Hello everyone !
I’ve been having a problem for quite some time on Create, and I wanted to share it with the community (and especially with the developers).
During a rendering (whether in Real-Time or in Path Tracing), the alpha channel which is saved in the output files is…very imprecise…
Insofar as I integrate my renderings into compositings, it often (or even systematically) happens that the outline of these sequences (therefore in the foreground) have a very ugly outline (or a very apparent outline in the event of a big difference between the background and the elements in the foreground).
I am attaching 3 images that will better describe what I want to express :
In my example, I simply embedded an object (Darth Vader’s helmet, WIP, don’t judge…) in an empty scene, with a red Dome Light, to maximize the contrast between the background and the object.
Here you see the raw rendering (without alpha layer).
Then you will find below the same rendering, but with the “Save Alpha” box checked and, if you look closely, you can see a red “line” around the object.
This is what I call “Imprecise Alpha”
On the following image, I made, under Maya, a simple green screen to separate the object from the background, and I composited the whole thing (raw rendering under Create and green screen rendering under Maya), we can clearly see that the red “line” has disappeared !
I think with these images, it will be much clearer.
Is there, in your opinion, a way to “refine” the generation of this alpha ? I can always use the green screen technique, but it’s longer, more complicated and it generates a lot more files…for nothing !
Any help will be welcome !
Thank you for your time and expertise !