High Dynmic Range model edge

[Travis Schmiesing]

I have had this problem since I started using HDRI's for GI.

I have had this problem since I started saving files in a High Dynamic Range format. The edge of the model does not blend/AA smoothly. I get a funny line. If I save the file in an 8 bit format, there is not a problem.

If I want to do post process depth blur, etc... this becomes a problem. The only way I can think of around it would be to render wioth a sky dome, so there is no 'edge' to the model.

...but I was under the impression that I shouldn't have to do this. I should be able to use a HDRI image for my GI, and also assign it as the enviroment map, and have a seemless image.

I posted a similar question about a problem with AA around Vray Light materials a couple of days ago. Someone responded by saying that the High Dynamic Range format was causing this because of the light intensity at the efge of the material. It made sense, but I felt it was crap as far as the file format goes. A weekness that there has to be some way around, but that I don't know as of yet.

So, any ideas.....

I am having the same problem with HDR, EXR, RPF formats.

[Oleg Bogattke]

Hello Travis,

I was the one who answered in your thread, but I haven't said
it was because of the fileformat but because you don't clamp
colors in linear workflow mode. A quick question for you. Did you
try to use HSV instead linear colormapping? I would like to know
if this happens with HSV too. ;o)

nb: I've the feeling that vlado's answer was something like
you have to use HSV ... I'm to lazy to search for the thread
at the Chaosgroup forum right now.

edit: I haven't found the thread yet, but maybe this thread
is helping you also, specialy the post of joconnell ... klick.



take care
Oleg

[Travis Schmiesing]

hmmm... i am using HSV exponential on this scene, and i have it clamped. iam using Adaptive QMC with Mitchell-Netraveli for AA.

as you can see, it looks fine in 3dsmax. it is when i open it in Photoshop or Aftereefects that i am experiencing my problem.

[Travis Schmiesing]

i found my problem. when saving as either EXR or RPF i had 'pre-multiply' alpha turned off. turning this on made the edge transition smoothly.

i also lied. i was not having this problem with HDR format. i don't know why i thought i was.

[Oleg Bogattke]

Ooooops, ... well Travis now we are two monkeys. ;o)
The good thing is, if someone is having a problem
like this ... I can add a new question to my post.




take care
Oleg