Orion STAR SHOOT 52175 - Manual (Page 8)

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Planets such as Jupiter and Venus are bright and will require short
exposures.
For lower light planets such as Saturn the Auto White Balance should be dis-
abled by un-checking the auto box and the Red, Green & Blue Gain values
adjusted to a higher setting as well as using longer exposure times (or auto
exposure).
Select Video Capture Filter from AmCap (Windows)
or
WebCam List  settings  SN9C201 (Mac OS X) in order to access Auto
White and exposure settings.
Tips
Focusing
One of the hardest things to do in planetary imaging is achieving good focus.
You can make this process easier by simply watching the Live Video window
to focus. Depending upon the viewing conditions you may notice that the
image goes in and out of focus, this is due to viewing conditions. This is
to be expected and one of the reasons why post processing software can
bring out the best in your captured images. Focus as best as possible with
the average frame being at best focus to ensure more in focus frames than
out of focus. Image processing software can then be used to select the best
frames to combine for best results and can also reject the poorest frames.
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 astro-images, we recommend finding a location with dry air,
some altitude, and away from city or streetlights. Even a nearby hilltop in
the countryside can provide better viewing conditions than many convenient
backyard locations.
Loss of Camera Connection
If the computer connection to the camera is interrupted, you will need to
re-establish connection. This can happen due to several reasons; if a cable
becomes unplugged, the computer “freezes”, or the software/hardware
otherwise temporarily loses the data coming from the camera.
To re-establish camera connection, first close the Orion AmCap (Windows) or
WebCam Monitor (Mac OS X) program on your computer. Then, unplug and
re-plug the camera into the computer’s USB port. Now, open Orion AmCap
(Windows) or WebCam Monitor (Mac OS X), and the Live Video Window
should appear indicating re-established connection between camera and
computer.
Using Focal Reducers and Barlow Lenses
Focal reducers serve to decrease the focal length of your telescope.
This increases 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 tele-extenders, increase the focal length of your
telescope, which makes the camera field of view narrower (increases camera
magnification). This is useful for high-power planetary images. Keep in mind
that when the focal length is doubled, the image will become four times
dimmer, so a longer exposure may be necessary.
For best planetary imaging, you should shoot with an effective focal ratio
(telescope 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, Schmidt-Cassegrain telescopes usually have a focal ratio of
F/10. A 2x Barlow lens doubles the effective focal length of the telescope,
which makes the focal ratio f/20. Similarly, a 3x Barlow lens will yield of focal
ratio of F/30. You can also try using multiple Barlows to obtain even greater
effective focal ratios. There is a limit to how large a focal ratio your telescope
and seeing conditions can handle, 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).
Filters
For some types of planetary imaging, you may want to use color filters to
bring out subtle details. Any standard Orion 1.25" filter will thread into the
front of the SSSSI-IV’s barrel. Try using different color filters on a planet to
see which filters help best show planetary details.