Disabling Pass Through leaves me with no Image at all

Hello there,

I'm starting to learn Fusion 9 and I'm not entirely sure the Topic explains my Problem correct so here all all the informations I can give you.


I have a Background-Node (plain Color) and a Shadow (Loader-Node) wich both go into a Merge-Node (Background to Yellow and Loader to green).
This Merge-Node goes with another Loader-Node into a 2nd Merge-Node (Merge to Yello, Loader to green)and so on. (I'm try to build a Car outof 32bit exr files)

I view the 2nd Merge-Node in one of my Viewers (1 or 2 does not matter) and as soon as I disable the original Background, my Viewers go blank, same Thing happens if I disconnect the 1st Merge-Node from the 2nd and I have no Idea why.

Background + Loader = Merge
Merge + Loader = 2nd Merge

I hope I could explain my Problem here a little bit, if something is unclear, I'll try my best to explain it further.

A Merge gets its format from whatever is plugged into the Background (yellow) input. So if you disable the Background node that is feeding your first Merge, everything following has lost its knowledge of the correct size, bit depth, etc. As a result, you get an error instead of an image.

If I am following your reasoning, you want the ability to temporarily disable the color so you can see the car on either black or the transparent checker? If so, I recommend inserting a ChannelBooleans set to "Clear" right after the Background node. That will set all of the pixels coming in to black with no alpha (0,0,0,0). Disable it to get your original background color.

Thanks for the help.

I thought it had something to do with that, but could not wrap my head around it, now I feel stupid