JPH0933823A - Photographing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a telephotographing system by which a camera for photographing is easily attached and further delicate focusing is performed in an optical system capable of observing a far substance with a naked eye such as an astronomical/terrestrial telescope. SOLUTION: In this photographing system, an ocular optical system and a camera body 51 are selectively attached to/detached from an adapter lens barrel 41 attached to freely move along an optical axis in a lens barrel main body 13 holding an objective lens group L1; the camera body 51 is constituted to be attached to the lens barrel 41 through a lens mount 53 and any extended lens barrel 55 having different focal length and variable power ratio, and the lens barrel 41 need not be positionally adjusted even in the case the lens barrel 55 is changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photography system that enables an astronomical telescope or a terrestrial telescope to be used as a photographing lens of a camera.

[0002]

2. Description of the Related Art The optical system of a conventional refracting astronomical telescope generally includes an objective optical system, a field optical system and an eyepiece optical system. When taking a picture with this astronomical telescope, it was common to remove the eyepiece optical system and attach the body of the single-lens reflex camera through the camera adapter. The conventional example is shown in FIG. The objective optical system and the field optical system are usually fixed to the lens barrel body 101, and the eyepiece optical system (not shown) is the lens barrel body 10 (not shown).
It is attached to the rear end portion of the movable lens barrel 103 which can move forward and backward along the optical axis with respect to 1. The movable lens barrel 103 includes a rack and pinion mechanism 105 (a rack 105a and an operation knob 1).
05b only) is supported by the lens barrel body 101 by
It moved along the optical axis to fulfill the focus adjustment function.

When this astronomical telescope is used as a telephoto lens of a camera, the eyepiece optical system is removed from the movable lens barrel 103, and instead, the single lens reflex camera body 51 is mounted via the camera adapter 111. Since back focus adjustment is necessary when the camera body 51 is mounted, the rack and pinion mechanism 105 is operated to move the movable lens barrel 103, that is, the camera body 51 back and forth to adjust the focus. However, since the rack and pinion mechanism 105 is difficult to finely adjust, it is not suitable for focus adjustment of the camera.

Further, in the prior art, for example, in order to carry out a reduced image, as shown in FIG. 6, an extension lens barrel 113 having a reduction optical system L21 is prepared, and the movable lens barrel 103 is moved to the shortest state and moved. The extension lens barrel 113 must be attached to the lens barrel 103, and the camera body 61 must be attached via the camera adapter 111.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and provides a photography system in which an astronomical object / terrestrial telescope or the like can be easily used for photography.
With the goal. It is another object of the present invention to provide a photographic system in which an astronomical / terrestrial telescope or the like can be easily used as a photographic lens having different focal lengths.

[0006]

SUMMARY OF THE INVENTION The present invention, which achieves the above object, is a photographic system for taking a picture by mounting a camera on a movable lens barrel which is movably connected to and supported by a lens barrel body of a telescope along an optical axis. A camera mounting lens barrel for detachably mounting a camera on the movable lens barrel, wherein even if two or more camera mounting lens barrels having different magnifications are exchanged, the image plane position with respect to the mounted camera is Formed so as not to move,
It has features.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a side view showing an essential part of an embodiment of the present invention by cutting an upper half from an optical axis, and FIGS. 2 to 4 are partially longitudinal side views showing an embodiment of the present invention. is there.

The astronomical telescope 11 has a lens barrel body 13,
The objective lens group L1 is fixed to the front end of the lens barrel body 13, and the field lens group L2 is fixed to the rear end thereof. An eyepiece lens (eyepiece optical system, eyepiece) (not shown) and an adapter lens barrel (moving lens barrel) 41 for mounting the camera body 51 for taking a photograph are further mounted on the rear end of the lens barrel body 13. ing.

The adapter lens barrel 41 is inserted into the lens barrel body 13 from the rear end portion thereof, and is supported by a helicoid mechanism so as to be able to move straight forward and backward without rotating along the optical axis. At the rear end portion of the adapter barrel 41, an eyepiece lens and a mount portion 42 for mounting the camera body 51 are formed. The camera body 51 is attached to the adapter lens barrel 41 via a camera mounting lens barrel.

The structures of the helicoid mechanism and the adapter barrel 41 will be described in more detail with reference to FIG. A fixing ring 21 is fixed to the rear end of the lens barrel body 13. The fixing ring 21 has a tip portion inside the lens barrel body 13,
The field lens barrel 23 is fixed. A field lens L2 is supported by the field lens barrel 23 via a field lens support frame 24.

