Object with Transparent material renders with black background

[Alan_WP]

Good day everyone,

I have come across an issue, unsure what the cause is, I have researched and checked all the obvious culprits listed within the forums and Autodesk articles.

1. The material is a Arnold Standard surface,it  has no maps and is part of a multimaterial.
2. I am using GPU Arnold 5.9.1.1
3. 3ds Max 2027
4. Export format .exr (viewed in Photoshop using EXR-IO).

Below you will find screenshots of the settings. I would greatly appreciate it, if someone has any ideas to share.

Many thanks in advance!

[Alan_WP · Accepted solution]

Hello All,

I found the culprit, there was no opactiy set within the material:

Originally this was white. I used the MAXtoA.mat librry'Thin Plastic' as a basis, as it looked transparent in the renderings, I figured, it would be, as it is from a material library from Autodesk. Unfortunately, it isn't truely transparent. If I have made a mistake somewhere, please feel to correct me. 

Many thanks