I’m not sure where to find the visualisation sliders?
I have toggled through the display modes, and usually use the “Histogram” or “Autostretch” modes to get a clear view of the linear stack ready for Background Extraction.
Loading the stack into Startools produces the same blank image.
Hello,
Am I right in thinking there’s no fix for this then?
Thanks
Right,
After some investigation I have concluded that there is something wrong with the way Siril processes Darkflats.
I re-ran my SirilIC project, this time without the Darkflats and sure enough the stack completed successfully.
With another attempt, I then tried importing the Darkflats into SirilIC’s “Offset” field, and the stack again completed without issue.
For sure there is nothing wrong with my Darkflats, as they were taken with exactly the same settings and time as my flats (obviously with the optics covered), and as previously mentioned, they work perfectly with DSS and Pixinsight.
So, going forward, until this is fixed in Siril, would I be better off stacking my Darkflats as Bias frames, or omitting them altogether?
Thanks
That would be very strange because I do it very often, and I’m not the only one :).
Maybe that your workflow is not as expected I would say.
Without any images it is very difficult to say something.
But I can say that the way we use the dark flat is the right way. It is just a subtraction.
And how would you go about loading Dark flats into Siril?
My image and calibration files are available, should you wish to test.
Dark flats are subtracted in a first pass to the flat sequence. As we generally do with biases.
Thats’s not what I’m asking - I know darkflats are subtracted from flats. 
Siril’s Pre-processing tab accepts offset, dark and flat master calibration frames. My question is where do you load the master darkflats? The offset field?
I’m sorry but it was my answer. Load a flat sequence and preprocess with your dark flat. Stack to obtain your master flat.
Then load you light sequence and preprocess with this master flat and with your master dark.
Forgive me, but I simply don’t understand how i can “preprocess with my dark flat”.
Here I see 3 fields, offset, dark and flat. How/where do I subtract my dark flats here?
FWIW, here is the successful calibration flow when I load dark flats into the bias/offset field using SirilIC…
And here is the original calibration flow, which always fails with dark flats entered in the dark flats field…
I have blinked each and every one of my lights, darks, flats and dark flats in PixInsight to ensure there are no spurious subs where they shouldn’t be. Everything is in order.
Thanks
Yes.
But do what I say.
That’s it.
I can’t help you with Sirilic. But if you follow what I’m saying it will be ok.
You can put your “dark flat” master in the dark field. You subtract a dark frame to a light frame, except here your light is a flat.
I’m sorry but “preprocess the sequence with your dark flat” means nothing to me without clearer instructions (How, exactly?).
From reading this guide, it is clear to me the that in the STEP TWO: FLAT FRAMES section, the flats are pre-processed with the masterbias referenced in the “use offset” field, which makes perfect sense. All I am asking is instead of masterbias (which I don’t have) where do I source/enter/reference my masterdarkflat? Again, there is no obvious “use darkflat” field.
There appear to be 2 choices:
"use offset" or
"use dark"
Do you get what I mean with this?
Regards
After testing with “dark flat” master in the dark field, I see typical 294 starburst ampglow.
Preprocessed this time with “dark flat” master in the offset field and everything is fine. I think I will stick with this for now.
Thanks for your assistance.
Regards,
Mark
What is a darkflat? It is just a bias frame with thermal signal.
So yes, put it in the bias field.
why does it change anything between offset and dark subtractions? does it have to do with cosmetic correction?
Yes probably (or optimization)
hi,
can you check the debug option in sirilic preferences and redo the test and send me the file “sirilic-trace.log” once sirilic is closed.
can you also send me the following files:
“sirilic.log”, “sirilic-part1.ssf”, “sirilic-part2.ssf”
