Guidance when sculpting with a alpha brush to minimize baking issues

[Jake_See]

Hello people! My first community post on gamedev!

I am on the blender course video where we design an orc. I have reached the stage where we are baking normal and cavity maps. I run into a problem with cavity map which apparently is common among beginners: there are dark patches in the map where the low poly model is underneath the high poly model surface.

In my case, this happens around the skin patches sculpted with alpha brush in using the Draw tool. It seems that my skin patches are too dense and too elevated for the low poly model to project the cavity data. Is my analysis correct?

Is there a guidance as to what would be the ideal thickness of these skin patches to avoid baking problems? Or is there a magic formula to determine what the bake settings should be?

Thanks!

[NP5]

Bake using the Extrusion factor, next to the Ray Distance one in the bake panel. (It was put in after the lectures were made.)

Set extrusion to 0.002 As a first test, these numbers will vary by model and HP/LP fit.
Set Max Ray Distance, you can probably leave it at zero. But again it is a number that may need adjusting to your use case.

Play with these numbers until you get a good result. This bit is not a matter of using X and Y numbers as every model varies. It often needs several tries to find a good pair of values.

Welcome to the forum!