Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: kocabiyik on 2017-02-04, 12:36:28

Title: White Borders On Trees
Post by: kocabiyik on 2017-02-04, 12:36:28

Hi, i have white border problem on trees and i can't solve it.i tried alpha source =none, corona outputmap, but problem isnt solved.(Note : CUPRESSUS tree is not have opacity map , only colour but it have white border too..)

Title: Re: White Borders On Trees
Post by: v.p.vlasenko on 2017-02-04, 13:05:05

Seems like I had similar problem with white borders and global volume mat.

The reason was - refraction used in leafs material due to use of automatic converter for evermotion models/vray materials.
Check leaf material setup. If refraction used - remove it(refraction shouldn't be used for leaf - use translucency), should solve problem.
That's the only idea I have.

Title: Re: White Borders On Trees
Post by: subpixelsk on 2017-02-05, 16:39:54

did you render with black background or some sky backplate?

Title: Re: White Borders On Trees
Post by: Geezer on 2017-02-05, 20:30:07

I think this is happening because of the opacity map.
Even if you are using a diffuse map the diffuse color is still affecting the outer border of you opacity map.

Change the diffuse color to a darker green similar to your texture using for the leaves.

I can only guess but I think it is in connection inside you opacity map settings. (clipping maybe) ?

________

If its not the problem of the leaves it will be the environment.
Try not rendering your sky into you image. (visibility settings in the environment tab)

Title: Re: White Borders On Trees
Post by: David Males on 2017-02-06, 11:46:07

Try filtering on your opacity map, it should help a little bit..
But this happens to me as well, so you can use a little trick with photoshop : Control click your alpha image (which will select white) then go control shift I to inverse selection and then modify selection - expand (1-3px) depending on your resolution ..  then you can use soft brush with black color to get rid of these pixels causing trouble..  It takes some time to get it done nicely but its worth it I guess..

Good luck!

Title: Re: White Borders On Trees
Post by: v.p.vlasenko on 2017-02-06, 13:43:04

Guys, when you say about problems with opacity map you're missing one important thing - "Note : CUPRESSUS tree is not have opacity map , only colour but it have white border too.."

So that's not opacity map and I don't think it's some alpha channel problems. I had exactly same problem when there was refraction in leaf material. Notice that some leafs not only have white border - they are completely white at grazing angle.
I was a bit wrong in my first reply - global volume mat made those borders better visible in that particular scene, but the problem was there all time and it described above.

Title: Re: White Borders On Trees
Post by: maru on 2017-02-14, 16:15:09

Are you using Photoshop to remove background? If so, then this topic was discussed a million times. :)
Here are answers:
https://forum.corona-renderer.com/index.php/topic,4742.msg32510.html#msg32510
https://forum.corona-renderer.com/index.php/topic,8915.msg57776.html#msg57776