Author Topic: Flat Darks  (Read 2273 times)

Offline rdryfoos

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Flat Darks
« on: 2018 March 31 15:35:41 »
Is there a way to use flat darks in the BPP calibration script?  I use that exclusively to calibrate and would not like to have to go the manual route.  I suppose I could manually make the flat darks and manually use them at the right time......but what would the right time be?
Rodd

Offline Geoff

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Re: Flat Darks
« Reply #1 on: 2018 March 31 16:02:10 »
Put bias, flats and flat darks into BPP. This will generate a master flat. Next time around put in darks, lights, bias and master flat. Don't forget ti tick the box"use master flat"
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Offline rdryfoos

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Re: Flat Darks
« Reply #2 on: 2018 March 31 16:54:06 »
Put bias, flats and flat darks into BPP. This will generate a master flat. Next time around put in darks, lights, bias and master flat. Don't forget ti tick the box"use master flat"
  But there is no place for flat darks--just bias, darks, flats and lights

Offline Geoff

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Re: Flat Darks
« Reply #3 on: 2018 March 31 19:12:55 »
A flat dark IS a dark. Just load it into the darks section. A flat dark is a dark frame taken at the same exposure as your flats.
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Offline rdryfoos

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Re: Flat Darks
« Reply #4 on: 2018 March 31 21:16:25 »
A flat dark IS a dark. Just load it into the darks section. A flat dark is a dark frame taken at the same exposure as your flats.
So PI will separate them like it does with different colored flats, and will know what to do with them?  It will know to use them to calibrate the flats and not the lights?

Offline RickS

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Re: Flat Darks
« Reply #5 on: 2018 March 31 21:20:00 »
So PI will separate them like it does with different colored flats, and will know what to do with them?  It will know to use them to calibrate the flats and not the lights?

No, BPP is not that smart.  That's why Geoff said to run BPP once with bias, (flat) darks and flats to create master flats then run BPP again with bias, (normal) darks, master flats and lights.

Offline rdryfoos

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Re: Flat Darks
« Reply #6 on: 2018 March 31 21:24:05 »
So PI will separate them like it does with different colored flats, and will know what to do with them?  It will know to use them to calibrate the flats and not the lights?

No, BPP is not that smart.  That's why Geoff said to run BPP once with bias, (flat) darks and flats to create master flats then run BPP again with bias, (normal) darks, master flats and lights.
Can you run it just to create master calibration stacks?  Without light frames to calibrate?

Offline RickS

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Re: Flat Darks
« Reply #7 on: 2018 March 31 21:36:30 »
Can you run it just to create master calibration stacks?  Without light frames to calibrate?

Yes!  It will warn that there are no lights but you can continue and it will build the masters.

Offline rdryfoos

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Re: Flat Darks
« Reply #8 on: 2018 March 31 21:38:47 »
Can you run it just to create master calibration stacks?  Without light frames to calibrate?

Yes!  It will warn that there are no lights but you can continue and it will build the masters.
  Great...thank you.  I guess I might as well start using flat darks--they are easy enough to take and use.
Rodd