Meade LX200 R instruction manual Photography, LX200R with #62, Example of vignetting

Models: LX200 R

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Fig. 21: LX200R with #62

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Fig. 21: LX200R with #62

T-Adapter: (1) camera adapter, (2) T- mount, (3) camera body.

Fig. 22: Example of vignetting.

PHOTOGRAPHY

You may perform through-the-telescope photography with any 35mm camera body with a removable lens. You may connect a camera to a #62 T-Adapter which is then con- nected to the microfocuser assembly. See Fig. 21. Using this method, the telescope effectively becomes the lens of the camera.

The #62 T-Adapter (1, Fig. 21) connects to the microfocuser assembly, followed by a T-Mount (2, Fig. 21) for the particular brand of 35mm camera being used, followed by the camera body (3, Fig. 21).

To orient an object in the viewfinder of the 35mm camera body, use a small jeweler’s screwdriver to slightly loosen three adjustment screws around the outer knurled ring of the T-Mount. Rotate the camera body to achieve proper orientation of the object; then re-tighten the adjustment screws.

The #62 T-Adapter permits close-coupling of a camera body to the telescope. In this format vignetting occurs: The photographic image appears on film with a slight dark- ening (vignetting) at the corners of the 35mm frame (Fig. 22).

Photography through a long lens such as the LX200R requires special technique for good results, and the photographer should probably expect to waste a roll or two of film in acquiring this technique. Long-lens photography has its own rewards, howev- er, rewards that short-focus lenses cannot duplicate.

A few tips on photography with the LX200R telescopes:

1.Use the Field Tripod for the telescope. At an effective focal length of 2000mm, even small external vibrations can easily ruin an otherwise good photo.

For best results in photographing celestial objects, a wedge and One-Star polar alignment is recommended. See APPENDIX A, pages 50 through 54.

Caution: With the #62 T-Adapter and a camera body mounted to the LX200R photo port, the telescope can only be rotated vertically about 45°. Moving past this point may damage the telescope and camera.

2.Use a cable-operated shutter release. Touching the camera body to initiate shutter operation almost certainly introduces undesirable vibrations.

3.Focus the image with extreme care. While observing the subject through

the camera’s reflex viewfinder, turn the telescope’s focus knob (6, Fig. 1) to achieve the sharpest possible focus. Note that some 35mm cameras may have an optional focusing screen (available from the manufacturer) for use with a long telephoto lens. This screen provides a brighter and clearer image to focus, and is highly recommended.

4.Correct shutter speeds vary widely, depending on lighting conditions and film used. Trial-and-error is the best way to determine proper shutter speed in any given application.

Note: The camera used with your telescope may have an exposure meter that is still active when the standard lens is removed and the body is con- nected to the telescope with the T-Mount. If used for terrestrial photogra- phy, the camera meter should be acceptable. If used for astrophotography, the meter probably will not provide good results since camera meters are not made to compensate for a dark sky.

5.Terrestrial photography through the LX200R is sensitive to heat waves rising from the Earth’s surface. Long distance photography is best accomplished in the early morning hours before the Earth has had time to build up heat.

6.Photography of the Moon and planets through the LX200R can be especially grat- ifying, but points 1 through 4 should be particularly noted in this case. If you wish to take photographs using polar alignment, see APPENDIX A, page 52.

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Looking at or near the Sun will cause irreversible damage to your eye. Do not point this telescope

 

at or near the Sun. Do not look through the telescope as it is moving.

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Meade LX200 R instruction manual Photography, LX200R with #62, Example of vignetting