PixInsight won't use my flats!

[pipnina]

I've been using Pix for a short while now. And I've generally found it to do things a bit more hassle-free (if a little more complicated) than DSS, however today it has baffled me.

I collected my flats before the session started as usual, and then collected my lights as I went to bed. Today I try to stack the 9 good lights with my flats and I find Pixinsight will happily recognise that the lights and flats belong together, generates a master flat, but won't actually use it on my light frames!

As you can see in this comparison between single sub and stack, not only is the vignetting unchanged in shape but the dust mote remains unchanged as well.

The stacking process did not even generate a "calibrated" folder as I have seen it do in the past!

And in my WBPP screen it even recognises that the two belong together with the green tick! Yet even manually changing the flat setting in the top right from auto to manually select the flat frames, they still do not apply! I've even done this without any darks or bias or darkflats before and it's calibrated just fine.

I'm a bit lost at the moment, hopefully someone here knows what I'm doing wrong! : (

Light_003.fitsLight_002.fitsLight_001.fits

Flat_003.fitsFlat_002.fitsFlat_001.fits

I've attached the bare minimum Pix will want to perform a stack in case anyone would like a go

 

Many thanks!

[The Lazy Astronomer]

Not really a solution to your problem, but as you've only got a few lights, for a workaround you could apply the master flat manually to each one using pixelmath: light/master flat 

[Aramcheck]

I don't use WBPP but the ImageCalibration process worked fine on the single file I tried. Any reason you haven't taken Darks or Bias frames?

Cheers
Ivor

[pipnina]

30 minutes ago, Aramcheck said:

I don't use WBPP but the ImageCalibration process worked fine on the single file I tried. Any reason you haven't taken Darks or Bias frames?

Cheers
Ivor

 

I have read that bias frames aren't consistent in terms of read noise or linearity on CMOS sensors, and it's calibrated fine without them in the past. As for darks, I have tried to build a library of dark frames, but I always end up unable to isolate the camera fully from light (even in a room dark enough for me to need to sit down for a few minutes to see, camera under a tshirt, plugged with its rubber dust cap and socks pulled over the end, some light still got through!)

Maybe I can manually calibrate them this way, since it seems like the tool allows it to be done in batch! Thanks for the workaround I'll give it a go soon!

[Aramcheck]

For my CMOS OSC camera I just use darks which match the exposure time (& temperature) of the light frames & a second set which match the exposure time (& temperature) of the flats.

The darks are taken with the camera by itself (not attached to the scope) with the cap on & then integrated into a Master Dark for the lights & a Master Dark Flat for the flat frames. (And as I had a coma corrector fitted at the time I used some aluminium foil over the top of the plastic coma corrector cap). The darks were also taken in a dark environment, though I doubt that made any difference. I've not had any problem with light leaks...

Best of luck!
Ivor

[Anne S]

I notice you've got dark ticked in the  calibration area. I remove the tick when I don't use darks. I always use bias. I'm using a SXVR694 that doesn't need darks. PI then warns me I don't have any darks but continues calibrating anyway. Maybe that's why you don't have a calibration folder. I don't think it's using your master flat.

 

 

[The Lazy Astronomer]

I never really understand the issue people have with darks - reading the extraordinary lengths people go to and still suffer from light leaks - I simply don't get it. I don't even take the camera off the scope, whenever I need to shoot mine, I just do it at night with a jacket or two loosely thrown over the setup and don't see any problems whatsoever.