I'm fairly new to After Effects and I was wondering what the workflow was for getting a video closeup of something like an iPad or device hitting the floor and the glass screen shattering.
Thanks so much.
Two crucial questions:
When you say "shatter", do you envision glass flying all over the place as it hits, or just the screen cracking?
Does this have to look photorealistic or more cartoon-like?
One way to do it would be to duplicate the video layer and manually roto or mask out just the frames of the screen when and after it impacts, precomp the roto-ed or masked portion of the ipad screen, add the AE Shatter effect and play with the settings until you get something that looks more or less realistic. Or if you have CS6 you could try using the 3D Camera tracker to add a null object onto the ipad screen. Then for added realism you could try getting a photo of a smashed iPad monitor or computer screen, parent it to the null, mask it to fit the ipad screen, add the shatter effect and adjust the effect and mask it as it moves after the impact.
However, if you're going for a really pro photorealistic shattering glass effect you may need to look into 3D software: Andrew Kramer from video co-pilot does a fantastic shattered glass tutorial called Advanced Time Freeze using After Effects and 3Ds max. It's for moving through broken glass that has been frozen in time but you could render out the particle movement as well.
You won't successfully accomplish this effect with just two layers, even using a 3D app to create your shattered glass. You'll need at least three or four. Your footage of the iPad, footage of the glass that you motion track to the iPad screen (Mocha is your best friend here) and layers for the parts of the glass that fly out. To enhance the effect and make it more realistic you'll need a layer for reflections of the scene in the glass you are going to shatter, reflections in the flying pieces of glass, shadows, and displacement layers to add realism to the larger bits of glass that fly out when the screen shatters.
I've seen several iPad and smart phone shattered screens and, fortunately for you, pieces don't fly out because it's safety glass or at least pseudo safety glass because the membrane that is used for the touch screens keeps the chards together. You don't need to have pieces fly out to make it look real.
Personally, I'd shop around (or ask around) for a faulty iPad. You should be able to find someone with a dead iPad 1 or iPad 2 fairly easily. I would expect you could buy something like that for $50 or less.
Then just shoot the real thing, preferably at a high frame rate. You may choose to enhance it at a later stage in AE, but the primary shatter will be realistic.
I agree with Andrew: practical effects are always the best effects. They look real because they ARE real.
But take precautions! Do a boatload of trial runs with a standin prop until everything is just right and you KNOW how it's going to behave and look on camera when you shoot it for real.