The foundation of a good model is foundation?

yesterday I picked up a package of Stormboyz, Devlan Mud wash, Gretchin Green Foundation paint and Ork Hide Shade foundation paint.

HERE IS MY QUESTION.

The paint is nice, its works out really well.. but why is it called foundation paint? whats the difference between it.. and regular paint?
I have noticed I get a nice mix with Ork Hide Shade and Catachan green on Ork skin.. but I could've gotten the same effect with regular paints, whats so special about them?

Foundation paint is super saturated with pigment. It is meant to get good even coverage using only a coat or two of paint even over black undercoat. I quite like the paints. Vs. regular GW paint you should try painting red or yellow over black. You'll be there a while! And especially if you're not into thinning your paints much you'd wind up wioth a lot of clogged details by the time you had a decent coat of paint. Foundation paint should get the same thing done in a much quicker fashion!

I still super reccomend diluting the paints with at least a little water on a pallete of some sort. Even if you had to do 2-3 coats instead of 1-2 the smooth even finish will be worth it. Especially on a character model!

I normally thin my paints down just a bit when it comes to something like white or a light color... cause yeah then you don't have to slop on two heavy coats and you don't block up a bunch of detail. but thanks for that, I was wondering why they were such a big thing now for GW and was curious if I was just wasting my money.

Also the colours are a little different than the regular range of GW paint. Tallarn Flesh is my absolute favorite straight outta the bottle flesh tone. I use it as a base on all my human skin. Love it! Orkhide Shade is also becoming my favorite way to add the first shading to red. I don't use the others all that often, but on occasion I think they are all pretty damn useful.

Ork Hide Shade for Red? that's something I've never thought, considering how dark a green color it is.

Foundation paints are great for shadows, as the value is a lot more diffuse, the color often has a lot of brown or Grey in it.

A rule of thumb for painting: Shadows should always be a lower value than highlights. Bright colors have a lot of yellow or white, it makes them pop. While shadows are darker, you don't want the shadow value to be as bright and vibrant as the highlights. An easy way to do this is to add a complimentary color to the shadow.

ex: If your main color is red, adding green (the complimentary, or reverse of red) will make its value lower, and more realistic. If your main color is yellow, add blue, if orange, add purple, etc. When you add comp. colors together, it browns out the color. You don't need to add much, but you will see the differences. If your shadows and highlights have the same brightness of color (not of tone; the addition of black as a shade) it looks all wrong.

Art theory 101!