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possible flats mistake . . . will it work?

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#1 gatehealing

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Posted 16 May 2022 - 01:15 PM

I am using an adjustable white flat screen for my Flats light source. I have been getting it adjusted so that my exposure time is about 3.5sec. I seem to remember 2-4 sec is better than setting to Automatic exposure time in asiair pro.

 

(camera is asi2600mc pro)

 

Here's the thing. I was shooting new flats for a new UV-IR filter that was a little dusty to process last night's subs. I mixed up the exposure time understanding for bias and flats, and went for 0.2 sec, and adjusted my light source so that my ADU average was ~30,000. Unfortunately, I had cleaned off my filter before I realized the issue (I was just going to reshoot flats after next shoot), so I cannot just re-shoot the flats as the dust motes are gone.

 

Will my 0.2 sec ~30,000 adu average flats work ok? I think so, and will try it just to see, but wanted to get an idea of if I even need to worry about this in the future (assuming I don't blow off glass first) . . . ie, if I do this again, am I ok to just leave it since the adu average is correct and the motes are correct.

 

Thx!

Jon



#2 bobzeq25

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Posted 16 May 2022 - 01:52 PM

30,000 ADU (16 bit) on a 2600 is absolutely fine for flats.  It's not a mistake.


Edited by bobzeq25, 16 May 2022 - 01:52 PM.

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#3 OldManSky

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Posted 16 May 2022 - 01:57 PM

Bob's right.

And as the 2600MC isn't one of the few sensors that have problems with very short exposures, there shouldn't be any issue at all.



#4 gatehealing

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Posted 16 May 2022 - 02:49 PM

Great! Glad that the short exposure for flats won't be an issue for this.

 

Thanks!

Jon




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