Piggyback | The easiest way to enter the realm of | |
| phy is via the piggyback method. Piggyback photography is done with a | |
| camera and its normal lens riding on top of the telescope. Through piggyback | |
| photography you can capture entire constellations and record large scale | |
| nebulae that are too big for prime focus photography. Because you are | |
| photographing with a low power lens and guiding with a high power telescope, | |
| the margin for error is very large. Small mistakes made while guiding the | |
| telescope will not show up on film. Use the optional piggyback mount to attach | |
| the camera to the telescope. | |
| As with any form of | |
| ing site. Light pollution around major urban areas washes out the faint light of | |
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| 1. | Polar align the telescope (using one of the methods described earlier) and |
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| start the clock drive. |
| 2. | Load your camera with slide film, ISO 100 or faster, or print film, ISO 400 |
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| or faster! |
| 3. | Set the f/ratio of your camera lens so that it is a half stop to one full stop |
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| down from completely open. |
| 4. | Set the shutter speed to the “B” setting and focus lens to infinity setting. |
| 5. | Locate the area of the sky that you want to photograph and move the |
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| telescope so that it points in that direction. |
| 6. | Find a suitable guide star in the telescope field. This is relatively easy |
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| since you can search a wide area without affecting the area covered by |
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| your camera lens. If you do not have an illuminated cross hair eyepiece for |
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| guiding, simply defocus your guide star until it fills most of the field of view. |
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| This makes it easy to detect any drift. |
| 7. | Release the shutter using a cable release. |
| 8. | Monitor your guide star for the duration of the exposure. Make all correc- |
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| tions using the hand controller. |
| 9. | Close the camera’s shutter. |
| As for lenses, get good ones that produce sharp images near the edge of the | |
| field. Generally, stay away from generic lenses. The lenses should have a | |
| resolving power of 40 lines per millimeter. A good focal length range is 35 to | |
| 100mm for lenses designed for 35mm cameras. | |
