The image can be solved and calibrated with PCC without problems:
However, after PCC a green cast remains. I don't know why. Is the image in linear state?
I took your advice and started over with the stacking and registration process, saving everything in XISF format this time. I had no better luck with an XISF image using the parameter settings you described earlier (using Antares as the reference, PPMXL as the catalog, Limit magnitude to 10). It still fails (log capture below). I uploaded the unstretched XISF file
HERE.
Can anyone tell me what I'm doing wrong?
PCC Log output:
==============
Reading image:
C:/Users/Bill/AppData/Local/Temp/PCC_T_4GKWRFNSF0CN.xisf
Loading image: w=6264 h=4180 n=3 RGB UInt16
515 FITS keyword(s) extracted.
Seed parameters for plate solving:
Image coordinates: RA = 16 29 24.460, Dec = -26 25 55.21
Resolution: 13.598 as/px
Starting StarAlignment iteration
Catalog PPMXL already loaded.
Catalog PPMXL size: 57418 objects
Using the triangle similarity star matching algorithm.
C:/Users/Bill/AppData/Local/Temp/stars.csv:
Scanning star data: done
9736 stars.
PCC_T_4GKWRFNSF0CN:
Structure map: done
Detecting stars: done
57186 stars found.
* Reference image: Limiting to 2000 brightest stars.
* Target image: Limiting to 2000 brightest stars.
* Distortion correction: Iteration 1 of 50
Matching stars: done
266 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #2
useScaleDifferences=true
* Reference image: Limiting to 2000 brightest stars.
* Target image: Limiting to 2000 brightest stars.
* Distortion correction: Iteration 1 of 50
Matching stars: done
413 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #3
...
* Previous attempt failed - this is try #20
useScaleDifferences=true
* Reference image: Limiting to 3000 brightest stars.
* Target image: Limiting to 3000 brightest stars.
* Distortion correction: Iteration 1 of 50
Matching stars: done
580 putative star pair matches.
Performing RANSAC: done
*** Error: Unable to find an initial set of putative star pair matches.
*** Error: The image could not be aligned with the reference star field
Please check the following items:
The initial coordinates should be inside the image.
The initial resolution should be within a factor of 2 from the correct value.
Adjust the star detection sensitivity parameter, so that the script can detect most of the stars in the image without mistaking noise for stars.
The catalog should be matched to the image. Choose the appropriate catalog and magnitude filter, so that the number of stars extracted from the catalog can be similar to the number of stars detected in the image.
*** Error: Unable to plate solve image: Alignment failed
This usually happens because the initial parameters are too far from the actual metadata of the image.
** Warning: Process finished with errors:
PCC_T_4GKWRFNSF0CN.xisf: The image could not be plate solved
*** Error: Failure to plate solve image: Rh
ph_Normal_DBE
Reading swap files...
1808.471 MiB/s
<* failed *>