Multilayer EXR export error

[spoon48]

Hey guys,

i'm trying to export a multilayer exr of my Affinity Photo project (every layer in the project should be stored in a different channel). As i follow the instructions in the mannual i get the message "an error occurred while exporting to: ..." as soon as i click the export button. 

Anyone knows a solution?

[James Ritson]

Hi @spoon48, I've seen this before and can't quite remember how I fixed it—would it be possible to see a screenshot of your entire layer stack, and also your export settings (the expanded settings on the More dialog)?

Thanks!
James

[spoon48]

sure
here is a screencapture

[James Ritson]

Hi again, I think the export error is because of your layer stack. Check out the help topics on OpenEXR at https://affinity.help — particularly this one:

https://affinity.help/photo/English.lproj/pages/HDR/openexr.html

Generally, all of your pixel layers should have an .RGB or .RGBA affix (for example "Layer02.RGB" or "Layer02.RGBA" if it has a distinct alpha channel). If you don't specify layers as RGB pixel data they will be discarded on export.

The reason you have to do this is because Affinity Photo has lots of different layer types: pixel layers, image layers, curves, fills, groups, etc. The OpenEXR spec is much narrower and you have to dictate what type of channel information each layer becomes when exporting to EXR. If you don't specify the channel type, Photo will ignore or discard the layer in question during export.

If you have a pixel layer with a mask inside it, you must use the .RGBA prefix if you want to export the alpha channel separately—if you just use .RGB the alpha channel will be baked into the pixel layer and will be non-editable.

Separate colour channel information can also be exported, so you could affix layers with .R, .B, .G and .A etc and they will be stored as individual channels in the EXR document.

You don't appear to be working with any spatial layers like .Z or .XYZ so you can probably ignore them.

Embedded documents and placed images should be correctly rasterised as long as you give them an .RGB or .RGBA prefix.

Groups you will have to rasterise, even if you give them an .RGB prefix, otherwise they won't export. Right click the group and choose Rasterise to do this (make a duplicated backup beforehand and hide it though).

I'm actually struggling to reproduce the error message now—if you try the naming conventions listed above and are still getting the error message, please could I send you a private Dropbox link to upload the document so I can have a look? It would only be used internally and then deleted once the issue is addressed.

Thanks and hope the above helps,
James

[spoon48]

Thanks very much! the affix fixed it. Actually i can now even export layer within a group that have the affix

This makes Affinity so much more attractive for an mattepainting workflow!

 

[James Ritson]

Glad it's all working for you! I'll have to test the group export again, did you have layers within the group that you gave .RGB affixes for it to work?

If you have any other questions regarding EXR/32-bit/linear compositing etc don't hesitate to ask.

All the best,
James