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It is always necessary to make flat frames, they correct uneven illumination on the chip and calibrate out any dust particles in the imaging train. Darks are optional, the Sony Atik cameras are very clean, so many don't use darks. If you're not doing darks then just make bias calibration frame. If you do use darks, the bias is contained within the dark frame.

My advice is try with and without and see what works best for you.

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I agree. I would certainly take bias because you will need these as darks for your flats. (If you don't subtract a dark from your flats they will probably over-correct. However, there is no need to take dedicated darks for flats because, at the short exposures in question, there will be no difference between dedicated darks and a master bias.) If your stacking software supports bad pixel mapping then that's an option. I stack in AstroArt and use a master bias as a dark and a Defect Map (AKA bad pixel map.) It works like a charm. Even just subtracting a master bias instead of a master dark might be the easiest solution on a Sony.

Enjoy the camera. It's good!

Olly

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8 minutes ago, Astroboy239 said:

One can take flats without a light pannel on ccd which are illuminated right? Well Im not sure. 

Varad 

 

Flats simply require an even ('flat') light source right across the objective with everythng else, including the focus position, left just as it was for the imaging run. You can use a panel, you can put a white T shirt over the objective and use the sky, you can do them in twilight provided you dither to remove any faint stars appearing, you can use the inside of your observatory if you have one that's plain and featureless...

Olly

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53 minutes ago, Astroboy239 said:

OK... What's the use of the ccd illumination then? 

Varad 

Are you referring to front/back illuminated ccd's?  If so this just describes how they are manufactured, they don't actually have any light emitting parts.

 

I use my iPad and a t-shirt for my flats, seems to work fine.

 

Certainly the benefit of darks is far less on a low noise cooled CCD, a bad pixel map seems to work just as well and is a lot less processor intensive.

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