Further, a helicoid ring 31 is inserted into the fixed ring 21 from the rear end side. The front end of the helicoid ring 31 abuts on the front stage part 21a formed on the inner peripheral surface of the fixing ring 21, and the flange part 32 protruding from the outer peripheral surface of the rear part is formed on the rear end surface of the fixing ring 21. ,
The forward movement is blocked by contacting the rear stage portion 21b. Then, the flange portion 32 is fixed to the rear stage portion 21b by the annular retaining plate 24 screwed to the rear end portion of the fixing ring 21.
It is supported by being sandwiched between and. As a result, the helicoid ring 31 has the tip outer peripheral surface and the flange portion 32.
By the outer peripheral surface in the vicinity slidingly contacting the inner peripheral surface of the fixed ring 21, it is rotatably supported without moving in the direction along the optical axis.

An inner helicoid 33 is formed on the inner circumference of the tip of the helicoid ring 31. Of the helicoid ring 31,
The operation ring 34 is fitted and fixed to a portion protruding from the rear end of the fixing ring 21 to the outside. The operation ring 34 is an operation ring for an observer or a photographer to grip and rotate with an hand, and a non-slip mark is formed on the outer peripheral surface thereof.

An adapter mounting cylinder (moving cylinder) 41 is inserted into the helicoid ring 31 from the rear end side. In the adapter mounting cylinder 41, an outer helicoid 43 formed on the outer peripheral surface of the tip portion is screwed into the inner helicoid 33 of the helicoid ring 31. The adapter mounting cylinder 41 includes a helicoid 43.
At least 1 extending in parallel with the optical axis by cutting out a part of
A book straight guide groove 44 is formed. A tip end portion of a guide pin 25 which is screwed into the fixing ring 21 and extends toward the optical axis is fitted into the straight guide groove 44, and guides the adapter mounting cylinder 41 movably along the optical axis without rotating. ing. The straight guide groove 44 may pass through the adapter mounting cylinder 41, or may be provided in a portion not having the helicoid 43.

The straight guide groove 44 and the guide pin 2
5 and the helicoids 33 and 43 constitute a helicoid mechanism. That is, when the helicoid ring 31 rotates, the adapter mounting cylinder 41 moves back and forth along the straight guide groove 44 according to the leads of the helicoids 33 and 43. Reference numeral 26 is a set screw for fixing the adapter mounting cylinder 41 at a predetermined position.

Next, a usage state of the illustrated embodiment will be described with reference to FIGS. 2 to 4. These are a form in which a mount adapter and an extension lens barrel are used as a camera mounting lens barrel for mounting a camera on an astronomical telescope. FIG. 2 shows an example in which an extension lens barrel 55 and a mount adapter 53 are used for taking an image without changing the focal length of the astronomical telescope 11.

In order to mount the camera body 51, first, the adapter mounting barrel 41 is pulled into the lens barrel body 13 and the operation ring 34 is rotated so as to be in the shortest state. Then, the extension lens barrel 55 is attached to the adapter attachment barrel 41, the mount adapter 53 is attached to the extension lens barrel 55, and the camera body 51 is attached to the mount adapter 53. With the above work, the mounting of the camera body 51 is completed. Extension barrel 5
5, the mounting order of the mount adapter 53 and the camera 51,
The order in which the adapter mounting cylinder 41 is placed in the shortest state is arbitrary.

Focus adjustment is performed by rotating the operation ring 34. When the photographer rotates the operation ring 34, the adapter mounting cylinder 41 moves back and forth with respect to the lens barrel body 13 by the helicoid mechanism, and moves the camera body 51 toward and away from the objective lens group L1 and the field lens group L2. . By moving the camera body 51 back and forth, the camera body 5
The film in 1 can be matched with the image plane of the objective lens group L1 and the field lens group L2, that is, focus adjustment can be performed.

