Does APS-C have lower resolution?
 

I just wondered, because of the crop factor, does the Canon have a lower resolution than the 5D? It makes sense to me that, by "zooming" in on the image of the mirror 1.6x, it'd have less definition.

re: Does APS-C have lower resolution?
 

Resolution is the same.

re: Does APS-C have lower resolution?
 

I think you're mixing a few things up there.
There is probably some relationship between resolution and sensor size. But in the sense I think you're talking about there isn't a direct relationship. If an APS-C size sensor has a lower resolution than the 5D it's because the sensor itself has fewer pixels. It's not necessarily related to size.

The crop factor is not a case of zooming in as such, but a way of accounting for the sensor's smaller field of view. Most of the way we comprehend the focal length of a lens is in relation to a 35mm image. When people think of, say, a 50mm lens they have an idea what sort of field of view you are going to get from that already. But that is only true on a 35mm camera. Canon APS-C is, I think, about 22mm. So using a 50mm lens on that will have a smaller field of view than it would on a 35mm. The ratio of 1.6 tells you roughly which focal length would achieve the same field of view on a 35mm camera (so a 50mm lens on an APS-C has roughly the same field of view as an 80mm focal length on a 35mm camera).

Hopefully that makes sense. Clever people will surely be along soon to point out where my terminology is messed up.