JPH05241064A - Camera provided with soft focusing function - Google Patents

Abstract

PURPOSE:To automatically obtain an image with soft focusing effect when it is required by utilizing the function of a camera in which the soft focusing image can be obtained. CONSTITUTION:A first judging means 10 (system controlling part) judging whether a photographing condition set requires blur correction by a blur correcting means 4 (actuator for correcting blur) or not, and a second judging means 10 (system controlling part) judging whether photographing magnification set is larger than a specified magnification or not are provided, and a blur correcting lens 3 is shifted exceeding a shifting area at the time of executing the blur correction by means of the blur correcting means 4 when the first judging means judges that the blur correction is not required and the second judging means judges that the photographing magnification is larger than the specified magnification.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera capable of obtaining an image having a soft focus effect.

[0002]

2. Description of the Related Art Most photographic lenses usually suppress aberrations as much as possible in order to achieve a sharp image and a high resolution. However, on the other hand, it is sometimes said that the lens has no habit and has no taste.

On the other hand, with a lens having a large amount of aberration, the light emitted from one point of the subject does not necessarily converge to one point when the light passes through the lens and forms an image. Becomes Breaking the focus like this is called soft focus.
A soft focus lens was created for this purpose, and is used for portraits for women who prefer a particularly soft depiction.

In order to obtain the soft focus effect, in addition to using a soft focus lens having a large amount of aberration as described above, a dedicated attachment is attached to the front or the middle of the taking lens, or a part of the taking lens group is replaced with another attachment. It is obtained by shifting a predetermined amount with respect to a portion or by zooming a lens by a small amount during exposure.

[0005]

In order to obtain the soft focus effect, there are several conventional methods as described above, but all of them must be manually operated by the photographer. Therefore, the photographer cannot concentrate on the framing, and the cost is high. It is an object of the present invention to utilize a conventional function of a camera to automatically obtain an image having a soft focus effect when needed.

[0006]

According to the present invention, in a camera having a shake correcting means (4) for shifting a shake correcting lens (3) to prevent camera shake, the set photographing condition is shaken by the shake correcting means. A first judging means (10) for judging whether or not the photographing condition requires correction and a second judging means (10) for judging whether or not the set photographing magnification is larger than a predetermined magnification are provided. When it is determined that the shake correction is unnecessary by the first determination unit and the photographing magnification is larger than the predetermined magnification by the second determination unit, the shift correction unit shifts the shake correction lens when performing the shake correction. It is configured to obtain an image having a soft focus effect by shifting beyond the area. Also,
The photographing condition that requires the shake correction to be judged by the first judging means is characterized in that the set shutter speed is equal to or more than the shake limit second.

[0007]

In the structure of the present invention, when the image pickup condition is such that the image shake correction is unnecessary and the image is taken at a predetermined image pickup magnification or more, the unused image blur correction lens exceeds the shift area for image blur correction. The image is automatically shifted to the position and an image having a soft focus effect is obtained by utilizing the aberration change obtained by this lens shift.

[0008]

FIG. 1 is a schematic sectional view showing an embodiment of a camera with a soft focus function according to the present invention, which is composed of a camera body 1 having an image stabilizing function and an interchangeable lens 2. In the interchangeable lens 2, a shake correction lens 3 and a shake correction actuator 4 as a shake correction unit that shifts the lens 3 to perform shake correction are incorporated. In the present invention, the soft focus effect is obtained by using the shake correction lens 3 and the shake correction actuator 4.

FIG. 2 is a block diagram showing an embodiment of a camera according to the present invention, in which various kinds of control of the camera are performed by a system controller 10 having a microcomputer configuration.

The system control unit 10 has a half-press switch SW1 which is turned on by a half-press operation of a release operation member.
And full-press switch SW turned on by full-press operation
2, a release section 11 for setting an exposure mode such as shutter priority or aperture priority, and an aperture value and shutter time for each mode, and a vibration caused by camera shake to detect the vibration. Shake detection sensor 13 that outputs the frequency data and amplitude data of the
, A photometry unit 14 for detecting the brightness of the subject, a focal length detection unit 15 for detecting the focal length of the taking lens, and a distance measuring unit 16 for detecting the distance from the focused subject to the optical center of the lens. And an exposure control unit 19 that controls the shutter drive unit 17 and the diaphragm drive unit 18 based on a command from the system control unit 10, and also drives the shake correction lens 3 described above based on a command from the system control unit 10. The shake correction actuators 4 are connected to each other.

