A dog on a rock

Heavy fog today morning up on Kopparhatten (Copper Hat), then shot a wild hound just as it started clearing up.

One reason I stitched this panorama was to try out how today’s software versions handle working with unclipped 32-bit floating-point images. I was pleasantly surprised that there was only one snag.

  1. Using RawTherapee 5.5-137-g05bc7b245, I only applied a custom DCP input profile (it made no difference from the one RawTherapee already ships), used chromatic aberration correction, bumped exposure compensation +1EV and disabled out-of-gamut clipping (which didn’t appear to make any difference either, since there are no out-of-gamut colors in this foggy morning scene); no curves or anything to make the image look nice, that’s done last.
  2. I exported to 32-bit floating-point TIFFs.
  3. I stitched them using Hugin 2018.0.0.5abfb4de7961. Opening these 32-bit TIFF files took perhaps twice as long as opening 16-bit files, which is to be expected. Automatically creating control-points, geometric and photometric optimization went smoothly. However, the OpenGL viewer is not your friend. It does not handle 32-bit images correctly - this is the one snag. It shows them far too bright and so is difficult to use:

    The slow viewer shows them properly:
  4. Finally, back to RawTherapee to make the image look aesthetically pleasing. When saving the stitched panorama in Hugin, I selected the “high dynamic range” option, in TIFF format. The resulting TIFF lacks an ICC profile, so when opening it in RawTherapee it has wrong colors and wrong gamma:

    You must apply the same profile as was used when exporting the raw files to TIFF, which in this case was sRGB. So I applied sRGB, bent a curve here, made a tweak there, cropped to where it matters, and done.

More testing needs to be done, specifically seeing whether 32-bit floating-point TIFFs with no out-of-gamut clipping of a high dynamic range scene retain data in the highlights, and whether the resulting 32-bit panorama hasn’t lost any data on the way, but so far things look promising.


First of all, lovely image.

Was it out of self-defense? :stuck_out_tongue_closed_eyes:

That and colour management has been the problem for me. Also, the stitching sometimes fails to work with the same parameters that worked a second ago. Weird.

@Morgan_Hardwood this is great! (big fan of Hugin panoramas here) and love the wild hound :slight_smile:

Very interesting country, that Sweden. The wild hounds have coats! Are they government issued?

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Wow! Nice one @Morgan_Hardwood!!!

It would be wonderful to see a video about the whole process. If you do it again and have more time… :wink:

P.S: I wonder what it could look like with a little colder color temperature :thinking:

Results are in. In Hugin, one must save the panorama using “Panorama Outputs: High dynamic range” to TIFF or EXR in order for clipping to not occur.

Now you know why Swedes pay high taxes.

I will do that at some point.