Black objects

[geoff]

Hello,

I've been working on this stair for work, that we built years ago but can't get any photos.



Top right, the glazing bars are black.
Replaced the object, which made no difference.

Vray 1.46.15 and viz 2005
Irr + Lc

Have tried rendering at 3000ish pixels high with high render settings
tried photon map for secondary.
Don't think it's a lighting problem!
Any ideas?

Geoff

[natty]

Hey Geoff ..

are the Bars behind the glass ? .. if so try increasing your global depth.

[vlado]

Maybe their normals are flipped?

Best regards,
Vlado

[geoff]

Bars are in front of the glass.

[geoff]

All of the glazing bars are instances, so the normals should all be one way or the other?
I'm rendering a big one again so I'll post a blow up tomorrow

Geoff

[RErender]

could it be the reflection cutoff?

or maybe the glass is coplanar with that edge?

[Dynedain]

If they're instances and you mirrored them, you can get inverted normals. Looking at the image it seems like it could also be coplanar faces

[natty]

Hey Vlado ... like your Avatar ..... a little hint there hey ??

[meanadam]

My money is on Dynedain... flipped normals.

If you are relying on 2-sided materials - make sure "reflect on backside" is checked.

[natty]

There was a nasty little bug with Mirrored Instance's where it turned objects Black ... but that was rectified..

[TishoChaos]

Try to play a bit with the SRB ... maybe it solves it

[geoff]

Here's a blow up of that area



THink I found the problem. 2 sets of glazing bars. co-planar faces

DOH!

Odd that it's only done it that area when the whole lot of verticals were duplicated

Can't seem to a region or crop render all of a sudden. Why is that?

Tishchaos what is SRB?
.......
Just rendered left to right reversed. Co-planer faces. So who won the bet?

Thanks for all your quick and insightful replies

Geoff

[TishoChaos]

Geoff, SRB is Secondary Raytrace Bias and is located in the Global Switches rollout - if you increase it to 0.001 it can solve the problems with co-planar faces. But the best solution of course is to just delete them.

[geoff]

It's not black anymore......it's grey!



The horizontal bars are the same material and are OK.

I'll keep looking into it......

[TishoChaos]

Did you try SRB? What happens if you hide everything except the problematic objects? You can send me an email with a stripped-down scene if you like.