Clouds really aren't that hard to do, I think. It's mostly brushes the successs depends on. That said, take care of the general cloudscape when painting, because cloudy skies usually feature a lot more clouds than I often see depicted; also, don't group cloud types together that wouldn't do so in nature (humans have this strange ability to tell when something is right, even when they never conciously looked at it).
Smoke and fumes are similar, but not equal, to clouds, as are stellar nebulae. Remember that clouds are only evaporated water, and thus are very light - fumes are pushed out of chimneys and have different shapes, and nebulae in space don't encounter any atmosphere to form some structures that are normal to clouds on planets.
Hm, apparently there's a lot to say about something as common as clouds
If there are any questions left, feel free to ask. Also see the other Tiny Tips
for more help on other subjects.
"Ranarh's tiny tips" is a collection of iddy-biddy tutorials, each containing small bites of advice anyone can chew, aimed at beginner's level artists. They are not software-dependent. If there's a problem you have, something you feel someone should finally explain, or are just curious what I have to say on a particular artistic issue, feel free to tell me.
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