Vray lightning calibration question

[remKa]

Hello !

 

For a correct interior lightning, is doing a test with 3 different override "colors" ; 254 254 254 white, 128 128 128 grey, 1 1 1 black ; a good idea ?

 

I mean, in the order to have no burning areas in the white test, nice lightning diffusion in the grey one (I guess), and no pure black shadow areas in the black test.

 

I got very flat renders when I put "real" materials in the scene, even if I'm satisfied with my overridden renders....did I miss something ?

 

Thanx in advance

[LuckyST]

try some other colour mapping method.

and try checking out the "gamma 2.2" threads around the forum.

it would help you achieve much better renderings with minimum tweaking of your max.

 

here's a nice tutorial on gamma 2.2

 

http://www.aversis.be/tutorials/vray/essential_gamma_01.htm

[remKa]

I already set my gamma to 2.2 in max and vray, but my gamma's screen (laptop) is set to 1...when I push it to 2,2, everithing become completly washed out

[DavidR]

I used to light my scenes in grey, but it looks so different with textures that I gave up. I don't usually set up lighting until everything else is set. Even switching, eg., a lvg rm sofa colour from light to dark will have a huge influence on the amount of light bouncing, so I think the grey override for lighting isn't so useful.

[remKa]

So I guess I should caliber my lightning with a 190 190 190 grey, that will be close to the mood I want to obtain.

 

Any pro around ?

[Tommy L]

your laptop will probably not be gamma 1. It will be 2.2, or, if its a mac, it may be 1.8

The washed out look you mentioned is because you are used to compensating for working in an incorrect gamma workspace.

Read a couple of gamma tutorials (LWF) and you'll get it. When you are learning a different workflow (LWF for instance) it is important to start in a fresh scene. Do not try to convert an old project, it is more complex than starting fresh.

[remKa]

yep I'm on macbook pro, i'll try to fix that. I'll follow your tips, thx

[LuckyST]

here's a couple of tips.

 

when importing textures in max, import them with gamma overide set to 2.2

turn on vray virtual frame buffer and render there to correct the final rendering

in colour correction in vray settings, set gamma to 2.2

 

when saving file, save it, but with default gamma.

 

 

that's about it.

 

since you are on mac, in stead of 2.2 type 1.8.

[DavidR]

here's a couple of tips.

 

when importing textures in max, import them with gamma overide set to 2.2

turn on vray virtual frame buffer and render there to correct the final rendering

in colour correction in vray settings, set gamma to 2.2

 

when saving file, save it, but with default gamma.

 

 

that's about it..

There's more to it than that:

-in colour mapping, check 'don't affect colours".

-your solid colours can be made 2.2 by putting Vray colour map in diffuse slot, then pasting colour in swatch place (switch to 'specify', paste the colour, then switch from specify to 'max' and you'll have the corrected colour, in case you need RGB values)

-in Max preferences, set output gamma to 2.2 for jpg, tif, etc, but leave it at 1 if you save as exr or hdr because they're already gamma-corrected. The painful part of LWF is converting all the solid colours, but if you use mostly maps, it'll be fine. Colours look as you'd expect -it's way better, but you really need to do a few projects to get it to where the result lives up to the hype. Don't give up!!

[LuckyST]

what's the "don't affect colours" for?

it seems like I need to use 10 times greater exposure when applying this for the same sceene?

[remKa]

You are right Lucky, I'm going to set up my gamma to 1.8 ! I didn't know that they caliber their screen like that, thanks

 

 

Hello DavidR,

 

I tought activating "don't affect colors" was just here to have lower noise, in darker areas, in sRGB mode ?

 

I dare ask an other question : how do you do to find the correct balance between lightning "power" and vraycam tweaking , like decrease the f-number?

 

I mean , when do I know if I have to set "Multiplier 15" instead of "Multiplier 4" in my vrayLight or If I have to set "4" instead of "8" in the f-number ?

[LuckyST]

here's a nice tutorial on the exposure.

basically you just keep everything at the default values (except if you are aiming for some photographic effect) and tweak the exposure (lower values are brighter, higher values are darker).

you can also additionally tweak exposure in vray virtual frame buffer.

 

[remKa]

That was very helpful thx , I'm gonna training myself on the subject, I will post a WIP tomorrow

[remKa]

Here is my clay render

 

[remKa]

http://img384.imageshack.us/i/texturised.png/

[remKa]

Here is an other work, what do you think ?

 

http://img394.imageshack.us/i/urbanseatclay.png/

 

http://img73.yfrog.com/img73/803/urbanseattext.png

 

 

I like pretty much my clay render but I don't like the texturised one so much :/

[LuckyST]

the textured one is good. I advise you turn down the reflectivity of the floor material; and the sceen would look much better.

same goes for the red material; a little bit to reflective.

 

Also, try a different crop... try a "wide screen" crop, and should be a lot better.

the room is too small for such a wide angle.

[sdds]

dont effect colours is to let vray render in 2.2 gamma but not bake it into the final image. The point of this is to reduce noise in shadow regions.