Adobe Photoshop. It's a pain, but do it the right way. You have to take one entire image, usually the first or last. Then you go to the other pictures and cut out the skier with the best precision you can. You need a steady hand on the mouse. Then import that to the original pic, and turn the opacity down. When you get it aligned with everything else, (which sometimes takes forever because one pic might have been at a slightly different angle) and set in the right spot, turn the opacity back to show the skier and not what's behind them. Then do that for each pic you want. It also really helps to use a tripod and dont move the camera when you first star doing them, because then you dont have to worry about different angles. And please dont do it the lazy way, where you can tell where each pic was taken. Make it look like there was one frame used. Good luck bro. I'd upload some of mine, but they're to big to fit on NS and they suck when they're compressed.
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