Do you have to use camera lenses that are the same brand as your camera?

If I got a canon slr, could I use my friend's nikon lense?

As others have already written, it is possible to use Nikon lenses on a Canon camera with an adaptor. But you are unlikely to get 100% use from the lens. Not all of the features of the lens may work - including VR vibration reduction, autofocus or even light metering.

Unless the Nikon lens you want to use is a pricey one, you would likely do better to spend the money towards buying the equivalent lens for your Canon.

There are 3'rd party companies that make lenses to fit other camera brands - companies like Tamron, Sigma and Tokina. But you must buy the correct model of their lens to fit your camera. So a Sigma lens made for Canon will only fit Canon.

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http://www.lenslenders.com

No you do not to use the same brand lenses but you do need the right the right mount on a lens so it can hook up to the camera body.

As long as the lens fits, the brand doesn't really matter.

The lenses do not have to be the same brand but it has to have the same mount ... adaptors can b bought to convert lenses .. If its a newer camera with power zoom and focus then that might be a problem because the electronics may not work .. cannon and Nikon do have a different mount so with out the proper adaptor you can't use it .. I saw one on EBay for $180.00
You might be able to pick up a cheap used lens for your cannon . with digital camera's coming down in price people are not using or getting rid of their 35 mm slr's so I'm sure you could find a deal somewhere

Why not get a Nikon SLR