Merge or combine multiple adjustment layers / curves - After Effects

[DustyBin....]

Is it possible to merge multiple Curves adjustments into one single Curves layer.

Say, one Curves layer has adjustments on the Red channel, another adjustment layer on the Blue Channel and a third adjustemnt layer on the Main Channel.

Would it be possible to merge those into a combined single Curves adjustment.

Or is that something I would have to do manually and by "eye" to just add those curves altogther by creating a new curves adjustment layer?

Is there any copy and paste functions I'm not aware of to help with that, without each pasting overwriting the previous pasting?

I hope that makes sense. The aim is to reduce render times for projects with mutiple curves adjustents.

[Mylenium]

The render times likely wouldn't change much even if you could merge them. Not how it works and you're operating on wrong assumptions here. That said, it's not possible. Unlike Photoshop there's no way to convert multiple adjustments into a LUT or such. If there are any performance issues they are most definitely unrelated to this effect and even if they were, investing in a more optimized third-party effect would probably be the better option.

Mylenium 

[Rick Gerard]

Unless you have a mask on an adjustment layer, I can think of no reason to have more than one at the top of a composition. In about 90% of the compositions I have helped troubleshoot since adjustment layers came out, using an Adjustment layer instead of just putting the effect on a layer overly complicates a comp and wastes time. The only real practical reason for an adjustment layer is to apply an effect like color correction to all layers below the adjustment layer.

That said, nothing prevents you from putting more than one copy of most effects on the same layer. Curves have Red, Green, Blue, and Alpha adjustments, as well as a global adjustment for RGB. If you need more than one Curves on a layer, it's entirely possible but the effects are cumulative. 

If you want to modify only the red channel, then you want to modify only the green channel, then you want to combine both results using something like a blend mode or other effect, you'll need two copies of the footage layer and a blend mode or effect that can sample more than one layers. 

Tell us exactly what you are trying to accomplish, and share screenshots. If we know what you are trying to do, we can probably help you clean up your workflow or create the effect you are after. 

[DustyBin....]

Thanks both for the quick replies.

Yes I agree it's bad practice having multiple curves adjustment layers.

I can rectify this by simply creating a new layer and manually building a curves adjustment that is pretty close and matches.

They are basically all perfroming a kind of colour grading and could be done afterwards in a separate render, or post edit render.

I really just wondered if it was possible at all using some kind of keyboard shortcut or action.

Absolutely no problem though.

Thanks both for your help again 🙂