Author Topic: Shadow pass comping  (Read 4901 times)

2019-02-21, 00:00:18

actrask

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What is the best way to comp in a CShading_Shadows pass? None of the blending modes seem to be doing the trick in Photoshop (32bit exr).

2019-02-21, 00:44:35
Reply #1

fraine7

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I rarely use the shadow pass these days but I believe it should first be inverted. Then you can ‘multiply’ it in your comp

2019-02-21, 14:29:50
Reply #2

TomG

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Yes, it would need inverting. As on this page https://corona-renderer.com/wiki/render_elements

"Shows the shadows (energy subtracted from the image due to shadow ray occlusion). This is the complement to the beauty pass, showing white where there are black shadows. If this pass is linearly added to the beauty pass, it negates the visible shadows. Note that currently the shadows from environment lighting are always shown, resulting in a washed-out pass in typical interior renders."
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2019-02-21, 14:32:35
Reply #3

maru

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The shadows pass can be used for various things. Here is how to remove shadows from the image using it:
-make sure no tone mapping is used (highlight compression, saturation, contrast, etc. - all must be set to defaults, except exposure, it can be set to any value)
-make sure you save in 32-bit depth
-open your files in PS
-set beauty as background, shadow pass above it
-use "Linear dodge (add)" blending mode
-your image should then become "flat", without shadows

Likewise, to amplify the shadows, you should use other type of blending. For example "multiply".
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2019-02-21, 16:54:05
Reply #4

actrask

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Maru, I tried your method in Photoshop but the comp goes completely white. To get it looking right I have to set the opacity of the shadow layer to 1%, then put it in a group and set that group to 7% opacity. Is this a limitation of Photoshop's 32-bit functionality?

Speaking of Photoshop limitations, why doesn't invert work in 32-bit mode? Fraine7, what program are you comping with?

2019-03-04, 19:33:41
Reply #5

fraine7

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Maru, I tried your method in Photoshop but the comp goes completely white. To get it looking right I have to set the opacity of the shadow layer to 1%, then put it in a group and set that group to 7% opacity. Is this a limitation of Photoshop's 32-bit functionality?

Speaking of Photoshop limitations, why doesn't invert work in 32-bit mode? Fraine7, what program are you comping with?

Hi actrask, I'm using Photoshop - invert is only available in 16-bit you are correct. I rarely use render elements in my comping these days, if I were to go back to element comping I would have to use After Effects as I used to do.