JP3618017B2 - Camera with built-in flash - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a camera with a built-in flash equipped with a flashmatic mechanism for controlling the light emission of the strobe so that the exposure amount by the strobe light emission becomes an optimum exposure amount for photographing.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been proposed a camera that performs flashmatic shooting in daylight using a program shutter having a sector that functions as a diaphragm blade that operates based on a combination of an aperture and a shutter according to the brightness of a subject. In particular, a technique for adjusting the exposure amount by causing the strobe to emit light at a predetermined timing while the aperture of the program shutter gradually opens with time is effective for setting appropriate exposure.
[0003]
A conventional camera with a built-in strobe using such a technique is disclosed in Japanese Patent Publication No. 57-54777.
[0004]
In the conventional camera with a built-in strobe disclosed in the publication, a shutter operation as shown in the graph of FIG. 7 is performed by a program shutter in which the combination of the aperture and the shutter is determined based on the brightness of the subject (that is, the EV value). . The horizontal axis of this graph is time, and the vertical axis is the opening area of the shutter.
[0005]
First, at time t₀If the shutter starts to open at time t₀~ Time t₁During this period, the opening area of the shutter increases linearly and time t₁The opening area becomes maximum at time t₁~ Time t₂This maximum opening area is maintained during the period of₂At time t when the shutter starts to close₃Close completely.
[0006]
In this way, the amount of exposure by the strobe can be variably adjusted by causing the strobe to emit light in accordance with the movement of the shutter whose opening area gradually changes. That is, time t₁~ T₂If the strobe is fired during this period, the exposure amount by the strobe can be maximized, and the time t₀~ T₁If the strobe is caused to emit light during this period, a small exposure amount corresponding to the shutter opening area can be set.
[0007]
[Problems to be solved by the invention]
By the way, in the above conventional camera with a built-in flash, as the distance to the subject becomes shorter, the flash emission timing becomes t₀Approaching. However, at the time t when the shutter operation starts₀A certain time (t₀During the period Δt until + Δt), since the initial operation of the shutter is unstable, the change rate of the opening area varies. For this reason, the time t₀To the time (t₀When the strobe is caused to emit light during the period of + Δt), there has been a problem that the exposure amount error becomes very large.
[0008]
Further, when the strobe light emission period is set to the initial operation period (minimum period) Δt, a subject closer than the subject distance corresponding to the period Δt is overexposed and the atmosphere of the photograph is impaired. was there.
[0009]
The present invention has been made in view of such problems, and controls the light emission of the strobe so that the amount of exposure by the strobe is extremely small. An object is to provide a camera with a built-in strobe.
[0010]
[Means for Solving the Problems]
To solve the above problem,The camera with a built-in strobe according to the present invention has a sector that also serves as a diaphragm blade, and gradually opens with time, and a period T1 from when the opening operation of the program shutter starts until the strobe emits light. And a calculating means for calculating the period T1 and the light emitting period T2 so that the exposure amount by the strobe light emission becomes an appropriate exposure amount, and a control means for controlling the strobe light emission based on the period T1 and the light emitting period T2. The calculating means calculates the shutter opening area for setting the light emission period T2 as a maximum time and the exposure amount by the strobe light emission of the maximum time corresponding to the subject distance. The period calculated until the opening area is set as the period T1, and the period calculated by the first calculator When T1 is shorter than the minimum period, the light emission period T2 is decreased from the maximum time by a time T3, and the opening area of the shutter for setting the exposure amount by the strobe light emission in the reduced light emission period to an appropriate exposure amount is set as the subject. A second calculation unit that repeats the process of calculating the period corresponding to the distance and setting the period until the opening area as the period T1 while increasing T3 until the period T1 becomes longer than the minimum period. It is characterized by.
[0014]
Here, the minimum period may be a period from when the opening operation of the program shutter is started until the opening operation is stabilized.
[0018]
[Action]
The present inventionofAccording to the camera with a built-in strobe, the calculation means calculates the period T1 from when the opening operation of the program shutter starts until the strobe emits light and the light emission period T2 of the strobe. The computing means includes a first computing unit and a second computing unit, and first the processing of the first computing unit is performed. The first calculation unit calculates the shutter opening area for setting the exposure amount by the stroboscopic light emission of this maximum time to the appropriate exposure amount in correspondence with the subject distance, with the light emission period T2 as the maximum time. A period until the opening area is reached is a period T1.
