Which G’MIC version (type gmic version) are you using? Also read about saving in the TIF format starting here: Astrophotography - Stacking images with GMIC command line - #2 by afre.
Which G’MIC version (type gmic version) are you using? Also read about saving in the TIF format starting here: Astrophotography - Stacking images with GMIC command line - #2 by afre.