Keeping Mist off the Environment

v2.72 Love the Mist pass but still use GIMP to get the Mist off the Environment/sky and clouds and such. What is the proper way to do this internally?

You can use the compositor to do the same you do in Gimp. Add fog with a offset/lift node or mix a color with the mist pass as the factor. Is that what you’re looking for?

You could also mask the mist pass by the inverted normalized Z-Depth.

Offset/Lift is unheard of to me if that gives you any idea. My Composite Node knowledge is sad. Using a color with the mist as factor is a neat trick I’m able to relate to with GIMP. I believe my big issue would be learning how to mask out the environment. I’ve never gotten the hang of that.

Can you show what you want to do? With a blend and a rough example in gimp maybe?

Here is the node setup I mentioned. As you can see the mist is removed from the sky, but the entire look is unnatural.

Attachments

27_mist_not_on_sky.blend (267 KB)


Helpful screenshot, Atom. You’re right, that sure is an odd result. I’ve attached a perfect example that I happened to make just a week ago.

I had a good sky, my Mist pass and an improved ground that the render with the sky didn’t have. I used GIMP to cherry pick the sky, use the mist on the good ground and then a Magic Wand to cut the mist from the sky leaving a jagged edge at the pixel level where the sky meets the mountains.

I’m glad I made the clouds, I love the Mist and the ground is still WIP, but the effort of putting it all together must be easier than what I did! :slight_smile:

Since this picture is WIP, the issue is still very alive for me. Landscapes are my white elephant at the moment.


Render with an alpha channel, then subtract the alpha channel from the mist. (or invert the alpha and multiply the two).

I think it’s very safe to say that all of that “cool, ‘natural-looking’ stuff” that you like to admire … comes from a firm understanding of and use of the compositor.

Maybe it helps to be a computer-programmer, because that is very much “what you’re doing.” You’re constructing, in effect, a data-flow program, graphically. Breaking a data-stream down into its component parts and combining it to produce a “natural-looking” (or my favorite oxymoron, “photo-realistic”) result. It looks like “the Christmas jigsaw-puzzle” when you’re doing it … all spread out on the table, covered-up so that the cat doesn’t knock it asunder [again …] … and then, it all just fits together to make a picture.

A photography teacher once stressed, “Look at the light.” Not the subject, not the scene … literally, the light. And, understand how photographic film will interpret that light. With compositing, that notion is still true. Go look at the real-world setting or scene that you’re trying to imitate, and regard it critically. Analytically. It will introduce you to a different way of staring at things.