The images produced by Ekos are shifted 10 pixels in width en 5 pixel in height compared with Adobe Digital Photo Professional and ASTAP.  This is not a major problem but doesn't allow the make darks outside Ekos.

I have compared hotpixels from FITS images taken with Ekos/Astroberry with CR2 darks and analysed them with Adobe Digital Photo Professional and ASTAP 1.0.0RC2. All images are in 5184 x3456 pixel format These are the positions of two hotpixelsCR2 dark using DPP (Adobe), positions 18, 3141 and 152, 2802 (counting starts at zero)
CR2 dark using ASTAP, positions: 19, 3142 and 153, 2803
FITS light by INDI, positions: 29, 2147 and 163, 2808So there is a shift of 10 in width and 5 in height between the INDI FITS and the CR2 dark. The fault lies in Ekos/INDI. For ASTAP the position of the .CR2 hot pixels are exactly the same as with Canon "Digital Photo Professional". For INDI FITS file the extracted 5184 x3456  cropped-active-area  lies not in the middle of the full-active-area of 5202x3464 pixels but at the side. In Libraw the left and right margin of the cropped active area (thumb) are defined  S.raw_inset_crops[0].cleft and  S.raw_inset_crops[0].ctop and have the values for the tested image 168, 56 pixels. The margins for the active area are left 158, top=52. The difference is the same 10 and 5 pixels.

I have idea where to place a bug report. Maybe somebody can do that.


Raw size: 5360x3516
Active area size: 5202x3464
Default cropped active area: 5184x3456
Margins active area: left=158, top=52
Margins cropped active area: left=168, top=56

  • A + C:   The Active Area, which is the largest area from which a useful image can be formed.
  • C:   The Crop Area, which is the subset of the Active Area which many raw converters convert into a useful image. The main reason why C is smaller than A is to provide some extra pixels all around for a raw converter's demosaicing algorithm to use.
  • :  Masked Area, used by some cameras, especially Canons used a dark.