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spurv
06-06-2007, 03:34 PM
Hi, I'll be very simple.
I'm trying to render a plane with a transparency at 100%, my light is casting a raytrace shadow, and what's hapenning is that the object is totaly transparent and that's good, but o th other hand, my shadow is still 70% visible.
I'm using maya 8.5 with the sofware render, mental ray behaves the same, and this is very stange.
I'll put an image to illustrate.

Ohh, this problem happens also when mapping a alpha to the transparency channel.

bwheels02
06-06-2007, 11:47 PM
Try turning the 'shadow attenuation' to zero within the material/shader attributes that's applied to the object casting the shadow. That should work. Hope this helps. :)

spurv
06-07-2007, 12:48 AM
Thanks bwheels02, it works great.
I would never had looked at that attribute, in previous versions of maya this had never happen but in 8.5, i'm constantly running into strange issues, like not being able to frame my material in the hypershade or doing a split poly and maya crashes.

Big thanks man.

Lazar
08-23-2007, 10:15 AM
Try turning the 'shadow attenuation' to zero within the material/shader attributes that's applied to the object casting the shadow. That should work. Hope this helps. :)

yes, this helps. But only in default settings of both render - SW a MR.

When I turn on in MR all -> GI + FG. It isn't OK. Material transparency [lambert] ignore cast shadow and shadow in result is "full".
See attachment...

Thx for help

bwheels02
08-23-2007, 05:56 PM
yes, this helps. But only in default settings of both render - SW a MR.

When I turn on in MR all -> GI + FG. It isn't OK. Material transparency [lambert] ignore cast shadow and shadow in result is "full".
See attachment...

Thx for help

**Ignore previous private message**
It is okay. If you are using GI there is a setting which for some dumb reason is turned off by default, causing all shadow or no shadow (very frustrating, i know). If using transparency/alpha go to the Render Globals > Mental Ray tab > GI turned on > put a Check in the box next to "Direct Illumination Shadow Effects" YAY that should do it!

If not check your Trace depths values in Raytracing, GI and FG. :)

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