Increaced detail settings makes errors worse!

[cyphyr]

Hi Guys
A bit of an oddity here.
I submitted an animation render to our farm with detail settings at 0.7, AA 5, detail blending 1 and Ray detail region padding (Detail in camera) set to 1.0 and there was a small amount of shadow popping (the sun is behind the camera) and pixel creep (across a near vertical cliff). Unfortunate but not unsupprising. So I upped my settings to 0.8, AA 6, detail blending 1 and Ray detail region padding (Detail in camera) set to 0.5 thinking this would be enough to create a completely smooth animation. But the reverse has happened, the shadow popping although not so extreme is no over the entire length of the animation and the pixel creep is as before. SO my question is can an increase in detail setting (across the board) give more errors as there are more accuracy to deal with?
cheers
Richard

[Seth]

I think it is because you decreased the ray detail region padding that you have more shadow popping, not because you increased the detail.

[Tangled-Universe]

I tend to think so too...nonetheless this is an example of why it's sometimes best to change only 1 thing at a time, but deadlines don't always allow for that of course.
If the lightsource and shadows are from behind the camera you might consider exploring the bottom function of the render subdiv settings node, which is only available in current alpha versions.
First I'd revert back to the ray detail region padding with det 0.8 and AA6 to deduce the problem stepwise.

I understand your doubt by the way, since you could consider lower detail settings as a more "averaged result" of the whole scene. However, those averaged results are still based on inaccurate/faster calculations and therefore likely result in more inter-frame differences.

[Hetzen]

Hi Richard

You could use a distance shader which creates a gradient behind the camera to flatten any displacements gradually, therefore eliminating anything casting a shadow behind the camera in frame. I know this would not work on all image sequences. But maybe worth investigating.

Cheers

Jon

[Hetzen]

Here you go. Try this. You'll need to plug it in after any major displacements, and will not really work with populations, I guess something similar could work to drive the opacity of your models.

Cheers

Jon

[Tangled-Universe]

Here you go. Try this. You'll need to plug it in after any major displacements, and will not really work with populations, I guess something similar could work to drive the opacity of your models.

Cheers

Jon

If it works for terrain it should also work for populations I'd think? Hook the distance shader trick into the density shader input and it should work in relatively similar fashion I'd guess?

[Hetzen]

The only thing Martin, is that a tree will either be on or off if you use it for the population mask, therefore getting shadow pops as trees disappear. Using a distance shader for your material opacity, will at least disolve them out.

[Tangled-Universe]

I see what you mean...you're right that this doesn't work at the moment, since opacity isn't working fully yet.

At the moment I would stick to my own suggestion of reverting back to the ray detail region padding, test if that works and if not then trying that new parameter in the render subdiv node.

[cyphyr]

Hi guys thanks for your thoughts.
I miss-typed my first post, it should have read the reverse, ie, Ray detail region padding (Detail in camera) set to 0.5 firstly and then to Ray detail region padding (Detail in camera) set to 1.0 on the seccond attempt.
The idea of a flatten terrain may help somewhat, I'll give it a go.
The scene did have a hell of a lot of Fake stones in it, never a good way to start a day!
Cheers
Richard