OpenEXR Multilayer Questions


After I got into compositing I have started to use OpenEXR Multilayer which is awesome, really :slight_smile: However, I seem to have a couple of problems with it which I can’t find answers for;

  • Whenever I try to select a compression the file size is still the same. No matter what I pick (even “None”), re-render and save, the file size is identical. Am I doing something wrong or have I perhaps encountered a bug?
  • I can’t seem to select “half” accuracy, like you can do on singlelayer OpenEXR. This would really make a difference since the filesizes are so large. Is there a technical reason for this only being availbale for single layer files or has this just not been implemeted yet?
  • Also, although less import, the preview option also seems missing on Multilayer. I would love to have the combined render as a small, and easy to work with jpg. Is this missing for a reason?

Thanks in advance!

Multilayer is not really for an image output format. It can combine multiple render passes from multiple scenes so there may not really be a single ‘combined’ render. What would you then show as the preview ? It as an intermediate format so you would not want to lose any data.

Thanks for the answer! Yes, the preview might not really fit these files under all circumstances, but I believe it would work by just saving the first combined pass Blender creates. Or is that not possible?

This is not to see exactly everything a file includes but to be able to just see what the images are of in your file explorers since exr files has no preview, and to easily playback the rendered animation thanks to the small file sizes :slight_smile:

All the things you plan to do later in compositing will of course not be seen in these preview files but they are just there to make it easier to see what you have rendered.