Transparency issue when converting from EXR to PNG - Arnold Maya

pjscottartist

Hello,

I've run into an issue when after rendering an image in Arnold Maya.

I've included images to illustrate the issue. In this scenario I'm working on a car windshield.

When I save an image with a transmissive material on a transparent background in EXR format I get the correct results. When saving an image in EXR format at 32bits the alpha values are correct. The specular / reflective values are displayed correctly on the glass.

However when I change the image mode to 16bit in photoshop, or save my render as a png from Arnold then the alpha values appear to be incorrect.

I understand that when working with EXR's the image format is not meant to deviate throughout the pipeline. I also understand that a 16bit image cannot hold the same information as a 32bit image.

However it would be handy if I could have a way of creating a 16bit image with the correct alpha values. Hope this makes sense.

Is there something in Arnold / Maya I am missing?

Any suggestions? Many thanks in advance.

Eric Chadwick

Try saving a 16bit EXR just to see what happens. Though I bet this is simply because PNG alpha might be only storing albedo alpha not reflection/specular.

oglu

Have you tried to save it with nuke. We did all our conversions from exr to png in nuke cause PS messed it up.

Adobe has still no clue how exr files work.

poopipe

substance designer can also convert without ruining the data if you don't have nuke to hand 

pjscottartist

thank you for your replies. I don't have Nuke but I have Substance designer so will try that. Many thanks again.