hey all, wondering if anyone has any ideas on how to make steam coming off a mug. I'm wondering if I should use cotton balls or polyfill as the steam. Should I shoot on black and then overlay in afterwards in post? I really dont have any idea on how to even animate such a thing. I'm sure I could find some stock footage but I'd much rather do it practical. Any advice would be helpful, thanks!
I know of a few ways to approach animated steam. In fact I used cotton for mist once long ago, but it was well before I found this site and learned how to animate properly, and it looked pretty much like thick wads of cotton being occasionally moved around a bit.
Cotton balls can work, but be careful what kind you get. Some of them can be unrolled and are like little sheets of cotton wool that have been rolled up into balls - these are decent because when you unroll them the fibers are all in alignment and it's easy to pull them apart and work with them, but I've also used cotton balls that are just somehow randomly packed into lumps that can't be pulled apart because the fibers are just running in every direction. I don't know who makes which or how to tell which kind you're getting. But if you buy a roll of surgical cotton then you're assured of getting straight fibers that you can work with. If your corner drugstore doesn't have surgical cotton ask the druggist - they'll gladly special order some and have it in in a few days.
What you want to do with cotton to make it look like steam is pull off just a super-thin wisp of it and tease it apart gently until it's almost non-existent. You can peel off a remarkably thin layer and then keep working at it until it's barely there.
And ideally you would shoot it out of focus. Maybe on a piece of glass that's closer to the camera, or maybe as you said shoot it separately against a black background and composite.
Alternately, there's an old trick that was in use even before movies - in stage magician's tricks for example, called Pepper's Ghost:
Though for stopmotion of something like steam I think it would work best to tilt the glass downward at 45 degrees so it's aimed at a shelf just in front of and below your table. Then you could have black paper or fabric there and animate a wisp of cotton on it with a small light aimed down at it. Fabric might work better than paper because you might be able to get the cotton to sort of stick to it if it has the right kind of surface, which would help hold it in place where you want it.
Another variation of this would be to have a sheet of glass in between the camera and set and smear vaseline on it that you could animate frame by frame.
Oh, also the cotton can be airbrushed or painted with a wash or something to make it look gray.
It's hard to animate smooth movements throughout the whole mass of cotton so it looks like steam. It works best for a quick burst of steam, not so good when it is lazily swirling about.
For a recent film Not my own), I took the easy way out and shot real steam live, then composited it into the scene. You can see a looped clip of it on the front page of the website. It's at the top of the page but takes a minute to load.
But sometimes you want the handmade look, and it doesn't matter that it doesn't look real, then cotton is good.
You could try hanging a thin layer of cotton close to the camera so that it becomes out of focus. Just place it carefully in a way that it looks like it's coming from the mug, and animate it frame by frame, first adding some cotton, and then taking some out. Hang it with a few thin fishing lines.
This is how I saw that cigarette smoke was made for a stop mo film in Slovakia. It was animated by an oldish animator who used to work for Jiří Barta.