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Matte issue

Posted: Thu May 21, 2015 6:06 pm
by gueoct
I don“t want to use 3d grass but a grass texture instead and need shadows that are cast onto it.
So I use a matte material for the ground that recieves shadows from house and trees.

1. When i keep the environment on (octane daylight), the shadows get far too bright and the shadows look awful.
2. When i turn environment off, the background gets black and results in pitch black shadows.

Image

is there a way to get the shadows right?
In vray i can play with the background colour and the "alpha contribution" to finetune the result.....

Re: Matte issue

Posted: Mon May 25, 2015 9:07 am
by gueoct
Please, can somebody help me!
i have a deadline to meet, and need some advice from someone who knows about that....
of course i could botch in Photoshop, but if there is a faster way, please let me know!
Thanks

Re: Matte issue

Posted: Mon May 25, 2015 2:11 pm
by akira
Hi, it seems like a bug of pre-multiplying alpha to me.
For now i can only adjust the opacity of the matte material and turn off keeping environment to get the shadow density i want.

Re: Matte issue

Posted: Tue May 26, 2015 7:50 am
by gueoct
Oooops!
Honestly, I never thought about changing opacity of matte material.... ;-(

Thank you so much, akira, you made my day !!!!!!