Flats not doing anything

Hi Petra @petelaa,

That's looks a bit odd indeed ;-(, this is on APP 1.059 ?

I am working an a very big upgrade of APP's calibration engine for it's next release.

It would be most usefull if I could have a look at your data for testing purposes? I would only need a a couple of lights, bias and flats.

If okay, send them to support@astropixelprocessor.com using wetransfer.com.

Are the flats, lights and bias all the same ISO ?

Kind regards,

Mabula

lights and bias iso 1600, flats iso 100, BPM don't know. But this used to be no problem at all. Shall I send 5 of each to you?

Not sure if I use 1.058 or 1.059, will look that up when I send you the files, tomorrow .

Great @petelaa 😉 thank you.

The BPM doesn't matter.

If the flats are ISO 100 , APP  (version 1.059 and lower) needs an ISO 100 masterbias as well for the flats. ( In APP 1.060, this requirement will be removed though.. )

So currently, without a ISO100 masterbias, the bias signal and pedestal/offset won't be subtracted from the flats and this is needed for flat-field calibration.

So for now, shoot some ISO100 bias and create a masterbias, then create a new masterflat where this masterbias is loaded next to the flats. Then the masterflat should work.

Cheers,

Mabula

Great! Will do!

It worked, thanks. I won't be sending you the files now.

Little bit of feedback though: if APP is not applying the flats, then why (see first screenshot opening post) does it label the light with an 'F'?

@petelaa,

Thanks, glad it worked now 😉

Yes, good point, it should have applied the flats though, but since the masterflat didn't have the bias pedestal/offset subtracted, it looked like nothing was happening. ( If the exposure of the flats was very short then this could be the case.)

I'll make sure that in APP 1.060 things like this won't happen again though 😉

Mabula

👍 👍 Thanx & keep up the good work!