Hi,
I’ve read this article from CGCookie to use grey card + false color to obtain proper exposure.
Match the middle grey from the Middle Grey Card with the grey on the False Color look in the Filmic color management settings.
My problem is the grey card doesn’t go to “grey” It just ranges from red to blue no matter how I adjust the exposure.
Is there a way around this?
P.S. There is a thread about this but the answer is not conclusive “over-constrained slab of gret”
There isn’t technical details about false color in Blender documentation, yet by testing I figured that dark blues are black values (RGB 0,0,0), magenta and black are underexposed, orange is white (RGB 1,1,1), and red means that it’s ‘burning’, overexposed. Grey 0.18, is the optimal value but in almost all scene’s it’s very difficult to get a lot of it, unless you’re using filmic which will result in a lower constrast scene.
By keeping your whole scene between blue and yellow will get a nice render with a well distributed histogram. If you’re problem is with increasing or decreasing light strenght values, use a math node set to multiply.
False color in Blender isn’t the same as photography monitors:
It’s simply because the light is falling off rapidly, so only a sliver is in the middle grey range.
Thanks for the response and for the illustration images. Helps a lot.
So I guess long story short, blender change and its not possible to have an exact “grey” in the false color and just instead rely on the color being the range of yellow and green to have an optimimum dynamic range.
Theoretically, it’s possible (no lamps, no HDRI, but just one color environment light, etc). But practically not (You have a more interesting 3D scene than that). Or in short, as Troy said: you will see only a small stripe of grey. (Because the fall of is very sharp. It was not that sharp before, but due to a request it is now).
Remember too that the False Colour isn’t changing how the light behaves; it’s just the False Colour evaluation is a little more precise.
Don’t forget that in all of this that in the end, it’s about making an incredible looking image. Don’t get too hung up on technical nerd crap! Instead, focus on making an incredible image that communicates what you seek to voice!
If you don’t mind, I will quote this some more times. It’s something we easily forget. With all his knobs and sliders, Blender makes us easily work the other way around; Owh, what does this button do, yes that’s nice. Versus: Defining first what we seek to voice. What do we have in mind. What is our goal, objective? And then use Blender to visualize our idea.
