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HDRI causing stroke on render.
show user profile  jkcal436
HDRI is causing a stroke / highlight on object when rendered to alpha channel. Have used standard and arch & design materials with no highlight / gloss / specular. The stroke only appears on the brightest parts of the HDRI.
mental ray stroke
hdri mr stroke
read 409 times
4/28/2015 1:46:48 AM (last edit: 4/28/2015 1:48:36 AM)
show user profile  Bolteon
You're referring to this, yes?

-Marko Mandaric

read 391 times
4/28/2015 2:34:20 AM (last edit: 4/28/2015 2:34:20 AM)
show user profile  jkcal436
Yes, after some digging it is called "alpha halo"?

read 388 times
4/28/2015 2:50:52 AM (last edit: 4/28/2015 2:50:52 AM)
show user profile  Bolteon
Ahhhh, I thought you were referring to the different coloring of that one "bar" of the structure.

Yes, that halo effect is what you get when you use an environmental background that isn't black and you don't properly un-multiple an alpha from it's RGB.

Easiest solution, switch to black. Unless you're compositing on white.

Then render on white.

If you're compositing on color? Un-mult.

-Marko Mandaric

read 385 times
4/28/2015 2:55:04 AM (last edit: 4/28/2015 2:55:04 AM)
show user profile  jkcal436
Can you point me to a site or what to research. I am a noob on this. Thanks.
read 383 times
4/28/2015 2:57:21 AM (last edit: 4/28/2015 2:57:21 AM)
show user profile  Bolteon
Essentially it's a baked in clipping of the area around an object based on the background that it's rendered against.

If you're trying to get rid of it; there's several ways... This is one of the more proper ways (but you need After Effects for it), note I've never used this plugin myself:

-Marko Mandaric

read 370 times
4/28/2015 6:36:44 AM (last edit: 4/28/2015 6:36:44 AM)
show user profile  Mr.Burns
Edit: disregard this
read 369 times
4/28/2015 6:44:26 AM (last edit: 4/28/2015 6:45:49 AM)
show user profile  Coxy
If you are using Photoshop the defringe option can help (If you can't go back and do what Bolts suggested).
read 335 times
4/28/2015 6:44:53 PM (last edit: 4/28/2015 6:44:53 PM)
show user profile  chillywilson
if you have to deal with that in after effects just use a choker, matte choker or simple choker.

read 322 times
4/28/2015 7:56:51 PM (last edit: 4/28/2015 7:56:51 PM)
show user profile  Bolteon
Isn't choker like a contracted selection?

That's not exactly properly un-multing.

-Marko Mandaric

read 303 times
4/29/2015 2:44:16 AM (last edit: 4/29/2015 2:44:16 AM)
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