Flats exposure length

[Anthonyexmouth]

How important is ADU for flats? Just made an el flat panel and added enough paper to get the right adu with the flats wizard in Nina. It's something like 2.87766s , I made that up but you get the point. Can I for ease of taking flats and dark flats just use 3s subs or is accurate 30% adu more important? 

[ONIKKINEN]

I would not worry about that difference. If your histogram peaks for all the colourchannels are somewhere around 30-50% then all good, but most importantly if the flats actually work. So you can test this by just applying the 3s flat to a sub and see if you get good calibration? Probably works just fine.

[ollypenrice]

The ADU value is tolerant but you might need a lot of paper to get up to 3 seconds...

Olly

[Anthonyexmouth]

2 minutes ago, ollypenrice said:

The ADU value is tolerant but you might need a lot of paper to get up to 3 seconds...

Olly

6 sheets of printer paper. 

[iantaylor2uk]

Not sure why you want such a long exposure time for flats. I use the auto exposure function in the ASI Air Pro and use a flat panel with no paper. With just an IR/UV filter the exposure time is around 30 milliseconds or so, whereas with the L-enhance filter the exposure time is around 300 milliseconds. The flats used from these short exposures seem to work fine for my ASI 071 MC Pro camera. 

[Anthonyexmouth]

12 minutes ago, iantaylor2uk said:

Not sure why you want such a long exposure time for flats. I use the auto exposure function in the ASI Air Pro and use a flat panel with no paper. With just an IR/UV filter the exposure time is around 30 milliseconds or so, whereas with the L-enhance filter the exposure time is around 300 milliseconds. The flats used from these short exposures seem to work fine for my ASI 071 MC Pro camera. 

I'm using a 294. They need long flat exposures. 

[AstroNebulee]

With my 294MC pro and AApro, using a flat panel and about 4 sheets of printer paper it's around 2.5 seconds with the auto flats. Histogram peak is in the 40-50% area. 

Cheers 

Lee