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The beauty of a digital SLR is that it has separate lenses, and these must be purchased separately. Without a Canon Rebel lens, your new camera is pretty useless. And getting two or three (or more) lenses is even better. However, there is one small problem, and that is the huge number of choices. It can be daunting.
You can spend hours and days visiting web sites and paging through photography magazines looking to the perfect lens, and then you will probably be even more confused than when you started. You may have thought that picking out your first digital SLR was a challenge, but it pales in comparison to finding the right lenses.
Good News! There Really Are Three Top Canon Rebel Lens Choices
If you are just starting out in digital SLR photography, there is a high probability that you will be doing it as a hobby or simply to get better pictures than you could with the old point and shoot camera you are replacing. With that in mind, there are a few lenses that are wildly popular among those who are in your situation. And, even better, these lenses will not require a mortgage on your first-born.
Canon Rebel Lens #1 - The Canon EF 50mm f/1.8 II. It may come as a surprise that the first lens on the list is a single focus lens rather than a zoom lens. However, for about $100, you can't find another lens that will give you sharper pictures. It's hard to beat, even with lenses that cost $500 or more.
The 50mm f/1.8 has some exceptional benefits. In addition to the super sharp images it produces, it also features an extremely wide aperture at f/1.8. This means that you can use the lens in very low light areas, like kids performances where flash is not appropriate. The wide aperture also makes it one of the best choices for taking portraits. It produces the nice blurry background that is so highly desired for that type of photography.
The one drawback is that it is made of plastic. You can't expect it to survive a 4-foot fall to the concrete (personal experience, folks). But, if you take care of it, it will give you a long life of great images.
Canon Rebel Lens #2 - The Canon EF-S 18-135mm f/3.5-5.6 IS UD Standard Zoom Lens - That's quite a moniker! How would you like to have a name like that? EF-S lenses are made specifically for cameras like the Canon Rebel T3i. This one is really well-liked by those who have taken the time to comment on its usefulness at the online marketplace.
The benefits of the 18-135mm include being able to take wide angle shots using the short end (18mm) of the zoom range and taking telephoto shots at the long end. Zoom lenses are quite handy for a variety of photo opportunities. And did you notice the 'IS' in the name? It stands for Image Stabilization, and it is very handy for getting shots that are less blurry when you don't have a tripod handy and there is not enough light to use a wide aperture. Overall, this is an excellent lens for most of your photographic needs.
Canon Rebel Lens #3 - The Canon EF-S 18-200mm f/3.5-5.6 IS Standard Zoom Lens - If you can only get one lens, consider this one. It is one of the hottest lenses available right now. Again, it is an EF-S model so it is built especially for your Canon Rebel T3i. The zoom range is amazing at more than 10X. Usually when you have that much of a range, the image quality suffers due to the technology necessary to get the extreme ends of zoom.
Another benefit in addition to the zoom range is the aperture. Other similar lenses have a smaller aperture at the longest end of the range. Even at 200mm it has the same aperture as the 18-135mm lens above. It has a fast auto focus system as well.
So, now you have your choices narrowed to three. You may ask, 'Are there better lenses for my camera?' Of course there are, but these are the best for a beginner with a limited budget. There are plenty of specialty lenses as well. So, if you are into wide-angle landscapes or macro (close-up) photography, you will want to look into the choices for those types of photography.
Best of luck in your photography future. There is no doubt that you will have some excellent images in your portfolio very soon.