[0019]
Here, when the period T1 calculated by the first calculation unit is shorter than the minimum period, the processing of the second calculation unit is performed. That is, in the second calculation unit, the light emission period T2 is decreased from the maximum time by a predetermined time T3. Then, the opening area of the shutter for setting the exposure amount by the strobe light emission in the reduced light emission period to an appropriate exposure amount is calculated in correspondence with the subject distance, and the period until reaching the opening area is set as a period T1. When the period T1 obtained in this way is equal to or shorter than the minimum period, the light emission period T2 is gradually decreased by increasing the predetermined time T3 and repeating the above process.
[0020]
Then, the control means controls the strobe light emission based on the period T1 and the light emission period T2 calculated by the first or second calculation means.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing an appearance of a camera with a built-in strobe according to an embodiment. As shown in this figure, this camera with built-in flash has a shutter button 11 disposed at the upper end of a substantially rectangular parallelepiped camera body 10 and a lens barrel 13 with a lens 12 incorporated in the center of the front surface of the camera body 10. . A projector 14, a finder 15, a light receiver 16, and a strobe 17 are disposed on the upper front of the camera body 10 from the left side of the figure. Here, the projector 14 and the light receiver 16 constitute a distance measuring unit that measures the distance to the subject based on the principle of triangulation, for example.
[0022]
In addition, on the right side of the lens barrel 13 on the front surface of the camera body 10, a photometry unit 18 for measuring the external light luminance in the photographing field of view is incorporated. The photometry unit 18 includes an incident window 18a formed on the surface of the camera body 10, a lens 18b disposed inside the incident window 18a, and a light receiving element 18c having a light receiving surface disposed in the vicinity of the imaging position of the lens 18b. And.
[0023]
Since the light receiving surface of the light receiving element 18c is shifted from the imaging position of the lens 18b, a complete subject image is not formed on the light receiving surface of the light receiving element 18c, and the entire photographing field including the subject is not formed. The average outside light quantity is detected by the light receiving element 18c. Further, a shutter 19 having a diaphragm spring sector that gives a necessary exposure amount to the film is incorporated on the optical axis of the lens 12 inside the camera body 10.
[0024]
Furthermore, a specific configuration of a strobe light control unit for controlling the light emission timing of the strobe 17 is shown in the block diagram of FIG. This strobe light control unit obtains an optimum exposure for photographing based on the distance to the subject measured by the projector 14 and the light receiver 16 and the external light luminance in the photographing field measured by the photometry unit 18. Controls the flash light emission. The strobe light control unit is realized by so-called program control in which the CPU 20 executes a control program 21 a written in the ROM 21.
[0025]
The CPU 20 is given a half-press signal and a full-press signal from the shutter button 11. Upon receiving the half-press signal from the shutter button 11, the CPU 20 gives a control signal for measuring the distance to the subject to the projector 14, and measures the external light luminance in the photographing field for the photometry unit 18. Give a control signal. In response to these control signals, the projector 14 (and the light receiver 16) and the photometry unit 18 perform distance measurement and photometry, and give these measurement results to the CPU 20. The CPU 20 that has received the full-press signal from the shutter button 11 gives a control signal for performing strobe light emission to the strobe 17 and gives a control signal for opening and closing the shutter 19.
[0026]
The strobe 17 automatically emits strobe light in accordance with the opening timing of the shutter 19. The shutter 19 is a programmed shutter whose combination of aperture and shutter is determined by the EV value, and performs the shutter operation shown in FIG.
[0027]
In FIG. 3A, the time point t at which the shutter 19 starts to open.₀A certain time (t₀The period Δt until + Δt) is an initial operation period in which the operation is unstable, although the opening area increases almost proportionally with time. At this point (t₀+ T) when the opening area of the shutter 19 becomes maximum₁In the period up to, the opening area of the shutter 19 increases in proportion to the time. Time t₁To time t₂During this period, the shutter 19 maintains the maximum opening area. Then, the shutter 19 is₂At the time t₃Close completely.
