My fits files are coming out black and white rather than color. I'm using a Canon T7 DSLR. How do I correct this?
Siril displays the fits header:

SIMPLE = T / file does conform to FITS standard
BITPIX = -32 / number of bits per data pixel
NAXIS = 2 / number of data axes
NAXIS1 = 6020 / length of data axis 1
NAXIS2 = 4016 / length of data axis 2
EXTEND = T / FITS dataset may contain extensions
COMMENT FITS (Flexible Image Transport System) format is defined in 'Astronomy
COMMENT and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H
MIPS-HI = 65534 / Upper visualization cutoff
MIPS-LO = 0 / Lower visualization cutoff
BZERO = 0. / offset data range to that of unsigned short
BSCALE = 1. / default scaling factor
INSTRUME= 'Canon EOS 1500D' / instrument name
TELESCOP= 'Explore Scientific iEXOS100' / telescope used to acquire this image
DATE = '2024-07-26T17:35:19' / UTC date that FITS file was created
EXPTIME = 120. / Exposure time
XPIXSZ = 3.72 / X pixel size microns
YPIXSZ = 3.72 / Y pixel size microns
XBINNING= 1 / Camera binning mode
YBINNING= 1 / Camera binning mode
FOCALLEN= 289. / Camera focal length
CCD-TEMP= 34. / CCD temp in C
IMAGETYP= 'Light ' / Type of image
BAYERPAT= 'RGGB ' / Bayer color pattern
XBAYROFF= 0 / X offset of Bayer array
YBAYROFF= 0 / Y offset of Bayer array
PROGRAM = 'Siril v1.2.2' / Software that created this HDU
RA = 314.92107 / Image center Right Ascension (deg)
DEC = 44.424566 / Image center Declination (deg)
HISTORY Asinh Transformation: (stretch=1000.0, bp=0.20000)
HISTORY Histogram Transf. (mid=0.027, lo=0.000, hi=1.000)
HISTORY Histogram Transf. (mid=0.052, lo=0.000, hi=1.000)
HISTORY Binning x1 (average)
END

FITS files contain R, G and B pixels that need to be decoded into colors. This decoding is called debayering because the pixels are ordered in a Bayer-matrix which is

R G
G B

as can be seen in the BAYERPAT item in the FITS header.

    I think the problem is the NAXIS is 2 but I don't know how to change that.

    dclemmons39 The imagea are in color. You just need to debayer them. ASIStudio can do that for you.

      Here's the fits header from an image taken earlier this month. It does have color. The only difference I see is the NAXIS is 3. How do I control that from ASIAIR?

      SIMPLE = T / file does conform to FITS standard
      BITPIX = -32 / number of bits per data pixel
      NAXIS = 3 / number of data axes
      NAXIS1 = 3434 / length of data axis 1
      NAXIS2 = 1381 / length of data axis 2
      NAXIS3 = 3 / length of data axis 3
      EXTEND = T / FITS dataset may contain extensions
      COMMENT FITS (Flexible Image Transport System) format is defined in 'Astronomy
      COMMENT and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H
      MIPS-FHI= 1. / Upper visualization cutoff
      MIPS-FLO= 0. / Lower visualization cutoff
      BZERO = 0. / offset data range to that of unsigned short
      BSCALE = 1. / default scaling factor
      INSTRUME= 'Canon EOS 1500D' / instrument name
      TELESCOP= 'Explore Scientific iEXOS100' / telescope used to acquire this image
      DATE = '2024-07-08T01:59:53' / UTC date that FITS file was created
      DATE-OBS= '2024-07-03T06:16:11.843577' / YYYY-MM-DDThh:mm:ss observation start,
      STACKCNT= 240 / Stack frames
      EXPTIME = 30. / Exposure time
      XPIXSZ = 3.72 / X pixel size microns
      YPIXSZ = 3.72 / Y pixel size microns
      XBINNING= 1 / Camera binning mode
      YBINNING= 1 / Camera binning mode
      FOCALLEN= 289. / Camera focal length
      CCD-TEMP= 36. / CCD temp in C
      FILTER = 'mixed ' / Active filter name
      IMAGETYP= 'Light ' / Type of image
      BAYERPAT= 'RGGB ' / Bayer color pattern
      XBAYROFF= 0 / X offset of Bayer array
      YBAYROFF= 0 / Y offset of Bayer array
      PROGRAM = 'Siril v1.2.2' / Software that created this HDU
      RA = 311.94369 / Image center Right Ascension (deg)
      DEC = 30.304774 / Image center Declination (deg)
      CRPIX1 = 1544.66743978 / Axis1 reference pixel
      CRPIX2 = 337.789031984 / Axis2 reference pixel
      CRVAL1 = 311.402104684 / Axis1 reference value (deg)
      CRVAL2 = 30.4825820151 / Axis2 reference value (deg)
      CDELT1 = 0.000737919684134241 / X pixel size (deg)
      CDELT2 = 0.000739132014441676 / Y pixel size (deg)
      PC1_1 = -0.0813524791531773 / Linear transformation matrix (1, 1)
      PC1_2 = 0.998392270324605 / Linear transformation matrix (1, 2)
      PC2_1 = -0.99505062231753 / Linear transformation matrix (2, 1)
      PC2_2 = -0.0804988790317037 / Linear transformation matrix (2, 2)
      END

      Oh I missed that. Looks like you're right. Also the dimensions of the images are different. Was an update of the ASIAir firmware installed between the two pics? FWIW it is possible to edit the FITS headers and modify those numbers. Then they should appear as color images again.

      I seem to remember having seen a thread about issues with either the latest camera drivers or with the latest ASIAir software. I cannot find it now.

      Are you on Android? If yes I'd recommend reverting to the previous version. You'll need to flash the ASIAir, uninstall the ASIAir app, install the previous version and update ASIAir again. This will not install the latest version of ASIAir but the previous one.

      If you're on iOS then there's nothing you can do but wait until ZWO fix this. Let's see if they chime in on this thread.

      Yes. I actually had 2 problems after the update. The other problem was fixed by installing the previous version of app.

      By the way this is asiair mini so it doesn't have an sd card.

      11 days later
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