Selectively disable compositor effects?

In my animation, I’m using the compositor to put a glow effect on an object. However, there are many frames of the animation before the object is even seen, and the compositor is wasting time applying its effects to it.

Just wondering if there was a way to disable the compositor effects for a certain number of frames, or is there another way to achieve this?

If not, that’d be a cool thing to see implemented as a way to “manually optimize” rendering.

You can use an Input>Time node to restrict some operations to a specific frame range. How it might be used depends on your specific noodle set-up, but in general a frame range is set in the node and its output is piped to another node’s Factor or Size channel.

Keep in mind, though, that every node is evaluated for every frame, so this may not do what you want, and actually adds another node to the evaluation set. I’m not sure there’s any way to prevent a node’s evaluation short of deleting it from the noodle altogether. Even unconnected nodes are evaluated (though very quickly).

“Another way to achieve this” would be to render the frames where the Compositor is not needed with the “Do Composite” button disabled, then enable it and render the remaining frames. AFAIK this would be a manual operation unless you write a script to do it for you.

Understood. Thank you!