5.If the star drifts north, the telescope mount is pointing too far west. If the star drifts south, the telescope mount is pointing too far east. Determine which way the star drifted and make the appropriate correction to the azi- muth position of the mount. Rotate the entire mount (and tripod) slightly east or west as needed or use the azimuth adjustment knobs (if your mount has them) to make fine adjustments to the mount’s position.
6.Next, point the telescope at a bright star near the eastern horizon and near the celestial equator (Dec. = 0).
7.Let the telescope track for at least five minutes, and the star should begin to drift north or south.
8.If the star drifts south, the telescope mount is pointed too low. If the star drifts north the telescope mount is pointed too high. Observe the drift and make the appropriate correction to the mount’s altitude (or latitude); most mounts have some sort of fine adjustment for this.
Repeat the entire procedure until the star does not drift significantly north or south in the eyepiece. When this is accomplished, you are very accurately polar aligned, and should be able to produce good (unguided) images of up to several minutes long, assuming the mount’s drives track well with little periodic error.
Choosing a Site for Astro-imaging
Once you have a focused image, you may find your image shifting and washed out. This can be caused by many environmental factors. Poor seeing (move- ment of molecules in the air, such as heat rising) and poor transparency (mois- ture, smoke, or other sky contaminants) will all serve to reduce image quality. That is why most major astronomical telescopes are on high mountains in thin air, to get above much of the transparency and seeing problems. Also, wind will move your telescope and affect images. Your eyes viewing through an eyepiece can change slightly to compensate for disturbances like these, but the camera can not. Keep these factors in mind when choosing an observing site for astronomical imaging.
For the best
Using Focal Reducers and Barlow Lenses
Focal reducers and barlow lenses change the effective focal length of a tele- scope. These lenses are inserted between the camera and telescope when imaging to change image scale.
Focal reducers serve to decrease the focal length of your telescope. This increases the field of view seen by the camera (decreases camera magnifi- cation). This can be very useful for obtaining images of
objects, such as the Andromeda Galaxy or the Pleadies star cluster. Focal reducers will usually thread onto the nosepiece of the StarShoot Pro.
Barlow lenses increase the focal length of your telescope, which makes the camera’s field of view narrower (increases camera magnification). This is use- ful for planetary imaging. Keep in mind that when the focal length is doubled, the image will become four times dimmer, so a longer exposure may be nec- essary. Barlow lenses are generally inserted in the focuser’s drawtube and secured with the thumbscrew on the focuser’s drawtube, and the StarShoot Pro’s nosepiece is inserted into the barlow and secured with the thumbscrew on the barlow lens.
Filters
Any standard Orion 2" filter will thread into the 2" nosepiece of the StarShoot Pro. Light pollution filters, or special light pollution filters designed for imaging (such as the Orion SkyGlow Imaging Filter) improves image contrast from urban areas with severe light pollution.
USB Extension Cable
Most imaging setups may require extra distance to comfortably reach from StarShoot Pro to the computer. We recommend purchasing a 10' USB exten- sion cable if you need more cord length (available through Orion, check the catalog and/or www.OrionTelescopes.com).
Care and Maintenance
When the StarShoot Pro is not in use, the dust cap should be replaced on the end of the nosepiece. This prevents dust from accumulating on the StarShoot Pro’s optical window. If significant dust does accumulate on the optical win- dow, or the optical surface is touched, then it should be cleaned.
Any quality optical lens cleaning tissue and optical lens cleaning fluid specifi- cally designed for
Before cleaning with fluid and tissue, blow any loose particles off the surface with a blower bulb or compressed air. Then apply some cleaning fluid to a tis- sue, never directly on the optics. Wipe the optical surface gently in a circular motion, then remove any excess fluid with a fresh lens tissue. Oily fingerprints and smudges may be removed using this method. Use caution; rubbing too hard may cause scratches.
Store the StarShoot Pro in the included hard carrying case. Keep the camera in a dry location away from direct sunlight.
40 | 41 |