When it is determined that the camera is used underwater, it is also effective to simplify the Xe tube 37 of the flash unit 36 so that it emits a predetermined amount of light.

Further, as shown in FIG. 4, the projection lens 1
Two light receiving systems such as 5a, 15b and PSDs 16a, 16b are prepared so that the deviation of the reflected signal light can be corrected. Can also be taken into consideration, and correct distance measurement becomes possible.

In the underwater detector of the second embodiment, for example, a method of determining whether or not it is underwater based on the difference in the refractive index between water and air (see FIG. 9), and the difference in the resistance value are used. It is also applicable by using other methods such as a method of determining whether or not it is underwater.

Next, a camera according to the third embodiment of the present invention will be described.

FIG. 9 is a view showing the arrangement of the main parts of the camera of the third embodiment.

The camera of the third embodiment uses a passive autofocus for the distance measuring unit and applies the critical angle of the prism to the underwater detecting unit. The main part of this camera is the distance measuring unit 70, It is composed of an underwater detection unit 71, a CPU 72, and a strobe unit 73, and other configurations are the second.
Since it is the same as the embodiment, it is incorporated here and its description is omitted.

The distance measuring section 70 comprises light receiving lenses 74 and 75 for autofocus, sensor arrays 76 and 77, a cover glass 78, and a comparison circuit 79. The comparison circuit 79 is
It is a circuit for comparing the positional relationship of the light and shade of the images on the sensor arrays 76 and 77. Then, the comparison circuit outputs the comparison result to the CPU 72, and the CPU 72 obtains the subject distance from the comparison result. With the above-described configuration, the distance measuring unit 70 can perform distance measurement based on the principle of trigonometric distance measurement without projecting distance measuring light.

Further, the underwater detector 71 causes the light projected by the light projecting element 80 to enter the light receiving element 82 by utilizing the critical angle of the prism 81, and the incident light is detected by the light receiving section 83. Here, when water comes into contact with the surface of the prism 81 during underwater photography, the condition of the critical angle of the prism 81 collapses,
Since the light is not coupled, the incident light of the light receiving element 82 changes. The CPU 72 detects a difference in light intensity due to a change in incident light at this time via the light receiving unit 83, and detects whether or not it is underwater.

Then, the CPU 72 controls to switch the dimming amount of light emitted by the strobe unit 73 depending on the subject distance L and whether or not the environment in which the camera is used is underwater.

Further, in the air, a light beam incident on the sensor array 76 as shown in C in FIG. 10 is underwater because of the difference in refractive index between the water and the air with the cover glass 78 as a boundary. To the sensor array 76.

Therefore, this means that the distance measurement data changes between underwater and in air according to the law of refractive index even if the distance is the same. To simplify, the ratio of the refractive index n1 of water to the refractive index n2 of air is

[Equation 8] Therefore, from the distance measurement result L, the subject distance measurement Lw in water can be calculated by Lw = (3/4) · L ... (11).

The same concept applies to the second embodiment shown in FIG. 3 in which the method of judging whether or not the water is the water is used based on the difference between the refractive indexes of the water and the air. .

As described above, in the third embodiment,
Unlike the second embodiment shown in FIG. 3, only two autofocus lenses are required, so that the degree of freedom in camera layout is increased. Further, since energy for projecting light for distance measurement is not required, energy saving design is possible.

Further, as described above, according to each of the above-described embodiments, an amphibious camera which can automatically take a photograph with the correct exposure in water and in the air (land) is provided with a simple structure. be able to.

According to the above embodiment of the present invention, the following configuration can be obtained.

(1) In the camera provided with an underwater discriminating means for discriminating whether or not the use environment of the camera is underwater, and a strobe means for projecting auxiliary illumination light toward a subject at the time of photographing, the underwater discriminating means is provided. A camera equipped with a dimming calculation means for varying the dimming of the strobe means according to the output of the camera.

(2) The distance measuring light beam is projected onto the subject,
The light amount measuring means for measuring the reflected light amount, the calculating means for obtaining the light attenuation factor in water based on the distance measurement result, and the light amount measurement result, and the dimming calculation according to the light attenuation factor. The camera according to (1) above, characterized in that the means controls the strobe means.

(3) Luminance for judging subject brightness in a camera equipped with an underwater judging means for judging whether the environment in which the camera is used is underwater and a strobe means for projecting auxiliary illumination light toward the object at the time of photographing The determination level of the determination means is provided according to the output of the underwater determination means, the detection means and determination means for comparing the subject brightness with a predetermined determination level to determine the operation of the strobe means. A camera characterized by changing.

(4) In the camera described in (1) above, an optical correction member is inserted in the optical path of the photographing optical system in response to the characteristic signal.

[0095]

As described above, according to the present invention, in the underwater photography in which the camera holding is poor and the camera shake is likely to occur, the brightness determination level of the subject is switched so that the strobe light is easily emitted. The effect of can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a camera of a first embodiment.

FIG. 2 is a diagram showing light absorption characteristics in seawater.

FIG. 3 is a diagram showing a configuration of a camera of a second embodiment.

FIG. 4 is a diagram showing an optical system from light projection to light reception of a distance measuring unit in the second embodiment.

FIG. 5 is a block diagram showing a circuit inside the AFIC 17a in the second embodiment.

FIG. 6 is an example of an external view of a camera of a second embodiment.

FIG. 7 is a diagram showing an example of a general underwater photograph.

FIG. 8 is a flowchart showing the processing of the CPU 35 at the time of shooting with the camera (amphibious camera) of the second embodiment.

FIG. 9 is a diagram showing a configuration of a main part of a camera of a third embodiment.

FIG. 10 is a diagram showing how the incident angle of a light beam changes due to the difference in refractive index between water and air with the cover glass 78 as a boundary.

[Explanation of symbols]

1 CPU (Central Processing Unit) 2 Distance measuring unit 3 Underwater detection unit 4 Strobe unit 5 Exposure control unit 11 Distance measurement / Underwater detection unit 12 Subject 13 Xenon tube (Xe tube) 13a Mask 14 Light projecting lens 15a, 15b Light receiving lens 16a , 16b Semiconductor optical position detecting element (PSD) 17a, 17b Autofocus integrated circuit (AFI)
C) 18, 19 preamplifier 20, 21, 22, 23, 24, 25 transistor 26 integrating circuit 27, 28 compression diode 29, 30 buffer 31 constant current source 32, 33 transistor 34 resistor 35 CPU (Central Processing Unit) 36 strobe section 37 Xenon tube (Xe tube) 37a Reflector 38 Capacitor 39 Rectifier diode 40 DC / DC converter 41 Trigger circuit 42 Switch 43 Capacitor 44 Charging circuit 45 Rectifier diode 46 Trigger circuit 47 Release switch 48 AE section 49 Shooting lens 50 Aperture value input section 51 shutter

Continued front page    F-term (reference) 2H002 AB04 AB06 BB06 CD00 CD01                       CD04 CD11 FB38 HA11 JA01                 2H053 AA01 AB03 AD06 AD21 BA82                       CA41 DA01                 2H101 CC22 CC41 CC44

Claims (2)

[Claims] 1. A determination means for determining whether the shooting environment is on land or underwater, and a determination means for determining whether or not stroboscopic light emission is possible at the time of shooting based on the brightness of the subject. A camera is characterized in that the means switches the brightness determination level of the subject in the determination as to whether or not the stroboscopic light emission is possible according to the shooting environment determined by the determination means. 2. The brightness determination level of the subject is switched by the determination means in a direction that facilitates strobe emission when an underwater determination is made.
The listed camera.