JPH07120801A - Camera-shake preventing camera - Google Patents

Abstract

PURPOSE:To prevent the useless consumption of power and a time lag caused by vibration proof control by making a vibration proof means inoperative when it is predicted that a sufficient vibration proof effect is not obtained. CONSTITUTION:In this camera-shake preventing camera having the vibration proof means executing correction for minimizing influence by a camera-shaking quantity at the time of exposing based on the measured camera-shaking quantity or camera-shake information, a vibration proof effect deciding means 1 deciding whether the camera-shaking quantity at the time of exposing is at an allowable level or not when the vibration proof means 2 is actuated and an exposing means 3 executing control for an exposure without actuating the vibration proof means 2 when the vibration proof effect deciding means 1 judges that an effect is not obtained even if the vibration proof means 2 is actuated, are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-shake camera.

[0002]

2. Description of the Related Art An anti-vibration technique has been conventionally known in which a camera shake is detected and a taking lens is driven by an amount corresponding to the detected shake amount to correct the shake. However, such an anti-vibration technique has the drawbacks of high cost and a large camera configuration. Therefore, a compact camera or the like uses a simple anti-vibration technique for opening a shutter by detecting a timing with a small blur. For example, Japanese Patent Laid-Open No. 3-218672 discloses a technique of detecting a blur amount, predicting the blur amount during exposure based on the detected value, and permitting exposure if the predicted value is equal to or less than the permissible blur amount. is doing. In addition, Japanese Patent Application No. 4-011225
In the publication, the blur amount Y during exposure is calculated from the time series data X (i) of the blur signal and the prediction coefficient A (i).

[0003]

[Equation 1] The technique of performing exposure permission or image stabilization drive based on the predicted blur amount Y is disclosed.

[0004]

However, at low shutter speeds, the prediction time becomes long, so that the accuracy cannot be ensured and a sufficient anti-vibration effect cannot be obtained in many cases. Further, in a vehicle or a ship, unpredictable vibrations are given to the camera and the photographer, so that it is often impossible to obtain a sufficient vibration damping effect.

Further, in the case of photographing a moving object, the camera follows the object and cannot obtain a sufficient image stabilizing effect. The present invention has been made by paying attention to such a problem, and an object of the present invention is to deactivate the anti-vibration means when it is expected that a sufficient anti-vibration effect cannot be obtained. Prevent consumption,
An object of the present invention is to provide an anti-shake camera that can prevent a time lag due to image stabilization control, and can warn a photographer that a sufficient image stabilization effect cannot be obtained, so as to encourage more careful shooting.

[0006]

In order to achieve the above-mentioned object, the anti-shake camera of the present invention is designed so that the influence of the measured camera shake amount or the camera shake amount based on the camera shake information is minimized during exposure. In an anti-shake camera having an anti-shake device that corrects so that when the anti-shake device is actuated, an anti-shake effect determination unit that determines whether or not the amount of blur during exposure is within an allowable value Exposure control means for controlling exposure so as to perform exposure without operating the image stabilization means when the blur effect determination means determines that the image stabilization means has no effect.

Further, the anti-shake camera of the present invention has an anti-vibration means for correcting the influence of the measured amount of camera shake or the amount of camera shake predicted based on the camera shake information to a minimum during exposure. In the anti-shake camera, the anti-shake effect determination unit determines whether the amount of shake during exposure is within an allowable value when the anti-shake unit is activated, and the anti-shake effect determination unit determines the anti-shake effect. A warning means is provided for giving a warning to the photographer when it is determined that the operation is not effective.

[0008]

In other words, the anti-shake camera of the present invention determines whether or not the amount of shake at the time of exposure is within the permissible value, and when it is determined that the anti-vibration means is not effective, The exposure is controlled without operating the shaking means.

Further, the anti-shake camera of the present invention determines whether or not the amount of shake at the time of exposure is within an allowable value, and shoots when it is determined that the operation of the image stabilizing means has no effect. Warn people.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is a configuration diagram showing the basic concept of the anti-shake camera according to the present embodiment. In the figure, the anti-shake camera has an anti-shake effect determination means 1 for determining whether or not a sufficient anti-shake effect can be obtained from shutter speed, shake information, shooting mode information, etc., and anti-shake control based on the shake information. It is provided with the image stabilizing means 2 for performing the exposure and the exposing means 3 for actually performing the exposure operation. Then, when it is determined in the image stabilization effect determination means 1 that the image stabilization effect of the image stabilization means 2 is obtained, the image stabilization means 2 is activated and then the exposure means 3 performs exposure, and conversely the image stabilization effect is obtained. When it is determined that the exposure is not performed, the exposure means 3 performs the exposure without operating the image stabilizing means 2.

