Welcome to CGarchitect.com Untitled Document

Go Back   CGarchitect.com > MAIN FORUMS > General Discussions

Notices

General Discussions For general discussions about rendering, animations, walkthroughs and CGarchitecture

Reply
 
LinkBack Thread Tools Display Modes
Sponsored Links

Old May 9th, 2008   #1 (permalink)
Senior Member
 
Join Date: Dec 2003
Location: back in Serbia
Posts: 163

Name: Dusan Bosnjak


Serbia 


Default Gamma/LWF versus Kelvins...

When using LWF with vray, i encountered a problem with IES files which work with Kelvins.

The gamma settings are affecting all the color sliders, including the one that is kelvin dependent.

I believe that the results i see in my renderings when using kelvin colors and LWF are wrong, but no one seems to notice or understand that.


This is an image where the room is being lit by a single IES (new vrayIES) light with a color of 8000K.

It is blue.





In this image, the gamma of 2.2 has been applied.




As you notice, it's not so blue any more, giving the impression of a warmer light. this is along the lines of D65 or so.


With GI, it looks like this:



But if i manually correct the color so its back to 8000k, it looks correct.






I would like to hear an opinion on this. Most people thing it's not a problem at all, but i fail to understand the concept. If the gamma setting washes out all our textures and colors and we have to bring them back by applying the inverse gamma, why shouldn't we do it with kelvins as well?
pailhead is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old May 10th, 2008   #2 (permalink)
Senior Member
 
Join Date: Dec 2003
Location: back in Serbia
Posts: 163

Name: Dusan Bosnjak


Serbia 


Default Re: Gamma/LWF versus Kelvins...

Anyone?
pailhead is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old May 12th, 2008   #3 (permalink)
Member
 
MasterZap's Avatar
 
Join Date: May 2006
Location: Eskilstuna
Posts: 70

Name: Håkan Andersson


Sweden 


Default Re: Gamma/LWF versus Kelvins...

Quote:
Originally Posted by pailhead View Post
Anyone?
On the contrary - I'd say that the Kelvin values you see when not using Gamma are the wrong ones. 8000K is nowhere near that deep blue. IMHO, The lighter one is the correct one.

(Disclaimer; at least this applies to the mental ray implementation)

/Z
__________________
mentalraytips.blogspot.com - mr Zap Andersson - a completely mental shader guy

Last edited by MasterZap; May 12th, 2008 at 12:04 AM.
MasterZap is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Mental Ray (Max9) versus VRay !! Whatsay? Macho3001 Mental Ray 17 January 9th, 2007 10:44 AM
add versus screen radii Compositing Software 7 January 3rd, 2007 02:04 AM
MAX versus C4D josephus General Discussions 8 May 1st, 2006 05:35 AM
How abour a versus forum reddy Suggest a New Forum 0 July 21st, 2005 04:58 PM
Stacking versus pancaking Cesar R General Discussions 5 December 26th, 2004 04:25 AM


All times are GMT -7. The time now is 06:17 AM.





Powered by vBulletin® Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.2.0
© Copyright 2001 – 2008 CGarchitect Digital Media Corp. All Rights Reserved.