JP2007047623A - Photographic adapter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photographic adopter which is a photographic device to take photographs by connecting a telescope and a camera equipped with a zoom lens, that can simply adjust the displacement made by the entrance pupil positional fluctuations of the zoom lens between the exit pupil position of the telescopic and the entrance pupil position of the photographing optical system when zooming, to obtain uniform bright photographs without shading. <P>SOLUTION: The photographic adapter has a movable section for changing the positional relation between the telescope and the camera equipped with a zoom lens in the direction of the optical axis, an input section to input the focal length information of the zoom lens from the camera, and an output section to output the optimum positional information of the telescope and the camera, according to the focal length information inputted from the input section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an adapter for a photographing apparatus that couples a camera equipped with a zoom lens behind a telescope.

A telescope and a digital still camera are combined to magnify a subject in the distance, such as a wild bird magnified by a telescope, with a camera. Conventionally, in order to connect a telescope and a camera, various adapters for photographing devices that fix both to each other have been used. Such an adapter for a photographing device is, for example,
Is disclosed. When photographing with a camera connected behind the eyepiece of a telescope, if the exit pupil of the telescope and the entrance pupil of the camera are not substantially matched, the incident light flux will be generated by the camera aperture and the photographic lens itself. Vignetting causes the peripheral portion of the obtained photograph to become dark and the image quality to deteriorate. Therefore, it is important to determine the positional relationship between the eyepiece of the telescope and the camera in consideration of the pupil position of both optical systems.

  Most photographing optical systems installed in compact digital still cameras that are currently popular are zoom lenses with a zoom ratio of about 3 times. When such a digital still camera and a telescope are combined to perform magnified shooting, shooting of the exit pupil of the telescope optical system and the camera on the wide-angle side where the vignetting is most likely to occur due to the large angle of view and pupil displacement. Although the entrance pupils of the optical system are matched, if so-called zooming is performed and the focal length of the camera's imaging optical system is changed, the position of the entrance pupil of the imaging optical system changes, resulting in vignetting of the light flux and The part becomes dark.

However,
None of the conventional adapters for photographing devices disclosed in the above document have a mechanism for correcting the pupil position fluctuation as described above, and as a result of zooming, it is inconvenient because it cannot cope with vignetting. It was.

  The present invention has been made to solve the above-described conventional problems, and is an adapter for a photographing apparatus that couples a camera equipped with a zoom lens behind a telescope, and performs zooming with a zoom lens. However, it is an issue to provide an adapter for a photographic device that can obtain vignetting-free photos.

In order to achieve the above object, the photographing apparatus of the present invention has the following configuration.
An adapter for a photographing apparatus that couples a camera equipped with a zoom lens behind the telescope, the adapter comprising a movable part that changes a positional relationship in an optical axis direction between the telescope and the camera equipped with the zoom lens; A configuration having an input unit that inputs focal length information of the zoom lens from a camera, and an output unit that outputs optimal position information of the telescope and the camera according to the focal length information input from the input unit And

  By adopting the above configuration, we provide a camera adapter that combines a camera equipped with a zoom lens behind the telescope and can take vignetting-free pictures regardless of zooming. can do.

  Embodiments will be described below with reference to the accompanying drawings.

FIG. 1 is a configuration diagram of an embodiment according to the present invention.
The imaging device adapter 100 includes a support portion 3 having an L-shaped cross section and a movable portion 6 that can move on the support portion 3 in the optical axis direction. A telescope eyepiece 1 is detachably coupled to one end of the support 3, and the camera 2 is mounted on the movable unit 6 via a coupling component 5, and moves back and forth on the camera. . The coupling component 5 has a structure in which the camera can be adjusted vertically and horizontally so that the optical axis of the telescope optical system and the optical axis of the photographing optical system of the camera can be adjusted. The photographing optical system of the telescope eyepiece 1 and the camera 2 is connected by a bellows 4 in order to prevent stray light from the outside.

  The movable unit 6 includes a computer 7 having an input unit that inputs and outputs information, an output unit, and a control unit that controls the drive unit, a drive unit 10 that moves the movable unit 6, the telescope eyepiece unit 1 and the camera 2. A display unit 8 such as a liquid crystal monitor for displaying positional relationship information, and an information storage unit 11 for storing an optimum position of the telescope and camera used for photographing according to the focal length taken by the zoom lens are provided. . The computer 7 retrieves information on the change in focal length due to zooming of the photographing optical system (hereinafter referred to as zooming information) from the photographing information management unit 9 that manages photographing information of the camera body, and according to the focal length, The optimum positional relationship between the telescope eyepiece 1 and the camera 2 is determined from optimum position information (hereinafter referred to as optimum position information) corresponding to the focal length of the zoom lens stored in advance in the information storage unit 11. And the drive part 10 is controlled and the movable part 6 is driven so that the telescope eyepiece part 1 and the camera 2 may become an optimal position. The optimum position of the telescope and the camera is a position where the exit pupil position of the telescope and the entrance pupil position of the zoom lens substantially coincide. The optimum position information is calculated in advance from the exit pupil position of the telescope used for photographing and the change information of the entrance pupil position accompanying zooming of the zoom lens mounted on the camera, and is stored in the information storage unit 11. . At this time, the information stored in the information storage unit may be a method of reading the information stored in the card or the like. If the card or the like is stored in advance for a plurality of combinations of a telescope and a camera equipped with a zoom lens used for shooting, it can be used for a plurality of combinations of telescopes and cameras of different models. Is more efficient. Needless to say, the optimum position information may be directly input to the computer 7. The drive unit 10 may be controlled manually according to the output from the output unit of the computer 7, or the drive unit is controlled by the control unit of the computer 7 by using a stepping motor or the like to be electrically driven. The movable part 6 may be moved automatically.

