Vray Fresnel reflection weirdness

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

THREAD CLOSED
 
Thread Tools Search this Thread Display Modes
  03 March 2013
Vray Fresnel reflection weirdness

Lately I've been trying to get some subtle reflection around the edge of the object. But no matter how I try, once I lower the IOR or lower the reflection amount, there is always some sharp cut off happening. The effect is not very noticeable in linear space... but as soon as I turn on sRGB, well...

Here's a simple sphere. Vray Mtl, black diffuse, white reflection, pure white reflection over-ride. Fresnel IOR 1.1. Left is linear without color correction, right is with sRGB applied.



Here's the same scene, replacing the white reflection over-ride with an HDR



Any advise how I to deal with this? I tried connecting ramps with sampler info myself but the result is still the same.

Thanks.
Attached Images
File Type: jpg srgb1.jpg (10.3 KB, 121 views)
File Type: jpg srgb2.jpg (15.8 KB, 115 views)
 
  03 March 2013
You need to turn the reflection cut off threshold down to 0.01 or something like that -its in the vray mtl settings. I end up doing this on most of my very glossy materials
 
  03 March 2013
Ahh Thanks terminvox! The label only says Cutoff threshold, wouldn't have thought it's for reflection.

 
  03 March 2013
Originally Posted by terminvox: You need to turn the reflection cut off threshold down to 0.01 or something like that -its in the vray mtl settings. I end up doing this on most of my very glossy materials


0.01 is the default.
 
  03 March 2013
Originally Posted by cgbeige: 0.01 is the default.

Apparently. I had to lower it to 0.001, or in extreme case, 0
 
  03 March 2013
Oops. Beige is right -but I guess it was obvious what I meant.
You probably know about this but some really nice tips for vray materials here..

http://bertrand-benoit.com/blog/201.../materialism-1/
 
  03 March 2013
thanks - that looks great.
 
  03 March 2013
Thread automatically closed

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.
__________________
CGTalk Policy/Legalities
Note that as CGTalk Members, you agree to the terms and conditions of using this website.
 
Thread Closed share thread



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 08:16 AM.


Powered by vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.