KeyShot Forum

Technical discussions => Rendering => Topic started by: figure1a on June 12, 2020, 05:03:09 PM

Title: Noise is different in render layer than RGB layer
Post by: figure1a on June 12, 2020, 05:03:09 PM
Is this a know thing or "feature" I can turn off? See attached images. One is from the RGB layer. One is from the render layer. There is a ton of noise in the render layer.
Title: Re: Noise is different in render layer than RGB layer
Post by: djnoone on June 15, 2020, 12:24:03 PM
Only the composit (RGB) gets denoising by default.
Any other pass is kind of a raw straight out render result.
This is also true for all other Image style settings - passes does not get any of the post-production result (glow, aberration, Vigenette etc.)

The idea is - if you are using passes - you will denoise them, blend them, filter them in your composition software.
Title: Re: Noise is different in render layer than RGB layer
Post by: figure1a on June 15, 2020, 01:34:27 PM
Quote from: djnoone on June 15, 2020, 12:24:03 PM
Only the composit (RGB) gets denoising by default.
Any other pass is kind of a raw straight out render result.
This is also true for all other Image style settings - passes does not get any of the post-production result (glow, aberration, Vigenette etc.)

The idea is - if you are using passes - you will denoise them, blend them, filter them in your composition software.
Got it. Kind of figuring out that render layers are pretty much useless. The noise issue. And also the matte always puts an extra pixel or two around it leaving a colored fringe. Seems like it's just easier to remask stuff using the clown layer.
Title: Re: Noise is different in render layer than RGB layer
Post by: djnoone on June 15, 2020, 02:47:44 PM
The Layers are useful but in other ways.
Usually in scenario with basic lighting/shading (straight objects on bright lights, not complex scenes)
The fringing of the edges is removable in Photoshop -> Layer -> Matting -> Defringe.

Again - on straight objects.

In photo-realistic scenes the matting of the objects should be dependable on all the elements present, not "cut out" as layers.
Title: Re: Noise is different in render layer than RGB layer
Post by: andy.engelkemier on June 18, 2020, 10:53:10 AM
Ha, this is exactly WHY I'll use render layers now.
Often times denoise kills your smaller details in textures. Now I'll just select Everything and put it on a render layer. Boom, two renders without having to resubmit. One denoised, and one regular noise.

Also, defringe doesn't really work if you use DOF. So that part sucks. I mean, it gets rid of the darker line around it, but the render layer under heavy blur doesn't look right, so I have to just paint a mask for that over the original render.
Title: Re: Noise is different in render layer than RGB layer
Post by: Esben Oxholm on June 19, 2020, 01:46:29 AM
Quote from: andy.engelkemier on June 18, 2020, 10:53:10 AM
Now I'll just select Everything and put it on a render layer. Boom, two renders without having to resubmit. One denoised, and one regular noise.

Haven't tested it, but sounds like a super useful workaround! Thanks for sharing.