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Nov 20, 2018 09:42:37   #
selmslie Loc: Fernandina Beach, FL, USA
 
gunflint wrote:
... "You can't get there from here."

To be more specific, if you zoom in on any of the stars you will see that they are spread out over several pixels.

Stars are point sources. With a perfect lens, a short enough exposure and no interference from the atmosphere (twinkling), the light from a star might fall within a single pixel. But all of those factors are working against us.

In addition, even if the star's light struck a single pixel, the Bayer array will use that (red or green or blue) information to create four adjacent RGB pixels, spreading the light out despite our best efforts. That is going to reduce the apparent brightness of the star by about 50%.

The brightest spot is spread over several pixels due to movement. Zoom in to 400% and its brightest pixel does not reach a value of 200 on a scale of 0-255.

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Nov 23, 2018 21:33:13   #
Robert M Loc: Clifton, NJ
 
Thank you for this information.....very helpful!

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