Light through clear coloured plastic - Help

carlos@the-hubb.co.uk · September 03, 2013, 02:45:30 AM

Hi all, I am getting an odd effect when putting a light (Any), passing through clear coloured plastic; it's like sprayed paint all over. See image attached.
Does anybody know why? There is supposed to be an LED strip on the inside of the red part, which is clear tinted plastic, but when assigning any kind of light, either spot or area, the render shows an odd effect. I have tried different materials and even caustics on and off but the spray still comes out on the renders.

Any help is appreciated
Thank you
Carlos

maymay · September 04, 2013, 12:36:41 PM

Can you share the BIP file? Or at least a portion of it that demonstrates this problem?

Ruckus · September 04, 2013, 01:13:35 PM

Is that top border of your base supposed to be black? (I suspect not, since some light is getting through on the right side.) If it is clear (or clear tinted) then go to Project-->Settings and turn up your ray bounces.

I was playing around with a "glass engine" recently and I had to go up to almost 40 bounces before I stopped getting black. I doubt you will need nearly that many for this project. Try 12. And the number of bounces needed may be different depending on the viewing angle.

This might also help the dots, which I suspect are just light getting out of your base in limited places.

rkulshrestha · September 05, 2013, 11:09:37 PM

Hi

Maybe your surfaces are touching each other. Isolate the surfaces microscopically and the colors should come through. Or atleast you might have better control.

Shivani

Speedster · September 06, 2013, 05:45:56 AM

QuoteIsolate the surfaces microscopically and the colors should come through.

You can usually isolate (separate) surface directly in KeyShot by simply scaling one or more components, like .998 or so. No visible impact, but often solves the problem without going back to the CAD model.
Bill G

PhilippeV8 · September 10, 2013, 12:11:45 AM

Try with "Ground Illumination" turned off ... does that help any ?

carlos@the-hubb.co.uk · September 10, 2013, 01:23:52 AM

Quote from: PhilippeV8 on September 10, 2013, 12:11:45 AM
Try with "Ground Illumination" turned off ... does that help any ?

Thank you Phillippe. It does reduce the amount of pollution but not completely. I changed materials for glass in different densities to see if that combined with your suggestion could make a difference but I had no luck.

I am starting to think that it could be my graphics card ?? I have an NVIDIA Quadro 3000M

Speedster · September 10, 2013, 05:42:16 AM

QuoteI am starting to think that it could be my graphics card ??

KeyShot doesn't care what graphics card you use, as it runs only on CPU's. So something else is funky.
Bill G

PhilippeV8 · September 10, 2013, 07:46:42 AM

What if you change your "solid glass" or "glass" material for "translucent plastic ?

carlos@the-hubb.co.uk · September 10, 2013, 08:49:07 AM

Quote from: PhilippeV8 on September 10, 2013, 07:46:42 AM
What if you change your "solid glass" or "glass" material for "translucent plastic ?

I have "Translucent" not "Translucent Plastic" but I did just try it and it doesn't seem to do much.

carlos@the-hubb.co.uk · September 10, 2013, 09:47:55 AM

Hi all, I got it now!! it was to do with the power of the light, I had to reduced the watts to 0.5 or 1watt to eliminate the spray effect.
Thank you for all your input; your suggestions were very good and can be applicable to other projects.
Cheers
Carlos

PhilippeV8 · September 10, 2013, 11:49:52 AM

Yeah, I did notice that too ... was one of the first things I did in your scene .. forgot to mention it tho. Also I made the light less blue toned.

Its weird, but I find it very often that if you set a standard 35W strength, you end up with a very powerfull light indeed. I often have .2 or .5 Watt values in there.