[0028]
As shown in the timing chart of FIG. 3B, the light emission control of the strobe 17 is performed by variably controlling the period T1 from when the shutter 19 starts to open until the strobe 17 emits light, and the light emission period T2 of the strobe 17. It is realized by. That is, if the light emission period T2 is changed, the amount of strobe light changes, so that the exposure amount by the strobe 17 can be changed. Even if the light emission period T2 is constant, the period T1 is₀And time t₁Since the opening area of the shutter 19 is changed, the exposure amount by the strobe 17 can be changed.
[0029]
Such determination of the period T1 and the light emission period T2 is performed by first calculating the period until the aperture area corresponding to the distance to the subject measured by the distance measuring unit (the projector 14 and the light receiver 16) is obtained. Is T1. When the period T1 is shorter than the period Δt until the opening operation of the strobe 17 is stabilized (T1 <Δt), the period T1 is set to Δt (that is, T1 = Δt), and the light emission period T2 of the strobe 17 is set. The maximum time for full light emission is changed to be shorter.
[0030]
Next, a specific flow of the light emission control of the strobe 17 performed in the present embodiment will be described with reference to the flowcharts of FIGS. 4 and 5 and the graphs of FIGS. Here, the graphs of FIGS. 6A and 6B show the apex of the strobe guide number corresponding to the light emission period T2 with the abscissa apex value (AV value) corresponding to the shutter opening area corresponding to the period T1 as the horizontal axis. It is the graph which made the value (GV value) the vertical axis | shaft. In addition, two types of light emission control methods are employed. The first light emission control method is shown in FIGS. 4 and 6A, and the second light emission control method is shown in FIGS. 5 and 6B, respectively. ing. All the light emission control methods are performed by the CPU 20 based on the control program 21a described above.
[0031]
First, the process of the first light emission control method will be described using the flowchart of FIG. 4 and the graph of FIG. When the photographer holds the camera toward the subject and half-presses the shutter switch 11, the apex value (BV value) of the external light luminance measured by the photometry unit 18 is obtained, and the light projector 14 and the light receiver 16 reach the subject. The distance (D) is measured. Then, a correction value (OFS value) is obtained from a predetermined correction table using the external light luminance (BV) and the distance (D) as parameters. This correction table is written in the ROM 21 (not shown), and is a look-up table that defines the relationship of the OFS value from the external light luminance (BV) and the distance (D). The FL value is calculated by substituting the OFS value thus obtained into the following equation (1) (step 100).
FL = log₂OFS… ▲ 1 ▼
Then, the aperture value AV (MIN) of the maximum aperture of the program shutter determined from the external light luminance (BV) and the film sensitivity is obtained from the lookup table (not shown) in the ROM 21 (step 101).
[0032]
Next, the maximum value GV (MAX) of the GV value is calculated by substituting the guide number (GNo.) In ISO 100 when the flash is fully emitted into the following equation (2) (step 102).
GV = 2log₂GNo. … ▲ 2 ▼
Further, the DV value is obtained by substituting the distance (D) to the subject into the following equation (3).
[0033]
DV = -2log₂D… ▲ 3 ▼
Next, by substituting the FL value obtained in step 100, the GV value obtained in step 102, the apex value (SV) of film sensitivity, and the DV value into equation (4), the aperture value (AV value) of the program shutter is set. Is calculated (step 103).
AV = GV + SV + DV−FL−5 (4)
The coordinate point indicated by the GV value and the AV value thus obtained is either on the line segment 130 in the graph of FIG. 6A or on the right extension of the line segment 130. More specifically, the coordinate point is on a line segment 130 represented by GV = GV (MAX) and AV (MIN) ≦ AV ≦ AV (MAX), or GV = GV (MAX ) And AV (MAX) <A within the range of AV.
[0034]
Next, the AV value obtained in step 103 is compared with the AV value (AV (MAX)) when the period T1 is set to the minimum period (step 104). When the AV value is larger than AV (MAX), , AV value is AV (MAX) (step 105). That is, when the coordinate point indicated by the GV value and the AV value is on the right side of the line segment 130 in the graph of FIG. 6A, in other words, the coordinate point is GV = GV (MAX) and AV (MAX) < If it is within the range of AV, the AV value is forcibly positioned at the right end (AV = AV (MAX)) of the line segment 130. By this process, the period T1 becomes equal to the minimum period (initial operation period) Δt (see FIG. 3A).
