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View Full Version : Nasty render artifacts using Digital Confusion



dsol
06-27-2006, 06:31 AM
Hi chaps (and chapesses!),

I've been playing around with the Digital Confusion DOF image filter in LW8.5 and it generates lovely looking blurs.... with horrible nasty artifacts on top.

(example render attached)

Has anyone else come across this before and if so, how did you fix it? I'd really like to use DC instead of the inbuilt DOF in LW as it looks way more natural (with bokeh abherations and everything!)

Any suggestions gratefully received :)

Dan

Scazzino
06-28-2006, 03:02 PM
Double-check that you have disabled adaptive sampling under the camera's AA settings.

dsol
07-07-2006, 11:27 AM
This has turned out be one of those annoying inconsistent problems that seems to happen pretty much randomly. I tried rendering it again a few days ago and it it seemed to work better with fewer artifacts. Changing the type of lense artifact from "hexagon" to "cut disc" seemed to generate error-free renders. Sadly the DOF look isn't quite so nice to my eyes with the cut disc shapes.

I've compiled a page of test renders illustrating the level of corruption encountered depending on which lense shape you choose. Note the dark lines on the continents on some of the shots - this is also a render artifact. I think this is caused by the plugin not detecting the depth of the scene geometry correctly.

Anyway, maybe someone can work out what this means and why it's doing it?

toby
07-10-2006, 06:19 PM
That's not as bad as most of the artifacts I've seen with DC. Normally it looks like a kid took a black marker to each frame.

Since this looks more related to the geometry, and certain effects can make non-planars show up ( like refraction ) I'd go through the geometry and make sure it's perfect. And when you check for non-planars, make sure the threshold is very low, the default .5% is to much.

That said, I personnally don't ever expect DC to work, if you really need good DOF you should get Xdof. If it doesn't need to be that good, you can use LW's camera dof plus the 2d DOF plugin to soften the banding.