Shadow pass

[ramone163]

I have scene with Sun Light, and I want to save object+shadow on transparency background.
How to render clean shadow without AO?

[paride4331]

Hi ramone163,
you have to use "alpha channel" Kernel setting and "shadow catcher" for cast shadows (in spread material).
About those concentric circles, check your scale units and the value of epsilon-ray.
The ray epsilon is the distance to offset new rays so they do not intersect with the originating_server geometry.
If the scale of your scene is too large, precision artifacts in the form of concentric circles may appear.
In That case, Increasing the ray can make epsilon These artifacts disappear.
In general, using high density meshes, the default "Ray Epsilon" of 0001 can be used. E.g. A "rayepsilon" of 0075 = 7.5cms.
Regards
Paride

[ramone163]

"alpha channel" + "shadow catcher"

[paride4331]

Hi ramone163,
there may be a minimum of gray with AO 0.01 but your seems too much.
have you turned off the vignetting?
Paride

[ramone163]

Vignetting is OFF.
How to make AO 0.0?
And why AO in SHADOW pass also?

Hi ramone163,
there may be a minimum of gray with AO 0.01 but your seems too much.
have you turned off the vignetting?
Paride

[paride4331]

Hi ramone163,
0,01 is max in 3dsMax plugin and in Octane SA is 0 but this issue is like 0,01.
This issue you would have with shadow and black shadow pass too.
Perhaps new shadow pass (Octane SDK 3.06 Test 4) could solve it, but 3dsMax plugin is 4.30 - 3.05 now, and 4.31 - 3.06 (TEST) is SDK Test 3.
Paride

[ramone163]

In Octane SA 3.06 Test 4 new shadow pass works fine, but not in 3ds max.
Hope they fix it.