select the best frames to combine for best results and can also reject the poor- est frames.
Use the digital zoom feature to aid in focusing.
First zoom in on the target, focus, then zoom back out.
Refocus often throughout your imaging session. This ensures at least some of your images will have an excellent focus. It is also not uncommon for telescope movements to alter the focus slightly, so be sure to refocus for any new astro- imaging targets.
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 (movement of molecules in the air, such as heat rising) and poor transparency (moisture, 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 seeing and transparency 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 cannot. Keep these factors in mind when choosing an observing site for astronomical imaging.
For the best
Using Focal Reducers and Barlow Lenses
Focal reducers serve to decrease the focal length of your telescope. This increas- es the field of view seen by the camera (decreases camera magnification). This can be useful for obtaining images of wider objects, such as the full Moon or a landscape vista.
Barlow lenses, or other
For best planetary imaging, you should shoot with an effective focal ratio (tele- scope focal length ÷ telescope aperture) of f/20 or greater. This will give you a good combination of image brightness and image scale for planets. For most telescopes, a Barlow lens will be required to obtain this focal ratio. For example,
however. Experimentation will be needed to see what your telescope is capable of in the seeing conditions on a given night. If the image appears somewhat dim and fuzzy on the computer screen, you may want to consider removing the Barlow lens.
(Focal Reducers and Barlow lenses available through Orion, check the catalog or OrionTelescopes.com for more information).
Solar Filter
Warning: Always use a full aperture solar filter when viewing the sun.
With a properly fitting
(Solar filters available through Orion, check the catalog or OrionTelescopes.com for more information).
Flip Mirror
As easy as flipping a switch, the Imaging Flip Mirror enables the
Care and Maintenance
When the SSHD is not in use, remove the nosepiece then attach the dust cap. This prevents dust from accumulating on the SSHD’s optical window. The opti- cal window should only be cleaned if significant dust builds up for if the window is touched. Any quality optical lens cleaning tissue and optical lens cleaning fluid specifically designed for
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