[0035]
Next, the GV value is calculated by substituting the AV value, the already obtained SV value, DV value, and FL value into the following equation (5) (step 106).
GV = AV−SV−DV + FL + 5 (5)
The coordinate point indicated by the GV value and the AV value obtained in this way is either on the line segment 131 or on the lower extension of the line segment 131 in the graph of FIG. More specifically, the coordinate point is on a line segment 130 expressed by AV = AV (MAX) and GV (MIN) ≦ GV ≦ GV (MAX) or AV = AV (MAX) And it exists anywhere in the range of GV <GV (MIN). By this process, the light emission period T2 of the strobe 17 is shortened.
[0036]
Next, the GV value obtained in step 106 is compared with the GV value (GV (MIN)) when the light emission period T2 is set to the shortest light emission time during which the strobe 17 can operate (step 107). If it is smaller than GV (MIN), the GV value is set to GV (MIN) (step 108). That is, when the coordinate point indicated by the GV value and the AV value is below the line segment 131 of the graph of FIG. 6A, the GV value is positioned at the lower end (GV = GV (MIN)) of the line segment 131. . By this processing, the light emission period T2 becomes the shortest light emission period during which the strobe 17 can operate.
[0037]
Next, in step 104, if the AV value is equal to or less than AV (MAX), the AV value is compared with AV (MIN) (step 109). If the AV value is smaller than AV (MIN), the AV value is set to AV (MIN) (step 110).
[0038]
Here, the AV value is smaller than AV (MIN) when the GV value and the coordinate point indicated by the AV value are on the left side of the line segment 130 in the graph of FIG. That is, this coordinate point is in the range of GV = GV (MAX) and AV <AV (MIN).
[0039]
Then, according to the processing of step 110, the GV value and the coordinate point indicated by the AV value are positioned at the left end of the line segment 130 by forcibly setting the AV value to AV (MIN). Therefore, by this process, the period T1 becomes the period (t₁-T₀(See FIG. 3A).
[0040]
When the processing of step 108 or step 110 is completed, if the GV value is GV (MIN) or more in step 107, or if the AV value is AV (MIN) or more in step 109, the first light emission control method This process ends.
[0041]
Next, the process of the second light emission control method will be described using the flowchart of FIG. 5 and the graph of FIG. When the photographer holds the camera toward the subject and half-presses the shutter switch 11, the apex value (BV value) of the external light luminance measured by the photometry unit 18 is obtained, and the light projector 14 and the light receiver 16 reach the subject. The distance (D) is measured. Then, a correction value (OFS value) is obtained from a predetermined correction table using the external light luminance (BV) and the distance (D) as parameters. This correction table is written in the ROM 21 (not shown), and is a lookup table that defines the relationship of the OFS value from the external light luminance (BV) and the distance (D). The FL value is calculated by substituting the OFS value thus obtained into the equation (1) (step 110).
[0042]
Then, the aperture value AV (MIN) of the maximum aperture of the program shutter determined from the external light luminance (BV) and the film sensitivity is obtained from a table (not shown) written in the ROM 21 (step 111).
[0043]
Next, a value AVLIM slightly smaller than the AV value (AV (MAX)) when the period T1 is set to the minimum period Δt is determined (step 112). AVLIM may be a constant value or a value based on AV (MIN) or AV (MAX). However, it is a condition that the accuracy of the opening operation of the shutter 19 is a portion between the period T1 corresponding to AVLIM and the minimum period Δt. Then, the maximum value (GV (MAX)) of the GV value is obtained by substituting the guide number (GNo.) When the strobe is fully emitted into the equation (2) (step 113).
[0044]
Further, the DV value is obtained by substituting the distance (D) to the subject into the equation (3). Then, the AV value is obtained by substituting the FL value obtained in step 110, the GV value obtained in step 113, the film sensitivity (SV), and the DV value into the equation (4) (step 114).
[0045]
The coordinate point indicated by the GV value and AV value obtained in this way is either on the line segment 132 of the graph of FIG. 6B or on the extension of the right end of the line segment 132. More specifically, the coordinate point is on the line segment 132 represented by GV = GV (MAX) and AV (MIN) ≦ AV ≦ AV (MAX), or GV = GV (MAX). And it exists in the range of AV (MAX) <AV.
