DSLR Camera and Interchangeable Lenses?

What is a good DSLR camera with fast shutter speed?
Can lenses fit on a camera even if it is a different brand as long as the mm matches?
Ex. Can a Canon 18-55mm lens fit on a Nikon camera with 18-105mm?

Added (1). Asg?

Added (2). Thanks. I was just using Nikon and Canon as an example. I have lenses but can't find the camera brand anymore so was wondering if they could be used on different brands (like the Canon/Nikon example)

Here are the current entry level cameras from Nikon and Canon:

Nikon D3000, D3100, D5100

Canon Xs, T3, T1i, T2i, T3i

for the lenses, no. You might just destroy the camera. If you have a Nikon camera, you have to use lenses made for a Nikon system- best would be Nikkor lenses. If you use a Canon system, use Canon lenses

A shutter speed of 1/2000 is already very fast. All dSLRs go faster than that. You probably are concerned with shutter lag, the time between pressing the shutter and when the camera actually takes the shot.

Lenses only have to have the same mount as the camera to fit. Either you buy the same brand as your camera or you get a third-party lens.No. A Canon lens can't fit a Nikon lens. Compatibility is another matter.

Focal length in mm is more or less is angle of view. Different focal lengths, different purposes.

Not sure why you need a fast shuter speed camera. You know in theory, faster the shutter speed, the less clarity your image become? And most of fast shutter cameras work better with wider aperture lens to achieve the benefit. But these lens are extremely expansive.i. E. Canon 85mm 1.2L cost $2000+.

Rebels are nice. If you get a camera and want to use a differnt brands lenses just get an adapter. Also sony just came out with a camera that while technically is not a dslr it performs just as well as any entry level dslr would but the mirror is replaced by a large sensor.

its called nex5 check it out. I just picked one up yesterday. They are pretty cheap and there are quite a few lenses being released for it.nex 5 can take 7 shots a second (good for capturing motion as if were still)

I suspect that is what you are after… However if you are looking for some cool artistic blur shots then you can still slow it down, no prob.

All DSLRs have fast shutter speeds. As keerok suggests, you might be interested in low shutter lag, which still covers most DSLRs (unless you're trying to shoot in low light with autofocus, which can stall even the best cameras).

The "mm" number refers to the lens' *focal length*, which has nothing to do with which cameras that lens can be attached. (In your example, you're technically asking if a lens can be added to a camera that already has a lens attached, which is a definite no.) A DSLR can use lenses of any focal length.

The only major consideration is if the camera body and lens share the same *lens mount*. You can use a different brand of lens and body so long as they use the same lens mount (with some very unlikely exceptions). Sometimes there are lens mount adapters available for specific combinations of body and lens, but you're much better off getting a lens made for that camera's mount.

Also keep in mind that some companies only make lenses for other camera brands. For instance, both Tamron and Sigma are well-known "third-party lens" manufacturers, providing lenses for Canon EF, Nikon F, and Four-Thirds mounts.

You can show your lenses to a camera shop to see if they can identify what mount it uses.

["asg" roughly means "I don't care about your problem; I just want 2 more points to ask more stupid questions."]