Hello - You will see by my singular other post saying hi, I am another newbie. I have tried looking for the answer (already solved lots of problems with threads in the forum!), but alas, not cracked it yet. This is my first C4d project and first 3d anything so please forgive my ignorance to many things...
I'm building a stage which has an arch and behind it I am inserting video/stills as it if was an LED wall. So big arch, transparent hole in the middle, render my PNG and stick it in premiere pro to insert videos into the gap. I have a placeholder object with and image mapped on it to look like the LED wall whilst still in cinema 4d.
On the stage I have some lights shooting upwards with visible light, as if they were bright stage lights cutting through haze/fog machine. It all looks good when rendered within C4D, or when rendered with my placeholder. However, when rendered with the hole in the arch as transparent, the beam fall off sort of loses intensity. So when inserting my content into that transparent whole the light looks like it's reflecting off of cinema 4D surfaces as it's much brighter/harder edged than it is over the transparent surface.
I know from what I have found this is probably going to be something to do with multi pass/atmosphere but I can't quite crack it. I'm happy with the way the lights within the stage and stairs look (LED tape effect), and in my attempt to fix the problem of the render it's been affecting the glow of those so hopefully I can make both look how they do within C4D in the render.
I've attached 4 images.
Rendered in C4D with placeholder for LED screen, rendered in C4D without (so transparent, showing as black), and rendered out then dropped into photoshop over a black background, showing how the visible light looks. Finally a full shot to give some context of what I'm doing.
FYI in terms of rendering I have been doing 3 layers. Starcloth back drop, set/stage/audience and then just the lecterns. In post I insert some FX videos in front of the star cloth to bring it to life a bit, then of course the "LED screen" in front of that but behind the set, then my green screened people in front of the set but behind the lecterns.