FIG. 1 (b) is a conceptual diagram when the present invention is applied to an image stabilization technique for driving a taking lens to correct blur. The point different from FIG. 1A is that when the image stabilization effect determination means 2 determines that the image stabilization effect of the image stabilization means 2 is obtained, exposure is performed while operating the image stabilization means 2. Only points.

FIG. 2 is a block diagram showing another basic concept of this embodiment. In the figure, an anti-shake camera has a shutter speed determination unit 4 that determines a shutter speed from photometric results, film sensitivity information, and the like, and image stabilization that determines whether a sufficient anti-shake effect is obtained according to the shutter speed. An effect determining unit 1, an image stabilizing unit 2 that performs image stabilizing control based on shake information, an exposing unit 3 that actually performs an exposure operation, and a warning unit 5 that informs a photographer that the image stabilizing unit 2 does not operate. It is composed of.

In other words, in this anti-shake device, when the shutter speed is low and a sufficient anti-vibration effect is not expected, the warning means 5 warns the photographer to that effect and the anti-vibration means 2 is not activated. If the exposure control is not performed, the image stabilization means 2 is activated, and then the exposure means 3 controls the exposure.

Therefore, when the anti-vibration effect cannot be expected, it is possible to remind the photographer by avoiding the waste of electric power in the anti-vibration means 2 and by giving a warning to the photographer.

FIG. 3 is a configuration diagram in which the basic concept described above is realized by using a microcomputer (CPU). In the figure, the CPU 111 executes sequence control of the entire camera. R1 and R2 are two-step release switches, R1 is a first release switch, and R2 is a second release switch. Blur sensor unit 101
Is a device that outputs a shake displacement in response to a request from the CPU 111. For example, a combination of a light emitting diode and a photodiode disclosed in Japanese Patent Application No. 4-149673, an acceleration sensor, a CCD sensor, or the like should be used. You can The photometric unit 102 is a sensor that measures the brightness of the subject. The zoom position detection unit 103 detects the focal length f of the zoom and uses an absolute position encoder or P.I. I. It is possible to use a means for counting pulses and calculating a relative position.

The AF distance measuring section 104 is a TTL phase difference type CCD sensor in a single-lens reflex camera, and an active AF type infrared projection PSD light receiving element can be used in a lens shutter. The DX reading unit 105
It is a DX contact piece in a cartridge chamber of a camera body (not shown). The PCV 112 is a ceramic oscillator that produces a warning sound. A diaphragm motor Md113, a lens drive motor M114, and a mirror up motor Mm115 are connected to the motor driver 106. This is for a single-lens reflex camera, and Md11 for a lens shutter.
3, Mm115 can be omitted. The shutter 107, which is controlled by a plunger and a motor, is driven by a shutter drive unit 108. Reference numeral 109 is a strobe emission control unit, and 110 is various shooting mode selection units.

FIG. 4 shows a first example applied to a compact camera.
It is a flow chart which shows operation of an example. In the figure, first, when R2 is turned on, this flowchart starts. Next, the DX, zoom position, and photometric value are read and exposure calculation is performed (steps S1 to S4). Since the shutter speed is calculated by the exposure calculation in step S4, when the shutter speed is slower than the reciprocal 1 / l of the zoom focal length, the PCV 112 issues a warning sound to alert the photographer (steps S5 and S6). This is to give a warning to the photographer so as to urge the photographer to be careful not to cause blurring. Of course, PCV112
Needless to say, the warning may be given by an LED or the like in the finder. The AF sequence is performed by the AF distance measuring unit 1.
The measured value is read from 04, and the lens extension amount is determined by the AF calculation (steps S9 and S10).

Next, if R2 is turned on in step S12, the sequence moves to the photographing sequence. If R2 is not turned on, the above cycle is repeated until R1 is turned off (step S13).

In the photographing sequence, after the lens is driven (step S11), if the shutter speed is higher than a predetermined shutter speed at which an anti-vibration effect is obtained, the "blur amount evaluation" subroutine is used to measure the blur amount and determine whether to permit the shutter. (Steps S14 and S17). As will be described in detail later, here, when the shutter permission determination is OK,
The subroutine ends. Conversely, if the shutter speed is slower than the predetermined shutter speed, the photographer is warned that the image stabilization effect cannot be obtained (step S20).

If the shutter permission determination is OK or the shutter speed is slower than a predetermined value, the shutter 107
Is driven (step S18). After that, the film is wound up and the release sequence is finished (step S19).

