Canon digital camera and other non canon lens?

I have a Canon Digital Rebel XT and I was wondering what other kinds of non canon brand lenses can I use with my camera? Currently I use a Canon 50mm 1.8 and the 18-55mm kit lens.

Some lenses to consider are those from Sigma, Tamron, and Tokina. On average, each lens does not do as well as their Canon or Nikon counterparts, but still get the job done. If you want quality, get Canon lenses. If you want a cheap alternative, go to the third party brands.

As for specifics, I use a Tamron 70-300mm f4-5.6 at the moment, but am going to upgrade to a 70-200mm VR once I save up enough money. The Tamron is good for the money, but slow to focus. I hear this also plagues the type with the built in motor.

The type of lens you want depends on the type of shooting you're going to do. If you shoot landscapes, look into a wide angle lens, such as the Sigma 10-20mm or Tamron 17-50mm. For telephoto zoom, the 70-200mm f2.8 Tamron would be a good option. I don't care too much for the Sigma, because there are issues with the outer coating. For portrait work, I've heard good things about the Tamron 90mm macro, or the Sigma 70mm macro. I have not used Tonkina, but some people say they are good, while others do not. I guess the same goes for Sigma, but not so much with Tamron.

Don't do it ... buy used Canon's if you have to but you will be unhappy in a couple decades with the non-Canon lenses.

If you really HAVE to buy a non-Canon lens ... look at the Tokina line .. they are the ones who make some of the Pentax lenses as well as the Hoya filters

There are many other brands you can use. Some examples are Sigma, Tamron, Tokina. These companies manufacture lenses for most major brands of cameras. Some of these lenses are decent but you will be much happier in the long run if you stick with Canon lenses.

If you are planning on buying a non Canon lens make sure you specify that you need a Canon mount. Every camera brand uses a different system to mount their lenses to the camera.