glossy refraction causes bright blotches

[Gijs]

I am experiencing very bright splotches during light cache calculation (and in the actual rendering) when I use transparent material with glossy transparency (for example glossyness=0.9). Anyone else noticed this?
The effect is more clearly visible when affect shadows are on.

When setting glossyness to 1.0 there is no problem.

I don't have time right now to upload an image, will do this later.

[DanielBrew]

I think I'm having the same problem.

If I add a map to the Refractive Glossiness slot then the render changes from the top image to the one below.


No glossy refraction


With glossy refraction

Does anyone have solution or a workaround for this?

Dan

[instinct]

What map are you adding ?

Thorsten

[Da_elf]

where is the glossy refraction being added to and whats up with the blur on the RPC people

[DanielBrew]

where is the glossy refraction being added to

I'm trying to add a band of 'glossy' refraction to the glass partitions. If you look at the glass behind the 3 people on the bad visual there is a continuous red stripe from the woman's shoulder to the right hand edge of the image. That is where I've applied the map to the glass. You know the sort of thing, usually seen in public buildings to stop people trying to walk through glass doors (without openning them first ) etc.

whats up with the blur on the RPC people

There's nothing up with them, they're axyz-design people that I've motion blurred.

Dan

[DanielBrew]

What map are you adding ?

Here's the map I'm trying to use:


Its quite simple, the background is RGB 255,255,255 (white) to represent a 'glossiness' value of 1 and the 5 bands are RGB 195,195,195 which is supposed to represent a 'glossiness' value of roughly 0.75.

I'm sure I've done this sort of thing before successfully.

Thanks for your interest instinct and Da elf.

Dan

[percydaman]

are you using interpolated glossies?

[DanielBrew]

are you using interpolated glossies?

No I'm not but I will try re-rendering the scene now using them....

Thanks.

[RErender]

You might try to "apply cropping" on the bitmap, also make sure all the faces have UVW's if it is a box with planar mapping it could cause an issue.

[DanielBrew]

Right, interpolated glossies have exactly the same effect as non interpolated, it was worth trying though.

RErenderer, I have applied cropping to the bitmap, in fact I used your excellent apply cropping script to make sure it wasn't another rogue bitmap in the scene.

I will try different UVW mapping methods on the glass but I'll have to try it tomorrow because I'm going to get kicked out of here - its 6pm and they don't like me working late .

Thanks again for all the help, if I do find a solution I'll post it on here in case anyone else has a similar problem.

Dan

[Gijs]

Since this thread is heading a completely different way, I will post my images in a new thread