Rendering realistic looking water in a painting or illustration is a very difficult task, since the translucency of water is hard to replicate, but can you imagine how impossible it would be to actually draw on water?
Without the use of foam or a similar substance floating on the surface ink or paint or any other medium simply dissolves in the water, but dry erase marker ink actually floats on the surface and retains its shape remarkably well.
This video from The Action Lab shows you how it's done, and watching doodles float is really fun!
That's amazing!
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