Newbie Question: What is shadow softness?

behansen

On DAZ studio, I have two options for shadow, whether it be raytraced or deep shadows: Shadow softness and shadow bias. What is shadow softness? is it basically how hard or intense a shadow is in terms of graduation between light and dark tones in a given area or is it something else entirely? Does it affect render times significantly?

jerriecan

You pretty much got it right - 0% softness gives a sharply defined shadow like on a bright sunny day, 100% softness gives pretty much no cast shadow at all. I've never seen it measurably affect render time.

SpottedKitty

I think it's shadow bias that affects render time. I can't remember the technical terms, but it's a measure of how close the shadow-casting object can get to the shadowed object. Too close and the shadow will suddenly cut off — the effect is most obvious on the edges of loose clothes that dip in close to the figure wearing them here and there. A lower bias value gives more accurate shadows but takes longer to calculate.

Novica

Kinda curious- what setting is "too low" or "normal?"

SpottedKitty

The only way to find out, really, is to render. The Bias value seems to be in centimetres, like all other D|S distance measurements. So the edge of e.g. a sleeve curling in to just a few millimetres from the arm inside will be affected if you leave the Bias at what I think is its default value for a new light, 1cm. It's the usual tradeoff — go for good shadow fidelity and accuracy, or a not-too-long render time, you have to strike a balance between them. FWIW, my usual starting point for experimenting with Bias values is 0.1 or 0.2.

Novica

Appreciate your input SpottedKitty. I have pretty much left settings alone because it's so darned overwhelming- except for the render settings since Adam put out that guideline post (I am pretty sure it was Adam) But even then, I don't know what the settings do, lol! I'll try your settings on my more complicated/artwork renders.