[0046]
Next, the AV value obtained in step 114 is compared with AV (MAX) (step 115). If the AV value is larger than AV (MAX), the GV value is calculated as (AV (MAX) −AVLIM)) (step 116).
GV = GV− (AV (MAX) −AVLIM) (6)
That is, when the coordinate point indicated by the GV value and the AV value is on the right side of the line segment 132 in the graph of FIG. 6B (AV (MAX) <AV), the GV value is on the line segment 133. (Or on the extension of the line segment 133). By this process, the light emission period T2 of the strobe 17 is shortened.
[0047]
Next, the GV value obtained in step 116 is compared with the GV value (GV (MIN)) when the light emission period T2 is set to the shortest light emission time during which the strobe 17 can operate (step 117). In the case of GV (MIN) or more, the AV value is obtained by substituting the GV value, the already obtained SV value, the DV value, and the FL value into the equation (4) (step 118). The coordinate point indicated by the GV value and the AV value obtained in this way is on one of the line segments 133 (or on the extension of the line segment 133) in the graph of FIG. Then, the process returns to step 115.
[0048]
Thereafter, by repeating the processing from step 115 to step 118 until the AV value becomes equal to or less than AV (MAX), the line segment where the coordinate point indicated by the GV value and the AV value is located is changed from the line segment 134 to the line segment. 135 → Change to line segment 136 step by step.
[0049]
Each of the line segments 133 to 136 is based on a combination of the GV value and the AV value at a portion where the opening operation accuracy of the shutter 19 is good. That is, each of the line segments 133 to 136 is based on a combination of the GV value and the AV value when the minimum period Δt shown in FIG.
[0050]
As a result, the GV value and AV value satisfying the above formulas (4) and (5) are determined on any line segment, and the light emission control of the strobe 17 is performed based on these values, whereby exposure by the strobe 17 is performed. Quantity control can be performed with extremely high accuracy.
[0051]
If the GV value is smaller than GV (MIN) in the comparison process in step 117, the GV value is set to GV (MIN) (step 119). That is, when the coordinate point indicated by the GV value and the AV value is below the dotted line 136 in the graph of FIG. 6B (that is, GV <GV (MIN)), the GV value is positioned on the dotted line 136. It is. By this processing, the light emission period T2 becomes the shortest light emission period that can be controlled by the flash unit 17.
[0052]
Further, the AV value is obtained by substituting the FL value obtained in step 110, the GV value obtained in step 119, the film sensitivity (SV), and the DV value into the formula (4) (step 120). The coordinate point indicated by the GV value and the AV value obtained in this way is on one of the line segments 136 (or on the extension of the line segment 136) in the graph of FIG.
[0053]
Next, the AV value obtained in step 120 is compared with AV (MAX) (step 121). If the AV value is larger than AV (MAX), the AV value is set to AV (MAX) (step 122). ). That is, when the coordinate point indicated by the GV value and the AV value is on the right side of the line segment 136 in the graph of FIG. 6B (that is, AV (MAX) <AV), this point is placed at the right end of the line segment 136. It is positioned. By this process, the period T1 becomes Δt (see FIG. 3A).
[0054]
If the AV value is less than AV (MAX) in step 115, the AV value is compared with AV (MIN) (step 123). If the AV value is smaller than AV (MIN), the AV value is AV (MIN) is set (step 124). The AV value is smaller than AV (MIN) when the GV value and the coordinate point indicated by the AV value are on the left side of the line segment 132 in the graph of FIG. 6B (that is, AV <AV (MIN) In the process of step 124, the AV value is AV (MIN) and the GV value and the point indicated by the AV value are positioned at the left end of the line segment 132. By this process, the period T1 is changed to the period (t₁-T₀)
[0055]
When the process of step 122 or step 124 is completed, when the AV value is equal to or less than AV (MAX) in step 121, or when the AV value is equal to or greater than AV (MIN) in step 123, the second light emission control. The processing of the method ends.
[0056]
The optimum AV value and GV value for the light emission control of the strobe 17 are determined by the processing of the first light emission control method or the processing of the second light emission control method described above. The AV value corresponds to the period T1 from when the shutter 19 starts to open until the strobe 17 emits light, and the GV value corresponds to the light emission period T2 of the strobe 17. Therefore, by determining these values, the period T1 and the light emission are determined. The period T2 is fixed.
