Hello All,
it’s my first post and i’ve tried to solve this by research but i didn’t find the solution.
Here is the fabulous pass in After Effect from the V4`
And the shitty pass from the V5 
I haven’t change too much things, just fine tunning …
Tried to increase levels, but it’s always the same, everything is merged except few materials…
Do you have an idea of what causing this ?
Thanks for your help and i hope to solve this forever (not the first time)
I’ve solved the issue by importing the whole scene in a new blender file.
This works but it make loose a lot of time.
So it looks to be a a bug … i don’t understand what’s the problem … and i still hope to find a better way to solve this problem …
You realize, that you have not described your issue and it’s not really possible for anyone to understand what the hell you are talking about from what you have said as far, right?
Try describing what you are trying to achieve and what you do to achieve it and how it differs from your expectations(describe the expectations as well). Also provide context: What are you doing? Why? How? What is this for?
Don’t just post an image and say nothing about it. Nobody knows what it is or what it is supposed to be. How can anybody know that? Look at the image you posted! What is that? 
How are we supposed to know?
Try not to use words like “this”, “that”, “the” from the start. You should describe something and then refer to it with those. If you haven’t talked about anything specific, these words don’t refer to anything.
Hello Martin,
Sooorrrry, i’ll try to be more clear.
I work on Blender 4 with a recent machine, but i experienced this problem on diferents version from 3.3 to 4.1
I’m doing an animation render with cycle on an EXR Multilayered 32 bits and i do the composting in after effects. I use cryptomatte for color grading.
During 4 versions it works like a charm.
And after render the 5th version, all the ID has been lost and i can’t recreate them because many materials are merged like on the first screenshot. Just a cable is selectable alone.
I’ve tried to increase the level in the cryptomatte tab but it change nothing …
I’ve noticed that also render pass names has changed and i have to reconnect them …
exemple : combined is renamed image.
I’ll try to explore that path to find a solution.
I’ve solved the cryptomatte issue by importing the whole scene in a new file.
It works but it takes time, i hope there’s a better solution
If you can share a file, it makes it easier to get help.
Also, explain in detail what your workflow is, and how you set up your renders.
Otherwise it’s a guessing game 
I have had issues with Cryptomatte and PIZ 32bit Multilayer EXR compression in recent versions. Try ZIP maybe.
Thank you both of you
I’m rendering the sequence with the “new file” trick.
So i have to standbye researches, But i keep the hope to solve that.
@Robwu, My workflow is to modeling, animate 3D in Blender and then export a multilayered EXR sequence to After Effects for compositing and then, Overlays and texts.
I think i’ll be probably do the compositing in Blender more or less soon, But the cryptomatte pass will be still important to have the ability of masking overlays or text.
@MartinZ I’ll try other EXR compressions after my render but i think I was already in Zip.
For the context,
I had this issue more often with my old PC, making Cryptomatte almost unusable, but i had noticed that the pass was perfect when i tried to render on my mac laptop 
I thought it was hardware, but the new computer is from 2024 …
I’ll continue to investigate that problem, and will tell here if something is working …
What exactly do you mean by “the pass”? Cryptomatte uses several passes/layers. How can the image to pick masks constructed out of these layers be perfect? Who cares what it is as long as the masks work?.. Why are you talking about all Cryptomatte system as if it’s only a single image? Are you sure you are using Cryptomatte correctly?
Sorry for my bad English, i’m french.
I’m mean the cryptomatte in After Effect, or Nuke, etc … like on the Screenshots.
The passeS if you prefer.
When it’ works it’s full of color, and when it’s fucked up its black, white and grey.
Hello Martin,
Changing the compression of the of the EXR fixed the problem.
Thanks a lot for your time.
The problem is probably compatibility between After Effects and Blender.
I suspect there is a problem on Blender’s end here. I think there is a bug or even a few there in 4.0/4.1 versions. I did not have the time to investigate it enough for a bug report yet. There are problems with PIZ compression and compositing inside Blender as well and in some circumstances it plainly crashes renders which is pretty serious. It’s there with some of my complex interior scenes, but I couldn’t reproduce it with default scene yet, so not sure how it works exactly and which features trigger it.
