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Burndog
10-30-2013, 03:07 PM
Hello,
I have a reflection and on final render it sparkles. Increasing the anti-alias passes reduces the sparkling pixels but is there a better way without having to use a blur in Post (FCPX , After Effects ext)?

Here is the render :
http://sgdesign.com/temp/blur.mov

Tranimatronic
10-30-2013, 03:10 PM
http://forums.newtek.com/showthread.php?138274-Glitter-in-skin-shader
are you using GI? if so take a quick look at this thread. Increase your RPE
If not try increasing your shading/lighting samples

jwiede
10-30-2013, 03:10 PM
Hmm, that's a bit odd, do you have dithering turned on?

Tranimatronic
10-30-2013, 03:15 PM
also yout minumum samples are more than your maximum samples. Not sure if that will make any difference?

Burndog
10-30-2013, 03:59 PM
No GI
Dithering is also not turned on...
min and max samples does not effect the output as initially the min was 4 which showed even worse glittering

Burndog
10-30-2013, 05:30 PM
Here's the files in case anyone wants to see if it is a system based issue. LW 11.6

JoePoe
10-30-2013, 05:51 PM
Well, I brought this into 9.6..... so, who knows what got changed. My renders are..... different.

But in the scene I'm looking at you DO have GI on at 100%.
If that's the case don't you need to have both the Cache and Animation boxes checked?

Just thinking out load.....

XswampyX
10-30-2013, 06:25 PM
It's a really difficult one for LW to render as you are only rendering the reflections. The surface won't show GI, lighting, shadows.... anything else!
You have 2 small boxes to render on your surface and the rest of your scene is black/blank so you only have a very small chance of a ray actually hitting one of the boxes and showing in the final render.
Put your minimum samples to 16, maximum samples to 256, threshold to 0.001 and over sample to 0.5.

Netvudu
10-30-2013, 06:29 PM
Minimum 14, maximum 9 and threshold 0.0? Something´s fishy there...weirdest values ever.

Tobian
10-30-2013, 06:31 PM
That's just down to a lack of AA really.

There's a number of things to do.

1) increase your 'shading samples' in the render globals, render tab. 1, is the new default, and it's too low, especially for scenes like this.

2) use adaptive sampling, to clean it up some more. Your max samples being lower than your min is silly :p

3) don't use dispersion, it's not really doing anything, (in this scene) and it triples render times for a given shader.

Lightwave changed the way it samples reflection blur to be more realistic. I am not sure what your gradient is supposed to be doing, but you shouldn't need incidence tricks to smear the reflection blur, as you would in 9.x / 10.x and earlier. 11.x does it much better, so sadly JoePoe, it will look different to you. Sadly it means that at glancing angles you get more noise, as it has to put more effort into those. It's possible to do post-tricks, but it's never very good, especially where you have contact-hits

Burndog
10-31-2013, 10:32 AM
Put your minimum samples to 16, maximum samples to 256, threshold to 0.001 and over sample to 0.5.

These settings seem to have really smoothed out the reflection (albeit at a render time cost). Rendering the animation now and will check to see if any sparkling is in effect when complete.

Burndog
10-31-2013, 12:43 PM
Thanks for the advise folks!
Went with min samples of 16 max 80 and no GI. Render times reasonable and results are excellent.

Sensei
10-31-2013, 09:03 PM
Burndog, watch mine video tutorials how to control reflections:
http://www.youtube.com/watch?v=WjvUxRnNcak
http://www.youtube.com/watch?v=nP425jM1oGM

Burndog
11-01-2013, 07:10 AM
Sensei, thanks for the links and I did look at those vids prior to setting up the reflection as it's what prompted me to use a gradient