[0057]
The present invention is not limited to the present embodiment described above, and various modifications can be made. For example, in the present embodiment, the light emission control processing of the strobe 17 is configured by so-called program control executed by the CPU 20 based on the control program 21a written in the ROM 21, but the same light emission control processing is performed by hardware. You may make it carry out by a circuit.
[0058]
In this embodiment, the distance to the subject is measured by the active distance measuring method using the projector 14 and the light receiver 16, but the passive distance measuring method may be used.
[0059]
【The invention's effect】
As explained in detail above, the present inventionofThe camera with a built-in strobe has a program shutter and a period T1 so that the exposure amount by the strobe light emission is an appropriate exposure amount between the period T1 from when the opening operation of the program shutter starts until the strobe light is emitted and the strobe light emission period T2. And a calculation means for calculating the light emission period T2, and a control means for controlling the strobe light emission based on the period T1 and the light emission period T2 calculated by the calculation means. In the calculation means, first, the first calculation unit calculates the period T1 when the light emission period T2 is set to the maximum time (full light emission), and when the calculated period T1 is shorter than the minimum period (initial operation period). The second calculation unit calculates the light emission period T2 with the period T1 as the minimum period or the vicinity thereof.
[0060]
Thus, even when the period T1 calculated by the first calculation unit is shorter than the minimum period, the period T1 is set to the minimum period or the vicinity thereof by the second calculation unit, and therefore the opening operation is unstable in the period T1. It will not be shorter than the minimum period. For this reason, the exposure amount can be adjusted with high accuracy. In the second calculation unit, a light emission period T2 shorter than the maximum time is calculated. For this reason, the overexposure does not occur even at a short distance, and an excellent effect is exhibited that the subject can be photographed without losing the atmosphere.
[0061]
In particular,Change the flash emission period T2 step by stepByThe capacity of the memory for storing the relationship between the light emission amount GV and the light emission period T2 can be reduced, and the size and weight can be reduced.
that's all
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating an appearance of a camera with a built-in strobe according to an embodiment.
FIG. 2 is a block diagram illustrating a configuration for performing strobe light emission control.
FIG. 3 is a diagram illustrating shutter opening timing and strobe light emission timing.
FIG. 4 is a flowchart showing a flow of strobe light emission control processing.
FIG. 5 is a flowchart showing a flow of strobe light emission control processing.
FIG. 6 is a graph showing processing for controlling light emission of a strobe.
FIG. 7 is a graph showing a relationship between an opening area of a shutter and time.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Shutter button, 14 ... Light projector, 16 ... Light receiver, 17 ... Strobe, 18 ... Photometry part, 19 ... Shutter, 20 ... CPU (calculation means, control means), 21 ... ROM, 21a ... Control program (calculation means, Control means).

Claims (2)

A program shutter that has a sector that also serves as a diaphragm blade and opens gradually over time,
Calculation means for calculating the period T1 and the light emission period T2 so that the exposure amount by the strobe light emission becomes an appropriate exposure amount during the period T1 from when the opening operation of the program shutter starts until the strobe light is emitted and the light emission period T2 of the strobe light. When,
Control means for controlling strobe light emission based on the period T1 and the light emission period T2,
The computing means calculates the light emission period T2 as a maximum time, calculates an opening area of a shutter for setting the exposure amount by the strobe emission of the maximum time to an appropriate exposure amount, corresponding to the subject distance, and calculates the opening area. A first calculation unit that sets the period until the period T1 as the period T1,
When the period T1 calculated by the first calculation unit is shorter than the minimum period, the light emission period T2 is decreased from the maximum time by the time T3, and the exposure amount by strobe light emission in the reduced light emission period is set appropriately. A process of calculating an opening area of a shutter for making an exposure amount corresponding to a subject distance and setting a period until the opening area becomes the period T1 is performed until the period T1 becomes longer than the minimum period. And a second arithmetic unit that repeats the process while increasing the number. The camera with a built-in strobe according to claim 1, wherein the minimum period is a period from when the opening operation of the program shutter starts until the opening operation is stabilized.

Images