flat frames

Image processing, astrometry, photometry, etc.
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maplearn
Posts: 9
Joined: 11 Jan 2021, 06:02

flat frames

Post by maplearn » 16 Jan 2021, 05:54

Cannot fame any detailed instructions in the manual on flat frames. How long should the exposure be and how bright the image should be, is there a way to measure the brightness of the image?

Thanks,

Ernie

Iver
Posts: 55
Joined: 08 Jan 2019, 04:32

Re: flat frames

Post by Iver » 16 Jan 2021, 16:45

In the bottom left corner of your flat there are some numbers, B is the background average. For my 16 bit camera I try to get that value between 25,000 and 30,000. In that range my flats correct very well. For a 12 bit camera you will need a lower range. In the AstroArt help topics search for "Flat Field" for more info.
Iver

maplearn
Posts: 9
Joined: 11 Jan 2021, 06:02

Re: flat frames

Post by maplearn » 18 Jan 2021, 01:10

There are light and dark frame choices, for a flat frame I should just take a light image?

Ernie

Iver
Posts: 55
Joined: 08 Jan 2019, 04:32

Re: flat frames

Post by Iver » 18 Jan 2021, 04:14

The Dark Frame choice in the image tab closes the camera shutter if the camera has one.
Iver

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