Renders of Deep EXR images written out from Katana with RenderMan 21.3 and lower can’t be read in Nuke unless they are set up a certain way.
The Deep EXR images rendered by RenderMan 21.3 and lower can’t be read by Nuke due to two main issues:
- A bug in RenderMan for Katana (RfK) that causes the image to be written without alpha data. The file won’t be loaded in Nuke unless it has an alpha channel.
- Nuke will only read EXR data that was written out in scanline mode. However, RenderMan defaults to writing deep EXR data in tiled mode.
The RenderMan team are aware of these issues and may be able to address them in the RenderMan 21.4 release. The full discussion of the problem on the RenderMan forums can be viewed here:
In the meantime, please see the attached example Katana scene, provided by the RenderMan team on the forum post mentioned above, that sets up the render output parameters necessary for rendering Deep EXR files readable by Nuke.
NOTE: only the .exr file extension is recognised by Nuke, and not files of type .deepexr . This means that the output of the above scene should be renamed from .deepexr to .exr for Nuke to read it correctly.