undersampling reduces the influence of guiding errors and improves signal to noise at the expense of finest detail
oversampling will require a good mount and careful guiding. OK for high magnification solar, lunar or planetary imaging.
Might cause signal to noise issues with wide-field imaging
It is important to find a good balance between over- and undersampling. Namely so, that the camera still
works as sensitive as possible, but the images are good shaded. The following figure illustrates graphically
this relationship.
On the left the undersampling shows almost only square stars. On the right oversampling shows many shades of gray,
but the light of the stars is smeared over many pixels.
Center of the picture is an example of good sampling.
For deep sky imaging, the rule of thumb for the image scale is to achieve a value of about 1.5 arcsecs to 2 arcsecs per pixel.
In this rule of thumb, the normal local seeing should be included. The seeing value is simply divided by
2.67 (low) or 2 (high) if you have local seeing on average of 4 arcseconds.
Preview
Yellow rectangle = FoV of selected chhip
Red outline = Vignetting
Green outline = FoV of selected eyepiece on telescope
White circle = Apparent moon size
Seeing-Values
1 = FWHM 0-1 Dream
2 = FWHM 1-2 Perfect
3 = FWHM 2-3 Very good
4 = FWHM 3-4 Good
5 = FWHM 4-5 Average
6 = FWHM 5-6 Average
7 = FWHM 6-7 Moderate
8 = FWHM 7-8 Bad
9 = FWHM 8-9 Very bad
10 = FWHM 9-10 Unusable
Camera Rotation by 90 degrees
AstroVis_Guide Donationware
The software can still be used without restrictions, but the author would be happy to receive a donation
of any amount if you find the program useful. But also as compensation for the costs arising from the further development and hosting of the software.
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The graphic analysis and the calculation of key figures can therefore not be carried out.