Getting Rid of Shadow Grain and Grunge in DAZ Studio 4.5. Renders

cafedelic

Got grainy, dirty, splotchy -- and just plain butt-ugly -- shadows in your DAZ Studio 4.5 renders?

It took me many hours of frustrating experimentation to sort this out. So, I thought I would share...

There's no telling why an unlucky few are afflicted by shadow grunge. The most plausible explanation I've heard is an incompatibility with certain graphics cards --especially certain ATI models. For what it's worth, I'm using an ATI Radeon HD 4870 in a Mac Pro Tower and my shadow areas looked like the Black Plague.

As for the cure, the first place I looked was in the Advanced Render pane. I tested anything that seemed to have anything to do with shadow rendering -- especially Ray Trace Depth, Shadow Samples and Shading Rate. Nothing helped.

In one of the Forums I saw where the Ubermeister concedes that the UberEnvironment can cause graiyn shadows and recommends setting the Shading Rate to 1.0.

I'd already tried lowering my Advanced Render Shading Rate, but I tried it again. No surprise, it didn't work.

Then I discovered there is a separate Shading Rate parameter setting for the UberEnvironment. When I lowered it from 8 to 1, I saw an almost imperceptible improvement.

After that I tried creating my own Light Presets. Whether they included the UberEnvironment or not, none of them had Shadow Grunge.

The problem is that there are other things I'd rather be doing than fiddling with lights. Lots of things.

At this point, I compared the settings on my light parameters to the settings used by some of my favorite Third-Party Light Presets.

The cause of my Black Plague, it turned out, was a setting near the bottom of the parameter pane called SHADOW SOFTNESS which can be found on both Distant Lights and Spotlights.

Not, surprisingly, people who make light presets, crank this setting up to create nice, even lighting with diffuse shadows. Unfortunately, this setting turned out to be the cause of at least 90 percent of my render grunge.

So, there you have it. If you, too, are suffering from the Render Grunge Plague, try turning off the SHADOW SETTING on your Distant Lights and Spotlights.

It works like a charm for me!

Szark

cafedelic said:

The problem is that there are other things I'd rather be doing than fiddling with lights. Lots of things.

This how a lot of us here learnt and it is a good way to learn IMHO.

Anyways Shadow Softness is only good for giving the shadow a soft edge as opposed to a hard edge and has no effect on quality..

My question is were you using Deep Shadow Mapping or RayTraced Shadows? As the thing is with Deep Shadow Maps being a map at a resolution of 1024 x1024 so if your image is bigger you will 9 times out of 10 have shadow issues. Ray Traced Shadows may take longer to render but at least you get good accurate shadows. Also in the Advanced Render Settings there is a Shadow Samples setting..Increasing this to say 24 can help with shadows too.

When using UberEnviroment2 the best setting to use is either Occlusion with Soft Shadows or the more advanced setting of Indirect Lighting with Soft Shadows as you will never get a HDRI map to create proper direction shadows that a light/lamp or the sun would make. Here is a great thread about UberEnviroment2 * Learning UberEnvironment 2

Also the Shading Rate in the Advanced Render Settings should be at a value of 0.20 - 0.10 when using UE2. Max Ray Trace Depth 1 to start. If using any Ray Trace function like Refraction or multiple Reflections then this needs increasing no mater what light set you are using.

cafedelic

Pete,

Thanks for the further explanation. I was using Ray Traced Shadows.

I think one of the problems newbies like me have with the 3D Delight Advanced Render is that there are so many potential adjustments that isolating the cause of a problem can be a monumental task.

It's the same with Poser, of course, only I'm more familiar with the way Firefly works.

Thanks again.

Szark

If you break it down you soon learn what to adjust.

Example Uber Enviroment gives you Ambient Occlusion so if you see grain in those areas then adjust UE2. If you see grain on the edges of the shadows from the Key light then increasing Shadow Samples and lowering the shading rate will help.

If you see Grain on the egdes of items then increasing the Anti Alias setting of both Pixel Samples X and Y will fix that. This is a valuable tip when using DOF. The more DOF the more you increase Pixel Samples X and Y. Max is 16 which I often have to use when doing heavy DOF.

But the thing is if you are only using the standard lights then all the Advanced Render Settings can be set to a lower quality when not using UE2, Area Lighting etc.