Heightmap Help?

[The_Black_Cat]

How do people create realistic, natural landscapes with heightmaps? Whenever I try to make a natural map, my heightmap always ends up too flat, or has bits that stick up too much, or it is too square, or you can see where smudge marks and such are. Does anyone have tips on how to make a natural and (for lack of a better word) "flowing" heightmap?

[Hooli]

-Detail to make sure the land isn't unnaturally flat. Try to match up the amount of detail to the type of map it is. For example if you're making a forest map you want to have lots of small little hills/bumps and creeks and whatnot. If you're making an African-themed map I'd suggest flatter land, wider, shorter hills, and less rivers/lakes.

-Lots and lots of blurring. Make sure everything blends in together and transitions smoothly.

[Kerriki]

Another suggestion is making the heightmap while using several layers in your art program and then flattening them when you're ready to use it

[Spottedbears]

Genesis199 has a three part tutorial on advanced height maps. They use photoshop for the tutorial but I got along just fine with SAI, then converting it to grayscale with GIMP once it was finished.

I also suggest never making any large section completely flat. Of course, little sections for camps, houses, etc. are fine, though land is never completely flattened out in a natural area.
The map's mask can help a lot too; if you blend the terrains and have different terrains with lowered opacity blurred over others (i.e. very faint green drawn on top of some red)

[The_Black_Cat]

Thank you everyone for all the tips! I'll definitely keep those in mind, they were very helpful!

(And I officially love you Tailgate, for linking the tutorial. That was exactly what I needed. The kind of maps Genesis199 makes were what I had in mind in the first place.)