Enabling Transparency in Film settings causes the alpha layers to be stacked when rendering

[AdalynBlack]

When rendering with transparency enabled and having partial transparency (i.e. fog), the renders from each system stack on top of each other, and the alpha channels add instead of averaging, resulting in bands of higher opacity in the overlapping regions of the image, as seen in the attached render

This is how the render should look

[AdalynBlack]

As a note, rendering as an animation works just fine. It's only when rendering single images that this occurs

[luckycatx]

As a note, rendering as an animation works just fine. It's only when rendering single images that this occurs

Have you tried turnoff the "workaround" setting?

[AdalynBlack]

oh, I didn't know that was a thing. I'll try it

[AdalynBlack]

both workaround enabled and disabled causes the same issue, just in different spots of the image

[luckycatx]

both workaround enabled and disabled causes the same issue, just in different spots of the image

That's kinda weird, I just tried to render a car model and I set film transparency enabled and the result it came is normal. Maybe it is because the partial transparency problem, not sure. I don't know how to use blender but I'm trying to figuring out how's the program working.

[AdalynBlack]

It's definitely the partial transparency that's causing the problem. Add in a mesh using a principled volume shader

[pokeslog]

I don't think he's developing this anymore.

[LogicReinc]

I'm, just extremely infrequently due to my work taking most of my time.

The overlap is clearly a result of how the software merges shots, to prevent lines in renders due to inaccurate rounding, it overlaps them slightly. This works fine if images are opaque, not so much for transparent.
A mode could be added that tries to accurately line up crops to not need this overlap.
Workaround is unrelated to this issue, it has to do with tile ordering.