Levels on a standard layer affecting the layers underneath

[andrzejgoulding]

I have two layers.

The top layer is a "screen" layer and I have a levels effect applied to it.

When I adjust the black levels (the left-most pin on the graph) on the top layer it is affecting the values of the layer underneath as if it was an adjustment layer. That shouldn't be the way this works as it's only applied to the top layer.

It makes it very hard to use the levels effect properly in this scenario.

[Vishu_Aggarwal]

Can you make a video and post here or share the screenshots. Do you mean Top layer is set Screen in the Blending mode settings?

[kirkeric]

I'm trying to understand this. You set a top layer to "Screen"?  I would expect any layer on top that is set to screen to affect the layer beneath it.  By setting to screen (if that's what I think it is), it is already affecting the bottom layer.

Can you elaborate?

Eric

[Dave_LaRonde]

BritMorph  wrote

I have two layers.

The top layer is a "screen" layer and I have a levels effect applied to it.

When I adjust the black levels (the left-most pin on the graph) on the top layer it is affecting the values of the layer underneath as if it was an adjustment layer. That shouldn't be the way this works as it's only applied to the top layer.

Wrongo!  That is PRECISELY how it should work.  Something tells me you have a little reading-up to do on AE Blend Modes.

[andrzejgoulding]

But that doesn't sound right at all.

Screen layers basically only apply the "light" areas of an image to the layer underneath right? I'm using the levels to adjust the top layer to refine the amount of dark and light which I would then expect for just the light areas to be projected onto the layer below.

But what's happening is that by changing the levels on the top layer it's as if the levels (ie. the black point) is adjusting the layer underneath. This is what I would expect from an adjustment layer. Putting an effect onto a regular layer would surely apply the effects to the layer BEFORE then applying the blend mode?

Levels Issue - YouTube

Here is what is happening.

EDIT: If I do the same with a curves instead of a levels it's fine so it's not a misunderstanding of the blend mode.

[Warren Heaton]

Nest the front layer into its own Comp and adjust the Levels Effect on the Layer inside the nested Comp.  The Blending Mode for the Layer should be Normal inside the nested Comp as well.

Back in the containing Comp, set the Blending Mode to Screen.

You should be good to go.

[andrzejgoulding]

Absolutely that is a workaround, and is what I've already had to do. If however you use a curves effect or a brightness effect to try and achieve a similar result (upping the black levels of that layer) the layer underneath isn't affected in that strange way.

To me it looks like a bug in the Levels effect, it simply shouldn't be effectively changing the levels of the layer below. It should be changing the levels of the layer it's on and only after that has been processed should the screen layer blend mode transfer the light areas onto the layer below.

I would have submitted an actual bug report to Adobe but they seem to have changed the way that is done too. I click on the bug report link and it went to a broken webpage.

[Warren Heaton]

It’s just a rending order issue.  Blending Modes are rendered first while Effects are rendered second.

[andrzejgoulding]

So how come the curves effect and brightness/contrast effect doesn't do the same thing?

[Roei Tzoref]

I would have submitted an actual bug report to Adobe but they seem to have changed the way that is done too. I click on the bug report link and it went to a broken webpage.

file it here:
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