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Multiple Night Imaging & Calibration Files

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3 replies to this topic

#1 Muppy

Muppy

    Sputnik

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Posted 29 November 2021 - 02:55 AM

Greetings to All.

I am imaging the Andromeda Galaxy over a number of nights, hoping to get 10-12 hours of data.

I have taken darks, flats and bias calibration frames on the first night.

Do I have to retake all these calibration frames on the subsequent nights, or need I only take the darks and use the same flats and bias frames from the first night, when processing the complete data?

I will be using Pixinsight for the post-processing.

 

Thanks in advance for any assistance/advise.

Regards and clear nights!!



#2 Tapio

Tapio

    Fly Me to the Moon

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Posted 29 November 2021 - 03:09 AM

You don't have to take flats if your camera and optics are connected between sessions (ie no rotation or focus change).

You need to take darks if you have a DSLR and temperature changes between sessions.

If you have cooled camera with fixed temperature then no need for new darks.

No need for newer bias.


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#3 Muppy

Muppy

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Posted 30 November 2021 - 08:56 AM

Thanks for the clarification Tapio, much obliged.

Regards and do keep well …



#4 radon199

radon199

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Posted 30 November 2021 - 12:24 PM

While you don't have to take flats for each session, I would say it is recommended. You might not have flex in your imaging train, but dust could be moving in each session and you may end up with uncorrected motes. Now multiple sessions would probably average those out, so maybe you get lucky, but overall flats are the least time extensive calibration frame for me, so I would take them either way.




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