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WirePeople
08-05-2015, 09:30 AM
Forgive me if this has a really obvious solution, I just upgraded to LW 2015 from v10.1 and much has changed. A simple render of a cable in image 1. The black jacket has a transparency envelope to show the white insulation layer beneath. But when the outer jacket is 100% transparent I still see some odd noise on the insulation below. (image 2) No radiosity being used, I've excluded the black jacket from the V-stack to see if that helps. What am I overlooking? (This same scene rendered in LW ver 10.1 does not show this noise, so clearly there's some setting I need to adjust, I just don't know where to start.)

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Sensei
08-05-2015, 10:25 AM
New LightWave has unified sampling introduced.
Completely different method of doing anti-aliasing,
and receiving soft shadows.

WirePeople
08-05-2015, 10:56 AM
So, what would be the best approach to eliminating the noise in that area?

Sensei
08-05-2015, 11:20 AM
See if increasing Minimum Samples in Camera Properties helps.

Dexter2999
08-05-2015, 11:28 AM
This is intended to be helpful. Please don't take this the wrong way.

Sometimes we get a bit caught up in trying to do everything inside the software.
The "best approach" can be the one that negates the issue in the finished product and meets your deadline.
Not the one that corrects your issue inside the software.

I would suggest removing the black outer jacket altogether and do a render without those polys, Then, in your editing software, do a dissolve between the image with the jacket and the image without the jacket. (Feel free to replace "image" with "sequence"...still works.)

WirePeople
08-05-2015, 11:35 AM
An excellent point. I was in the process of just comping this in AE as a workaround, but I realize I still need to understand how to work around this situation for the long run. Sensei's suggestion of the minimum samples in Camera Properties was just the ticket, so hopefully moving forward I know where to tweak if I run into something that requires me to stay within LW. I have a lot of catching up to do with LW 2015, and I appreciate the guidance of this forum.

Sensei
08-05-2015, 11:50 AM
BTW, if you enveloped transparency (dissolved? these are two different things.. Dissolve requires splitting object to layers)
pay attention to method of interpolation!
If you don't set it to linear, default smooth curve might be going slightly UP, exceeding 100%, and so the same at end.

RebelHill
08-05-2015, 11:53 AM
https://www.youtube.com/watch?v=UgNB9tZWUmM&list=PL8A1C0DB658775A63&index=1

WirePeople
08-05-2015, 12:08 PM
Thankyou, Sensei, fortunately I did have the interpolation at linear in the graph editor. The black jacket is an object of itself, as it slides onto the insulation layer; the transparency envelope in the surface editor was a fast way to make it reveal the object beneath. That's what happens when I get stuck in the same old way of doing things... Thanks to your help, and the particularly relevant tutorial from RebelHill, I know where to direct my learning focus.