FIG. 3 shows an embodiment using a reduction extension lens barrel 57 in place of the extension lens barrel 55, and FIG. 4 shows an embodiment using an enlargement extension lens barrel 59. is there.
The extension lens barrel 57 for reduction is equipped with a reduction optical system L3 for increasing the focal length of the telescope by 0.7, and the extension lens barrel 59 for expansion is an enlargement optical system for increasing the focal length of the telescope by 1.4 (an optical system having negative power). ) L4 is provided. These extension lens barrels 57,
With 59, the focal length of the telescope 11 is
Increase 0.7 times or 1.4 times. Moreover, the extension lens barrel 57, 5
The lens barrel 9 has a lens barrel length or focal length set so that the image plane does not move even after replacement. That is, once the focus adjustment operation is performed, it is not necessary to readjust the focus even if the extension lens barrel is replaced. Furthermore, the shooting screen range is set to, for example, 45 mm or more so that the shooting screen is not lost.

As is clear from the above description, in this embodiment, the adapter mounting cylinder 41 for mounting the camera body 51 is mounted.
Is attached to the lens barrel main body 13 via the helicoid mechanism, it is possible to perform delicate focus adjustment when taking a picture with the camera body 51 without providing a focus adjusting mechanism in the adapter. Although the present invention has been described above with reference to the drawings, it goes without saying that the present invention can also be applied to astronomical telescopes, terrestrial telescopes, and the like other than the illustrated telescope.

[0020]

As is clear from the above description, the present invention
In a photography system for taking a picture by mounting a camera on a movable lens barrel which is movably connected to an optical axis of a telescope's lens barrel body, the camera is attached to the movable lens barrel so that the camera can be detachably attached. Since two or more camera mounting lens barrels having different magnifications are formed so as not to move the image plane position with respect to the mounted cameras, There is no need to readjust the focus even if it is replaced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment in which the present invention is applied to an astronomical telescope, in which an essential part is cut in an upper half along an optical axis.

FIG. 2 is a side view showing an embodiment in which the present invention is applied to an astronomical telescope, with the upper half cut from the optical axis.

FIG. 3 is a side view showing another usage example of one embodiment in which the present invention is applied to an astronomical telescope, with the upper half cut from the optical axis.

FIG. 4 is a side view showing still another usage example of one mode in which the present invention is applied to an astronomical telescope, with the upper half cut from the optical axis.

FIG. 5 is a side view showing a form in which a camera is attached to a conventional astronomical telescope.

FIG. 6 is a side view showing another mode of mounting a camera on a conventional astronomical telescope.

[Explanation of symbols]

 11 Telescope 13 Lens barrel body 21 Fixing ring 25 Guide pin 26 Fixing screw 31 Helicoid ring 33 Inner helicoid 34 Operating ring 41 Adapter lens barrel 43 Outer helicoid 44 Straight guide groove 51 Camera body 53 Mount adapter 55 Standard extension lens barrel 57 For reduction Extension lens barrel 59 Extension lens barrel for enlargement

Claims (8)

[Claims] 1. A camera-equipped lens barrel for detachably mounting a camera on a movable lens barrel that is movably supported along an optical axis with respect to a lens barrel body of a telescope, the lens barrel having different magnifications. More than one camera mounting lens barrel,
A photography system characterized by being formed so that the image plane position with respect to the mounted camera does not move even if it is exchanged. 2. The extension lens barrel according to claim 1, wherein the camera attachment barrel includes an extension barrel attached to the movable barrel and a mount adapter for attaching a camera to the extension barrel. A photography system characterized by having a built-in double optical system. 3. The photography system according to claim 1, wherein the camera mounting lens barrel is mounted on the lens barrel main body via a helicoid mechanism. 4. The photography system according to claim 2, wherein the extension lens barrel includes a variable power optical system. 5. The photography system according to claim 2, wherein a plurality of extension barrels having different magnifications including reduction magnifications are prepared, and these are used alternatively. . 6. The helicoid mechanism according to claim 3, wherein the helicoid mechanism is formed in the movable lens barrel and a helicoid cylinder having an inner helicoid that is rotatably supported by the lens barrel body without moving back and forth. An outer helicoid screwed with an inner helicoid of the cylinder, a guide groove extending along an optical axis formed in the movable lens barrel, and provided in the lens barrel body,
A guide pin slidably fitted in the guide groove, and moving the movable lens barrel forward and backward without rotating;
A photography system characterized by. 7. The photography system according to claim 6, wherein the helicoid cylinder has an operation ring protruding from the rear end of the lens barrel body and fitted and fixed to the protruding portion. . 8. A photography system for taking a picture by mounting a camera on a telescope, wherein a transfer barrel supported movably along an optical axis with respect to the body of the telescope; And an adapter for attaching a camera to the extension lens barrel; and an extension lens barrel internally provided with an optical system having a negative power; and a photography system.