Celestron OMNI XLT 102 manual Using Digital Cameras

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4.Set the shutter speed to the “B” setting and focus the lens to the infinity setting.

5.Locate the area of the sky that you want to photograph and move the telescope so that it points in that direction.

6.Find a suitable guide star in the telescope eyepiece field of view. This is relatively easy since you can search a wide area without affecting the area covered by your camera lens. If you do not have an illuminated cross hair eyepiece for guiding, simply defocus your guide star until it fills most of the field of view. 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 making the necessary corrections needed to keep the star centered.

Short Exposure Prime Focus Photography for Refractors & Newtonians

Short exposure prime focus photography is the best way to begin recording celestial objects. It is done with the SLR camera attached to the telescope without an eyepiece or camera lens in place. To attach your SLR camera you need the T-adapter and a T-Ring for your specific camera (i.e., Canon, Nikon, Pentax, etc.). The focuser for the refractors and Newtonian has a built-in T-adapter and is ready to accept a 35mm camera body. The T- Ring replaces the 35mm SLR camera’s normal lens. Prime focus photography allows you to capture the entire solar disk (if using the proper filter) as well as the entire lunar disk. To attach your camera to your telescope:

See note about digital cameras below.

1.Remove the eyepiece from the 1¼” eyepiece holder.

2.Unthread the 1¼” eyepiece holder from the focuser assembly. This will expose the male thread of the built- in T-adapter.

3.Thread the T-ring onto the exposed T-adapter threads.

4.Mount your camera body onto the T-Ring the same as you would any other lens.

Short Exposure Prime Focus Photography for Schmidt-Cassegrains

Use a T-Adapter (# 93633-A) which threads on to the back of the telescope. The T-Ring threads onto the T- Adapter and then mount your camera body onto the T-Ring like you would any other lens.

Using Digital Cameras

To attach a digital camera to your telescope you will need the Universal Digital Camera Adapter (# 93626). The adapter allows the camera to be mounted rigidly. You will follow your camera instructions for capturing images as the information below relates to 35mm SLR cameras.

With your camera attached to the telescope, you are ready for prime focus photography. Start with an easy object like the Moon. Here’s how to do it:

1.Load your camera with film that has a moderate-to-fast speed (i.e., ISO rating). Faster films are more desirable when the Moon is a crescent. When the Moon is near full, and at its brightest, slower films are more desirable. Here are some film recommendations:

•T-Max 100

•T-Max 400

•Any 100 to 400 ISO color slide film

•Fuji Super HG 400

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Contents Omni XLT Series Telescopes Table of Contents Astrophotography Page Omni XLT 102 Refractor Omni XLT 150 Newtonian Omni XLT 127 Schmidt-Cassegrain Setting up the Tripod Attaching the Equatorial Mount Installing the Counterweight Bar Attaching the Center Leg BraceInstalling the Counterweights Attaching the Slow Motion Control Knobs CablesAttaching the Telescope Tube to the Mount Installing the Finderscope Installing the Visual BackInstalling the Star Diagonal Installing the EyepiecesMoving the Telescope Manually Balancing the Mount in R.AAdjusting the Mount Balancing the Mount in DECAdjusting the Mount in Altitude Adjusting the Mount in AzimuthPage Page Focusing Image OrientationAligning the Finderscope Calculating MagnificationDetermining Field of View General Observing HintsCelestial Coordinate System Motion of the Stars Latitude Scale Pointing at PolarisFinding the North Celestial Pole Polar Alignment in the Southern Hemisphere Polar Alignment with the Latitude ScalePointing at Sigma Octantis Finding the South Celestial Pole SCPDeclination Drift Method of Polar Alignment Aligning the R.A. Setting Circle Using the R.A. Vernier Scale 11 Vernier ScaleObserving the Moon Lunar Observing HintsObserving the Planets Planetary Observing HintsObserving the Sun Solar Observing HintsObserving Deep Sky Objects Seeing ConditionsUsing the Lens Cap Aperture Stop with Refractor Telescopes SeeingPiggyback Photography Using Digital Cameras Eyepiece Projection for a Schmidt-Cassegrain FullLong Exposure Prime Focus Photography Planetary and Lunar Photography with Special Imagers CCD Imaging for Deep Sky Objects Terrestrial PhotographyMetering Reducing VibrationCare and Cleaning of the Optics Collimation of RefractorsCollimation of a Schmidt-Cassegrain Two 2 turnsCollimated telescope Should appear Symmetrical with Collimation of a Newtonian Aligning the Secondary MirrorBoth mirrors aligned with your eye looking into the focuser Night Time Star Collimating As a Series 1 # Page Page Appendix a Technical Specifications Appendix B Glossary of Terms Page Page Page Page Page Page Page Page Celestron Two Year Warranty
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