What is wrong with my opac's ?

[zeilveen]

Im working on a old project that needs changing before monday. I used to use alot of opac bitmaps to do green vegetation. Rendering the scene gives black opac object, like if the opac bitmap is not working right.

The problem must have occured after instaling max9 with the new vray 1.5 rc 3 in place. Same problem occurs with rpc's. Im on a deadline and need to know if I can fix this?



Please advice,

Thanks
Ronald

[zeilveen]

another picture here, look how the error is also depanding on the view angle of the camera, some bitmaps are done right?




Ronald

[SvantePanter]

For some areas it looks like the opacity has a different mapping than the diffuse. How does your material setup looks like? Are you using png with inbuilt alphas, or one image for diffuse and one for opacity?

If you can´t solve it, maybe you just can add vegetation in Photoshop afterwards?

[percydaman]

the grass thats good and the grass thats bad... your sure both have the exact same material?

[zeilveen]

Its the exact same material !!

I've been using some bitmaps for two years or so, so why is this happening now? So strange. Also the home made rpc's (single image rpc's) have the exact same problem.

Under some angle the opac bitmap just flashes into black. I've emailed archvision about this aswell. I know vray isnt good with opacs but this is silly. I've bought 3D trees and bushes so the problem will not occur in new models, but I have to adjest my existing projects!

[studioDIM]

It may be entirely unrelated (and this be a "silly" bug in rc3), but try for fun to lower transparency cutoff by 10 times (add another 0) and see if it fixes it...

Lele

[zeilveen]

WOW

thanks for the tip, it didnt work, but had me thinking and I tried changing the Secundairy rays bias and changed that from 0,0 into 0,01 and it seems to be gone !!! Im just testing some more but it looks goooooood !!