Versions: Blender, Gimp 2.9.3 (development version)

I am trying to make a texturing workflow based on using projecting images from camera to a model. In the menu in Texture mode there is an External tab which contains Apply and Apply Camera Image. Both of these buttons depend on bpy.ops.paint.project_image(image=image_name) function.

When I project a high dynamic range image, for example 16bit PNG or 16-32-floating exr onto 32 bit texture image all seems to work well. However when I save the resulting texture in Gimp and look at its histogram this is what I see:

levels histogram

It seems that in reality projected image only has 8-bit information. Is there a way to manipulate context for the project_image to make it output 16-32 bit dynamic range? Or may be there is another way to achieve high dynamic range projections?

Waveforms from a blender file example:

I used a the the same crop where all files had visual information.

  1. Baked into 32-bit texture (EXR)

Baked into 32-bit

  1. Camera render (EXR)

Camera render

  1. Projection of the Camera render (also EXR)

Projected Image

  • $\begingroup$ Is there a .blend file which we could download to troubleshoot the steps you took to create the 32bit render? $\endgroup$
    – hawkenfox
    Jan 10 '16 at 13:19
  • $\begingroup$ Blender file illustrating the problem is here $\endgroup$
    – dimus
    Jan 10 '16 at 15:30
  • 1
    $\begingroup$ And here is a related question $\endgroup$
    – dimus
    Jan 10 '16 at 15:31
  • $\begingroup$ As far as I know Gimp doesn't work yet at 16/32bit depth. $\endgroup$
    – user1853
    Jan 10 '16 at 19:01
  • $\begingroup$ Development version of Gimp 2.9.3 does work with 32 bit $\endgroup$
    – dimus
    Jan 10 '16 at 19:54

The ability to project high dynamic precision images had been added to Blender's master branch by Campbell Barton. Thanks Campbell!

See the corresponding issue


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