Opacity

aflack · August 3rd, 2004

Can anyone tell me why when I apply a tree material to a flat plane, and apply an opacity map to the opacity channel, when I then render using Mental Ray there is a brighter area around the tree where there should be nothing.

See attached image.

Thanks

STRAT · August 3rd, 2004

switch off all specular/shiney properties of the material

jysngltndz · August 3rd, 2004

yup glossiness and speculars, try removing it...what shadow type are you using? as i know raytraced shadow works well with opacity. just try it with mr.

aflack · August 3rd, 2004

I guess I must be doing something wrong, I have taken all the specular and gloo off the material. Also I am using Ray trace shadows.

Have a look at my material settings below.

Thanks for yoru patience.

wda · August 3rd, 2004

aflack,

Two things to consider

1. is your mask absolute 000 & 255 (black white), adjust that map in the Materials>output>colormap to see if that eliminates the problem or check in PS

2. Environment effects such as fog always brighten the 'opaque' or masked part of an object, turn it off if using

rgrds
WDA

e-p.s. thats some funny looking 'frosted glass'

LOL

jucaro · August 3rd, 2004

Check enable PROCESS BACKGROUND AND ENVIRONMENT MAPS in your exposure control found in the environment tab of your environment and effects dialogue.

kicks · August 4th, 2004

<if you are using sphere containing your scene, just apply 100% transparent material to it (standard mat'l. opacity=0). hope this helps

aflack · August 25th, 2004

Thanks for all your help, I ended up placing the tress in Photoshop but in my new image I want the trees to reflect in the glass.

I tried what Jucaro suggested and it does get rid of the glow round the trees but it blows out the background image as well.

There must be a way around this if you want to use an background image thats also my environment map?

Please see the attached images for what I mean!

noi-pi · August 25th, 2004

Thats exactly what happen to my opacity maps if i didnt check process env maps. It works but what happen was just like that! Overblown env background. From then on I shy away with Exposure Control. Besides I don't want to add another settings aside from Render Dialog box.

aflack · August 25th, 2004

So is there no way you can get around this then?

August 3rd, 2004	#2 (permalink)
STRAT Super Moderator Join Date: Dec 2001 Location: Cardiff, Wales, UK. Age: 36 Posts: 6,486 Name: Stephen Leworthy	Re: Opacity switch off all specular/shiney properties of the material

August 3rd, 2004	#3 (permalink)
jysngltndz Senior Member Join Date: Mar 2004 Location: cebu city Posts: 206 Name: jayson giltendez	Re: Opacity yup glossiness and speculars, try removing it...what shadow type are you using? as i know raytraced shadow works well with opacity. just try it with mr. Last edited by jysngltndz; August 3rd, 2004 at 07:28 AM.

August 3rd, 2004	#5 (permalink)
wda Veteran Member Join Date: Nov 2002 Location: Dallas TX USA Age: 44 Posts: 1,021 Name: William Alexander	Re: Opacity aflack, Two things to consider 1. is your mask absolute 000 & 255 (black white), adjust that map in the Materials>output>colormap to see if that eliminates the problem or check in PS 2. Environment effects such as fog always brighten the 'opaque' or masked part of an object, turn it off if using rgrds WDA e-p.s. thats some funny looking 'frosted glass' LOL __________________ From the calm seas.... Into the CG Fire...... Into the Heart of Texas Last edited by wda; August 3rd, 2004 at 10:45 AM.

August 3rd, 2004	#6 (permalink)
jucaro Moderator Join Date: Jul 2002 Location: Singapore Age: 32 Posts: 612 Name: Juan Carlos Rosalejos	Re: Opacity Check enable PROCESS BACKGROUND AND ENVIRONMENT MAPS in your exposure control found in the environment tab of your environment and effects dialogue. __________________ MD8 Design Solutions X3MFX Interactive Design Agency DE MAX Design PTE LTD

August 25th, 2004	#9 (permalink)
noi-pi Senior Member Join Date: Feb 2004 Location: Morocco Posts: 113 Name: Herminio Jalocon Jr.	Re: Opacity Thats exactly what happen to my opacity maps if i didnt check process env maps. It works but what happen was just like that! Overblown env background. From then on I shy away with Exposure Control. Besides I don't want to add another settings aside from Render Dialog box. __________________ We manufacture modern antique furniture.

August 25th, 2004	#10 (permalink)
aflack Senior Member Join Date: Jan 2004 Location: London Posts: 281 Name: Adam Flack	Re: Opacity So is there no way you can get around this then?

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