  If the display unit 8 displays that the positional relationship between the telescopic eyepiece unit 1 and the camera 2 is the optimum positional relationship determined by the computer 7, the telescopic eyepiece unit 1 and the camera 2 can be connected to each other. It is easy to confirm that the positional relationship is in an optimal state, and it is convenient to prevent shooting with an inappropriate positional relationship. The indication of the optimal positional relationship is a numerical value indicating the positional relationship, such as turning on the lamp when in the optimal position, displaying a circle when appropriate, or displaying a cross when inappropriate. However, various methods are conceivable, such as displaying the suitability by changing the color of the characters. In the present embodiment, the camera 2 is coupled to the movable portion 6 to move the camera, but it goes without saying that the member to which the telescope is coupled may be configured to be movable. In addition, the computer 7, the display unit 8, and the information storage unit 11 are configured to be attached to the movable unit 6 in the present embodiment, but may be configured to be attached to the support unit 3.

Next, an example of how the vignetting of the light beam is improved by using the present invention will be described.
FIG. 2 illustrates a state in which light rays are vignetted due to a difference in distance between the eyepiece optical system 12 of the telescope and the photographing optical system 13 of the camera.

  FIG. 2A shows a case where the exit pupil position 17 of the telescope optical system and the entrance pupil of the photographing optical system 13 of the camera coincide with each other on the wide angle side, and exits from the image 18 by the telescope objective lens and exits from the eyepiece 14. The light beam exits the camera taking lens 15 and then passes through the middle of the camera aperture 16 without any vignetting. However, as shown in FIG. 2B, when the distance between the eyepiece optical system 12 and the photographing optical system 13 of the camera is not appropriate, the light is blocked by the diaphragm 16 of the camera, and the periphery of the screen becomes dark. Fig. 3 shows the above-mentioned vignetting as an example of a zoom lens that includes an angle of view corresponding to a focal length of 35 mm in terms of 35 mm format, and the periphery of the screen when zooming from the wide-angle side to the telephoto side. It is an example of a partial light quantity change. According to FIG. 3, when zooming is performed and the angle of view is changed, it can be seen that the peripheral luminous flux is vignetted and the amount of light decreases particularly near the wide-angle side.

  In order to avoid such a state, as shown in FIG. 2C, the vignetting caused by the diaphragm 16 of the camera can be eliminated by bringing the photographing optical system 13 of the camera close to the eyepiece optical system 12 of the telescope. That is, the optimum distance between the eyepiece optical system 12 of the telescope and the photographing optical system 13 of the camera corresponding to the focal length of the zoom lens corresponding to FIG. 2B is calculated and stored in advance, and the focal length corresponding to FIG. When the zoom lens is moved, the movable part 4 of the photographing apparatus is moved so as to avoid the vignetting so that the state shown in FIG. 2C is obtained.

  Fig. 4 shows the change in the amount of light at the periphery of the screen when zooming from the wide-angle side to the telephoto side when the present invention is applied. It can be seen that a good image without vignetting can be obtained.

Configuration diagram of an embodiment according to the present invention Illustration of vignetting The figure which shows the example of a screen peripheral part light amount change when there is vignetting The figure showing an example of a screen peripheral part light amount change at the time of zooming from the wide-angle side to a telephoto side at the time of applying this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Eyepiece part of telescope 2 Camera 3 Support part of imaging device adapter 4 Bellows 5 Coupling part of camera and imaging device 6 Movable part of imaging device adapter 7 Computer 8 Display part 9 Camera imaging information management part 10 Drive part 11 Information storage unit 12 Telescope eyepiece optical system 13 Camera photographing optical system 14 Eyepiece lens 15 Camera photographing lens 16 Camera aperture 17 Exit pupil position of telescope optical system 18 Image of observation object by telescope objective lens 19 Camera image plane

Claims (4)

An adapter for a photographing apparatus that couples a camera equipped with a zoom lens behind a telescope, wherein the adapter includes a movable part that changes a positional relationship in an optical axis direction between the telescope and the camera equipped with the zoom lens. An input unit that inputs focal length information of the zoom lens from a camera, and an output unit that outputs optimal position information of the telescope and the camera according to the focal length information input from the input unit. Featured adapter for photographic equipment. The adapter for the photographing apparatus includes an information storage unit that stores optimum position information of the telescope and the camera according to a focal length taken by a zoom lens attached to the camera. The adapter for an imaging device according to 1. The imaging device adapter according to claim 1, wherein the imaging device adapter includes a drive unit that drives the movable unit and a control unit that controls the drive unit. The said imaging device adapter has a display part which displays that the positional relationship of the said telescope and the said camera exists in the optimal position, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Adapter for photography equipment.