background visible through transparenies

[ABK]

Hi everyone,

 

I have a recurring problem with transparencies with mental ray for 3DS max and have had the same problems with mental ray for XSI.

 

I frequently use a background image with camera visibility off for reflections (or I use an environment). However, with transparencies the background image is rendered into the object instead of the background colour.

 

The image attached shows an example of this.

 

Does anyone know a way of stopping this happening???

 

I have had the same problems in XSI when I turn the primary rays of a background object off.

 

 

Cheers,

Antony

[mattclinch]

its a known issue. i believe there is a work around using the 'Raytype Switcher' production shader. this sits in your A+D material diffuse slot and allows you to define the colour of bounced, reflected, refracted etc rays. i believe jeff patton has a good blog entry on the unlocking and use of this shader -

 

http://jeffpatton.cgsociety.org/blog/archive/2008/1/

 

let me know if that works - haven't this issue for a while so not tried this work around.