3Delight artifacts

wildstar

I'm pretty new to Daz and I wanted to make a street-tough scene - so I bought the Urban Sprawl 2 set. It always rendered black with the preset lights and the materials looked strangely flat when I tried to use a Sun-Sky environment light, so I switched to 3Delight from Iray - which I had been using exclusively. Great. Everything was going well, until I tried to do an upshot and the lighting was suddenly *very* harsh and there were all these weird artifacts on the character - like tessellation patterns or banding or something. At first I though there was some kind of strange UV tiling issue, but this only seems to happen from certain camera angles.

I *have* been getting errors during renders - 'DisplaceStrength' is not a parameter of shader 'dzdefaultshadow' - 'shader_Displacement', surface exceeded its bound by 0% - that sort of thing - but no errors that I could find pertaining to the character itself - and the renders had *seemed* fine until I changed camera angle. This problem seems to become evident when there is a dark background and the angle between camera and the brightest light is more than 90 degrees (if zero is directly from behind the camera).

Aside from the preset lights from the set - I have a key light with ray-traced shadows, a fill light with no shadows, a back light with no shadows, and an auxiliary light for the second character with ray-traced shadows. All are spotlights.

I've tried using the mapped shadows instead - tried fiddling with the shadow softness and all kinds of things. I'm new enough at this, I just don't know where to look online for help. I'm guessing there is some kind of conflict with materials that are geared for Iray or something? But I don't know how to tell - or what to do about it if that's true.

Can someone help or point me in the right direction?

Thanks!

unLight865

Hm, I'm still a bit lost in the shader/lighting business now and then (especially the intensity control of IRay-lights for me often doesn't seem to work at all), but I'd guess you'd need to find an 3De-Shader in your library, and then apply that to your figure.

If you have IRay-specific lights in your scene, you'll also need to replace those by 3De-ones.

Hope that helps...

 

P.S.: Shaders aren't the same as materials, so you shouldn't loose texture information/setup.

(Sorry - forget that last bit about textures - as the textures are selected as a setting for the shader, they might well get reset... So better remember texture filenames + path, so you can set them for the 'new' shader later on; although if you're lucky they'll be in the quickselect-list too)

wildstar

Thanks so much for your reply unLight865.

As far as I can tell all the lights are 3DE compliant - that is, none of them have the photometrics option on.

I cannot find *anything* that looks like a 3DE shader - and I can't tell which shader is attached to any object or part of an object in the scene either. I'm in the surfaces tab - and there seems to be no information about any of it. I see a list of shaders, but there is no information about what they are. They *look* just like materials. If I could just find out if the character is using an Iray shader - maybe that's the problem - but I can't even tell - it's SO frustrating!

wildstar

I think I've got it sort of figured out.

The problem seems to be caused by the combination of sub-surface scattering with the 3Delight rendering engine.

If I turn the sub-surface scattering off - then those strange mosaic-tessellation patterns and the bright points disappear.

unLight865

Ok, I didn't look into subsurface much yet... And sorry my explanation wasn't clear. ( good you found a solution yourself )

As for shaders - there should be several in your content library - the surfaces-tab on the other hand is where you set a shaders OPTIONS, not the shader itself.

 

To apply a shader, select in the surfaces tab the surface you want to apply a different shader to - then go to the content library tab ( maybe smart content tab works too, but I usually don't use it ) , find a shader there ( it has a folder called 'shader presets' and some other - just look into those ) and then double-click on the shader.

As for how to see if its an 3De- or Iray-Shader:  Well, theres a folder called Nvidia or Iray, the shaders in there are very likely Iray ones. Other than that I can only guess, too.

 

Hope this clarifies a bit... :)

 

 

[edit:  spelling correction]