Quote:
Originally Posted by telecasterguru
Allan,
You look like you're getting there.
When you say you took your flats down to a mean of 24000ADU how did you measure that?
Frank
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Measured in Nebulosity using the pixel stats function - very usefull.
Quote:
Originally Posted by peter_4059
Nice shot Allan. Good to hear the flexure is coming under control again.
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Thanks Peter, I had visions of what you went through to get rid of focus creep or what ever. Really didnt want to go there.
Quote:
Originally Posted by gregbradley
Good result Allan.
I aim for about 20,000 ADU for flats. I read a report that said to go for more as it resulted in lower noise. I tried 50,000 ADU and the flats just completely wrecked the image and overwhelmed it. So not sure what went wrong there or if that approach only works with some setups.
Greg.
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Greg
Have to agree with you as I was having troubles with flat corrections leaving residue gradients that became worse and worse on stretching the image so I played around with various ADU levels (from 9000 - 50000) and found as you have thatat 20-24000 is optimum for my QHY8. After processing it then gives a very flat frame that doesn't have a gradient in it.