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View Full Version : Rendering to exact RGB vaules!



aldoktor
11-23-2012, 11:48 AM
I am doing an architectural rendering of a house and given exact rgb values of the materials to match. Of course after the lights and shadows hit them they change color. Is there a way to keep the exact RBG vaules inputted into the surface editor so they are the same when they are rendered? Is this what sRGB rendering is for?

Thank-you for your comments.

doc

Chrusion
11-23-2012, 04:32 PM
Well, of course rendering is going to alter VALUE (lightness/darkness) of hues, but not the HUE itself (vector direction on a color wheel). There's no way around that except by making surfaces 100% luminous and 0% diffuse, which just looks silly as there is no longer any highlighting and shadowing, etc.

aldoktor
11-23-2012, 04:48 PM
Ah yes, I guess I am looking for some sort of a plugin that would re-adjust the values according to the lights, but thats probably asking a bit much, currently we are rendering alphas and readjusting in PS but I am trying to simplify the process. Thank-you for the comment.

zardoz
11-23-2012, 05:53 PM
aldoktor, that's my way to do it and I think it's the best way. Trying to get the exact colour from the render may be really hard...so just do your light, render your scene, render masks for what you need and adjust the colours in post. I've been doing this for years and there's no other way.

jeric_synergy
11-23-2012, 06:02 PM
I suggest you get a paint 'chip', take it to the client, and rotate it around in front of them.


This would be a great business if it weren't for the clients.....

RebelHill
11-24-2012, 05:19 AM
Well, of course rendering is going to alter VALUE (lightness/darkness) of hues, but not the HUE itself (vector direction on a color wheel). There's no way around that except by making surfaces 100% luminous and 0% diffuse, which just looks silly as there is no longer any highlighting and shadowing, etc.

Quite right... if you wat the EXACT rbg val entered for each surface at every pixel in the render... then 100% pure white lighting/or self illumination, no lighting, shading, reflection etc... is the ONLY way you can achieve it. Even if you found some magic plugin, or photoshop workflow that tweaked shadows, etc to "bring them back"... the resultant image would be identical to a 100% rgb render... it would HAVE to be if the same rgb val is to be at each pixel for a give surface... its the only possibility. If thats what the client is asking for, then just send em a couple such renders, and when they notice how ridiculous they look... then you'll be able to move forward.

Sensei
11-24-2012, 05:36 AM
You should show us rendered image and what we should expect RGB.

Maybe you're simply not following rule that all light intensity = 100%?

f.e. if light 1 has 100%, light 2 has 100%, ambient intensity has 5%, in some situation you might be even getting pixels 2.05x higher value than entered RGB.. (or even worse if light has falloff exponential inverse distance^2 especially and is very close to surface, or very high distance)
Or even more if you're also using specularity, reflections, refractions and GI.

f.e. you have surface with color 10,10,10 diffuse 100%. It's almost black, right?
But light has 100000% - and rendered image will show whitest white color of surface..
Everything adds up.

kopperdrake
11-24-2012, 03:36 PM
"Your image of the brick you have specified is in the sunlight, the one in this render is the exact same image, it's just in the shade." Gotta love clients...