Next, a processing procedure for obtaining the soft focus effect by the camera having this structure will be described with reference to the flowchart shown in FIG. This process is started by turning on the half-press switch SW1 of the release section 11. First, the focal length data f of the taking lens 2 is read from the focal length detector 15 (step S
1) Then, the shutter time data T set by the exposure factor setting unit 12 is read (step S2).

Next, the shutter speed T and the camera shake limit speed T
It is compared with c to determine which value is larger (step S3). The shake limit second Tc is represented by Tc = (1 / f) × 2 ⁿ , where n is zero or a positive real number. Generally, it is said that the handshake limit second is one part of the focal length.
= 0 ”, which is a value of about“ n = 1 ”for practical use.

When it is determined in step S3 that the shutter speed T is equal to or greater than the camera shake limit time Tc, shake correction is required under the set shooting conditions, so the shake correction lens 4 is used by the shake correction actuator 4. A known shake correction process of shifting to a position (first position) within a predetermined shift area is executed (step S4), and the process is ended. On the other hand, if it is determined in step S3 that the shutter speed T is smaller than the camera shake limit time Tc, shake correction is not necessary, and the soft focus effect is obtained by using the unused shake correction lens 3. .

First, the object distance data R from the distance measuring unit 16
(Step S5), shooting magnification β (= f / R)
Is calculated (step S6). Next, the shooting magnification β is 30
It is determined whether or not it is larger than 1 / (step S7). When the photographing magnification β is larger than 1/30, it means that the image is photographed in the up-sized state.
Then, the shake correction lens 3 is shifted to the second position (step S8), and an image having a soft focus effect is obtained by utilizing the aberration change caused by the lens shift. The second position is a position beyond the shift area in which the shake correction lens 3 is shifted when performing shake correction. This is because the aberration is small with the shift amount during shake correction, and the soft focus effect can hardly be expected.

When it is determined in step S7 that the photographing magnification β is 1/30 or less, or when the lens shift in step S8 is completed, it is next determined whether the full-press switch SW2 in the release section 11 is on / off. Step S
9). When the full-press switch SW2 is turned on, the diaphragm drive unit 18 narrows down the diaphragm mechanism to the set diaphragm value,
At the same time, the mirror is raised, and then the shutter drive unit 17
Then, the shutter is opened to give a proper exposure to the film, and then the shutter is closed to open the diaphragm and the mirror is down (step S10). Next, the shake correction lens 3 shifted in step S8 is reset to the original position (step S1
1), the process ends. In addition, in preparation for close-up of documents,
If necessary, an operator for prohibiting lens shift for the soft focus effect may be provided.

[0016]

According to the present invention, the shake correction is performed when the set shooting condition is a shooting condition that does not require shake correction by the shake correction unit and when shooting is performed at an upsize of a predetermined shooting magnification or more. Since the shake correction lens not used for is automatically shifted to the second position (the position beyond the shift area at the time of shake correction), the resulting aberration change is used to obtain an image having a soft focus effect. , The photographer can concentrate on framing and can provide a camera with a soft focus function which is inexpensive.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a single-lens reflex camera to which the present invention is applied.

FIG. 2 is a block diagram showing an embodiment of the present invention.

FIG. 3 is a flowchart showing a processing procedure of the present invention.

[Explanation of symbols]

 1 Camera Body 2 Interchangeable Lens 3 Shake Correction Lens 4 Shake Correction Actuator 10 System Control Section 11 Release Section 12 Exposure Factor Setting Section 13 Shake Detection Sensor 14 Photometry Section 15 Focal Length Detection Section 16 Distance Measurement Section 17 Shutter Drive Section 18 Aperture Drive unit 19 Exposure control unit

Claims (2)

[Claims] 1. A camera having shake correction means for preventing a shake by shifting a shake correction lens, wherein it is determined whether a set shooting condition is a shooting condition requiring shake correction by the shake correction means. And a second judging means for judging whether or not the set photographing magnification is larger than a predetermined magnification, the first judging means judges that the shake correction is unnecessary, and When the second determining means determines that the photographing magnification is larger than the predetermined magnification, the shake correcting means shifts the shake correction lens beyond the shift region for performing the shake correction, thereby providing a soft focus effect. A camera with a soft focus function, which is characterized by obtaining an image having 2. The soft focus according to claim 1, wherein the photographing condition that requires the shake correction to be judged by the first judging means is that the set shutter speed is equal to or longer than the handshake limit second. Camera with functions.