The StellarMate Plus Manual
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· Increase binning to the maximum supported by your camera.
· Increase exposure time to 10 seconds or more.
· Enable Dark Frame option to clean up the image before sending it to the
solver.
· Perform rough Polar Alignment before using the alignment module.
· Automatic downsampling is turned on by default. It essentially reduces the
size of your image before it is fed to the solver. For most users, this option
improves solver efficiency. However, it can create issues for others. Go to
Astrometry options and turn off automatic downsampling and if that doesn't
work, try turning off downsampling completely.
Polar Alignment
Polar Alignment Assistant
When setting up a German Equatorial Mount (GEM) for imaging, a critical aspect
of capturing long-exposure images is to ensure proper polar alignment. A GEM
mount has two axis: Right Ascension (RA) axis and Declination (DE) axis. Ideally,
the RA axis should be aligned with the celestial sphere polar axis. A mount's job is
to track the star's motion around the sky, from the moment they rise at the
eastern horizon, all the way up across the median, and westward until they set.
Video Demo
In long exposure imaging, a camera is attached to the telescope where the image
sensor captures incoming photons from a particular area in the sky. The incident
photons have to strike the same photo-site over and over again if we are to
gather a clear and crisp image. Of course, actual photons do not behave in this
way: optics, atmosphere, seeing quality all scatter and refract photons in one way
or another. Furthermore, photons do not arrive uniformly but follow a Poisson
distribution. For point-like sources like stars, a point spread function describes
how photons are spatially distributed across the pixels. Nevertheless,
the overall idea we want to keep the source photons hitting the same pixels.
Otherwise, we might end up with an image plagued with various trail artifacts.
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