I'm doing a music video which absolutely needs some slow motion footage, but I only got a 5D mk II. I messed about with AE and this is a simple way to do slow motion without any 3rd party plugins (Twixtor, BorisFx) and it still looks pretty nice. This doesn't replace a good high speed camera, so don't expect to get that kind of quality.
First up: Before you're shooting, set your shutter speed as high as you can. Bump up the ISO if you need to. This eliminates most motion blur from the footage so the effect looks better.
Then open up AE and make a new comp. Make sure the comp is longer than your clip. Put your footage in to the comp and right click it. Choose Time- Enable time remapping.
Then there should be the time remap effect and a couple of keyframes in the layer.
The first keyframe tells where the start of the clip is and the last one tells where the end of the clip is. You can make the clip faster by bringing the last keyframe closer or slow it down by moving it farther. There's also the possibility to ramp the speed around by making more keyframes, but that's another story.
So move the keyframe towards the end of the comp and stretch the end of the footage to the keyframe.
Right click the layer and choose Frame Blending - Pixel motion.
And here's my result: http://www.youtube.com/watch?v=WjOSh0huLZ8
Of course the action is pretty slow in my example (as it will be in my music video that's why I made this test) so your mileage may vary depending on what you're doing.
