Out of interest, I have just manually tried stacking via Siril alone, and the stacked result is a blank light grey image.
I have also successfully stacked the same files with DSS (Sigma clipping and Entropy) and Pixinsight’s WBPP, SubframeSelector and ImageIntegration routines. Both produce expected results.
Looks like there is something going on with Siril, but I don’t know what. I have reinstalled the program, but to no avail.
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.
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?
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.
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.