Next, referring to FIG. 5, step S17 of FIG.
An example of the “blur amount evaluation” subroutine shown in FIG. First, read the shutter speed (step S21),
Next, the bleeder data is read (step S22). The blur data stores blur data for at least the shutter speed. For example, if the shutter speed is 1/32, blur data up to 1/32 seconds before the present is stored, for example, every 1 ms. In the next blurring amount calculation, the blurring amount that is currently occurring is calculated by subtracting the past blurring amount for the shutter speed from the current blurring amount, and taking an absolute value (step S23).

The blur data referred to here corresponds to camera position information and again information. It goes without saying that the calculation method of the blur amount is different if the blur data corresponds to the speed information and the acceleration information of the camera.

Next, a prediction calculation of the blur amount during exposure is performed (step S24). For this prediction calculation, for example, the prediction calculation disclosed in Japanese Patent Application No. 4-112225 may be used. Next, the blur amount is corrected by the focal length of the camera (step S25). This is because the longer the focal length, the greater the amount of blur on the film surface affects the blur of the camera. The method of correction is simply shake amount the focal length f ₀
If it corresponds to, it is sufficient to multiply by f / f ₀ . Of course, when the TTL or AF sensor is used as the blur sensor, the blur amount already includes the focal length information, so that the zoom value correction is not necessary.

Next, it is judged whether the corrected blur amount is less than a predetermined value, and if it is less than the above, the process returns, that is, the shutter opening operation is performed (step S26). When it is not less than the predetermined value, the blur data is measured again and the above is repeated.

FIG. 6 is a flow chart showing the operation of the second embodiment of the present invention. In this example, the difference from FIG. 4 is that even when the shutter speed is faster than a predetermined value, the blur data is read (step S15), it is determined whether or not the blur amount is below a predetermined level, and if it is above a predetermined level,
When shooting a moving object, or considering shooting on a car or a ship, the amount of blur is not evaluated, but only a point of permitting shutter drive after a warning to that effect (step S20). Is.

The present invention can be applied not only to the above-described simple image stabilization technique, but also to an image stabilization technique for driving a taking lens to correct blur. Needless to say.

Further, the selection result of various shooting modes such as the continuous shooting mode, the moving object prediction mode, the night view mode, the zoom information, the shutter speed information, the blur information, and the stroboscopic light emission information are comprehensively determined to obtain the image stabilization effect. It is also possible to judge.

[0028]

As described in detail above, according to the present invention, when it is determined that the image stabilization effect cannot be obtained, the image stabilization function is disabled, so that waste of power is prevented. It is possible to prevent a time lag due to vibration control. Further, in the above case, since the means for warning that the anti-vibration effect cannot be obtained is provided, the photographer can photograph with more caution.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a basic concept of an anti-shake camera according to an embodiment.

FIG. 2 is a configuration diagram showing another basic concept.

FIG. 3 is a configuration diagram in which the basic concept shown in FIG. 1 is realized by using a microcomputer.

FIG. 4 is a flowchart showing the operation of the first embodiment.

5 is a flowchart showing steps of a "blur amount evaluation" subroutine shown in FIG. 4. FIG.

FIG. 6 is a flowchart showing the operation of the second embodiment.

[Explanation of symbols]

1 ... Anti-vibration effect determining means, 2 ... Anti-vibration means, 3 ... Exposure means,
4 ... Shutter speed determination unit, 5 ... Warning means.

Claims (3)

[Claims] 1. An anti-shake camera having an anti-shake unit that corrects the effect of the amount of hand shake based on the measured amount of hand shake or hand shake information so as to minimize it during exposure. When activated, the blur effect determining means determines whether or not the blur amount during exposure is within an allowable value, and the blur effect determining means determines that the anti-vibration means has no effect. An anti-shake camera, comprising: an exposure control unit that controls exposure so that the image stabilization unit does not operate. 2. An anti-shake camera having anti-shake means for correcting the influence of the measured camera shake amount or the camera shake amount predicted based on the camera shake information so as to minimize the effect during exposure. When the vibrating means is operated, the blur effect judging means for judging whether or not the blur amount at the time of exposure is within the allowable value, and the blur effect judging means is effective even if the vibrating means is operated. An anti-shake camera, comprising: a warning unit that warns the photographer when it is determined that there is no camera shake. 3. The blur effect determining means determines the operating effect of the image stabilizing means based on at least one of shutter speed information, blur information, zoom information, flash emission information, and shooting mode information. The anti-shake camera according to claim 1, wherein: