I was wondering, if it’s possible to disable Blender from rendering the main output that appears in the panel. I’ve set up 4 different scenes to render in the compositor and works perfectly, but Blender also renders out the main file output that’s set up in the output properties panel of the scene. I’ve tried to set up a path that doesn’t exist, but then on the second frame on the animation it bugs out “says path doesn’t exist” and stops the whole rendering. I would have assumed that, if I set up a file output for the scene in the compositor it would overwrite and take over the main one from the output properties panel, but it doesn’t and I don’t know how to turn it off. Now of course I can set up a trash folder and put those images there and delete them after the render, but: 1. I like to keep things tidy. 2 I think this ads ~1 second of processing to the rendering, which I would love to eliminate. I can’t find anything online about this, the compositing tool seems to be a rabbit hole on youtube and google, I can never find the things I’m looking for Thanks in advance!
Oh and also I’ve disabled the rendering of the view layer in which I set up the compositor node, but still it renders and exports blank transparent images. There’s just no turning off this things is it?
Rendering anything out of Blender is often a path to frustration. What could be very simple is often aggravating annoying compared to other 3d applications.
I recommend a proper render manager to get rid of some of the frustrations, and the ability to set up & render multiple render layers at once.
But what you’re describing is the default behavior.
It will render/save the image first, and then render the result again through the compositor setup to a file named accordingly in the output node.
In this other case it will only render at Output Node path. In this case I set a EXR multilayer, so it will be a single file, if is another format like JPG or PNG, Blender will render one image per render pass at File Output Node path.
I’m bringing this back from the dead because I’m having the same issue and the solution posted by @lucas.coutin doesn’t work. Even if there’s only a File Output node on the compositor, Blender is still rendering an extra set of images based on the main output. How can this be avoided?
That’s because it’s not possible (not even if you run the operator bpy.ops.render.render() from the console with animation=True, write_still=False). Blender always renders something to the render output. Devs seem to know about it. The issue is still open, so maybe someone will fix it in the future. But it’s not a big deal since you can always just use the render output and only use File Output nodes if you need additional output. There is not much difference… If you only need custom layers in a Multilayer EXR that you cannot do with composite node, just set the render output to some dummy folder and have the composite node connected to nothing. You can use EXR with PIZ or DWAA codec for fast saving with very small file sizes for all black image. PIZ is faster, DWAA is smaller. Both seem to be better for this than other formats.
I don’t really think posting your frustrations is very helpful. Also the caricature does not seem to be relevant at all to be honest. Nobody has offered a solution that would be fundamental for someone struggling with some job, instead you seem to be nagging people to do work and give you a solution to a minor problem. This is not some commercial software where you can angrily complain to support and one of the lead developers is probably not there to entertain you and deal with “unhappy customer”… Did you notice the quotes? That’s because you are not a customer - the software is free. That changes the context and should probably change the tone one communicates with the developers if they want to achieve something …at least in my opinion.
Last Brecht’s comment from 4 years ago on the issue in the bug report says:
We haven’t agreed on an exact UI design for this yet, it’s not really ready to be picked up by someone.
You could suggest possible solutions to this. But hold your horses, the suggestions need to be good and make sense and match Blender’s UI principles and philosophy. How should this work? Should render just skip writing to render output if there is no Composite node? Or should Composite node just be changed so it has functionality to write custom Multilayer EXR layers?.. What happens to the functionality when Composite node just takes all the enabled passes of the render when you simply plug one input to it?.. How is that going to affect backwards compatibility with existing files for thousands of people? If this is a breaking change, should it maybe be implemented with version 4?.. Developers need to start talking about these things, not about your hurt feelings.
The first post was an honest question. I am honestly interested to understand your perspective there.
The judgement is because you are using wrong approach to achieve any results. Whatever reason is that Brecht deleted your post, you failed in communication with him. You will definitely not reach any results if you piss the devs off, especially Brecht. So yeah, you are definitely totally wrong there - no question there.
I am interested why this bug causes you great inconvenience. This is a bug and it should be fixed in my opinion and by the way the task is open, so the devs also want to fix it apparently. That is one matter. The other part of my message is that complaining, posting irrelevant caricatures, nagging and pissing the devs off will not help.
So I agree to you that there is an issue and it should be fixed. I disagree with your idea to go and complain about it in a disrespectful manner towards the devs. In this sense you are very wrong if your goal is to encourage them to fix the issue. I also agree to what you quoted from the chat:
… however that doesn’t mean other outlets like devtalk or the tracker should be the outlet for them[feature requests] or the frustration you feel …
In any case. Why does this bug cause you such great inconvenience?
I’m pretty sure I don’t understand exactly how all these tools are interconnected within Blender, so I might be wrong. But how about a checkmark that becomes available only if you set up some render layers in the compositor. Checkmark is on by default, if you turn it off it won’t force render the main layer, if nothing is set up in the compositor it’s automatically on by default. How does this sound?
My case was that I had to render out multiple thousands of different images through the compositing node. The actual images were around 2 seconds to render and Blender also added an extra 1 second processing by rendering out full black jpgs (full black JPGs had the fastest processing to render) for the main layer which I didn’t need. So this added an extra 50% rendering time for me which resulted in multiple hours of extra rendering time by the end of the project.
Yeah, that’s a good question. I need to open up the project and check because I forgot, but there was a reason for sure. I will let you know, if I figure it out.
As far as I know, the only problem is that Compositing node does not have Multilayer EXR layer inputs, so you cannot choose what layers to write without File Output node, but else than that anything you need to do should be possible to achieve.
Thanks in advance!
