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alitavanaie
05-25-2009, 08:51 AM
Hi every one
I am using 3dsmax for light engineering .
but the problem is that 3dsmax rendering system is based on camera and camera systems , and i want to show how can lights illuminate scene in Humanís eye view .
i am using vray as rendering engine and then i want to know how to change exposure and color mapping factors to make best results.
there was nothing in 3dsmax/vray help to help me.

mister3d
05-25-2009, 09:24 AM
It's impossible I think to make, because when you look outside of the window your sight is accustomed, but when you look at photo, it won't. Or it must be like an hdr photo, where all exposures are like you look directly at them.

alitavanaie
05-25-2009, 01:14 PM
but some of 3dsmax max exposures has an ability to calculate light of the scene and then change its settings.
for example when we have less light in the scene , colors will be more gray.
by the way i donw want realy true sight T i want best one that is possible. i want that when i place 300cd projector in the scene, it looks like what it would be in real world , to show how much light is needed there

phix314
05-25-2009, 08:41 PM
I agree with mr3d, HDR would be the best way to go.

mister3d
05-26-2009, 03:59 AM
First of all describe the diferences you see between the human site and camera.

FrancoisvdW
05-26-2009, 11:35 AM
Heya! The human eye adapts the local and global contrast of an image to even things out. So the best answer I can give you is to Render in 32/16bits per channel (HDR) and convert it back into a 8-bit image using your favourite photo editing program's "local adaptation" function.

Check my related discussion on this topic:
http://forums.cgsociety.org/showthread.php?f=176&t=745440&highlight=adjusting+human+eye

There's lots of useful links there...

noouch
05-27-2009, 09:54 AM
Here's a neat list of tone mapping algorithms, some are specially designed to imitate the response of the human eye:

http://osp.wikidot.com/parameters-for-photographers

V-Ray's HSV exponential and Reinhard color mapping modes also do a pretty good job.

If you decide to go with linear color mapping, make sure your gamma is set to 2.2.

frizDog
05-27-2009, 11:56 PM
Unless you are looking these images on some amazing HDR monitor, or are outputting to 35mm film, the display device you use will not be able to display the color depth or gammut your eye can see anyways.
go linear float.

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