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Old 16-03-2020, 08:44 AM
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multiweb (Marc)
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Join Date: Oct 2007
Location: Sydney
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Quote:
Originally Posted by Merlin66 View Post
Marc,
""but dust motes will still show if you don't have the right levels in your flats""

I'm using mono cameras and get the histogram up around 85% when imaging these flats.
Is this what you mean? (I assume levels may apply to OSC?)
Mono or bayer doesn't make any difference. What I mean is that if you have a dark dust donut and flatfield it with the wrong flat it might still show as a dark(er) blob or lighter spot in your calibrated sub.

Are you trying to flat field primarily to get rid of specs and dust, but not worrying too much about uneven illumination? I'll dig some flats from various scopes I still have on file to show what I mean.

The sharp small specs on the sensor, just wipe them out and be done with it. The bigger ones, well they can be anywhere on correctors, filters, optics but they're easier to get rid off with flat fielding. The little ones close to the imaging planes are the pesky ones to process out IMHO. Easier to wipe.
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