Canon Digital SLR Camera and Lens Reviews! The-Digital-Picture.com. A great site that seems to review just about every Canon lense. Here's a quick overview of the top lenses and some good "general recommendations":http://www.the-digital-picture.com/Canon-Lenses/Canon-General-Purpose-Lens.aspx. The folks at "Fred Miranda":http://www.fredmiranda.com/reviews/showcat.php?cat=27 also have a great list that correlates to Digital Picture.

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(l-to-r) EF 28-135 F/3.5-5.5, EF 17-40 F/4 L, EF 24-105 F/4 L, EF 24-70 F/2.8 L

The basic recommendations for full frame cameras like the 5D are:

* "Canon EF 24-105 F/4 L IS USM":http://www.the-digital-picture.com/Reviews/Canon-EF-24-105mm-f-4-L-IS-USM-Lens-Review.aspx. As an alternative, this lense is slower, but has a wider range. Good for DX sensors with 1.6x factor since 105mm is more like 160mm equivalent on a full frame. If you can afford this, this is a nice lense for more zoom and it is image stabilized. Best choice if you only have one lense. It is 1.5 lbs and 4.2" long, so it ain't small, but it is very functional although expensive at $1200 according to "Pricegrabber":http://www.pricegrabber.com/p__Canon_EF_24_105mm_f_4_L_IS_USM_Standard_Zoom_Lens,__11402001/sort_type=bottomline * "Canon EF 24-70mm F/2.8 L USM":http://www.the-digital-picture.com/Reviews/Canon-EF-24-70mm-f-2.8-L-USM-Lens-Review.aspx ("Fred Miranda":http://www.fredmiranda.com/reviews/showproduct.php?product=5&sort=7&cat=27&page=1 9/10). This is the one lense that does it all but costs$1100 ("Pricegrabber":http://www.pricegrabber.com/search_getprod.php/masterid=864627/sort_type=bottomline). Not too big particularly and good for full frame and DX sensors. The image quality is very good and it is very fast. A better choice than the lense above if you do lots of low light and available light shooting and don't want a flash. Quality-wise, it easily beats the lower grade EF 24-85 and EF 28-135IS. It is an "L" lense which means high quality in Canon speak.

If you have a small sensor DX camera like the Digital Rebel XT, then you need something that is more wide angle. Here are two choices that compete with each other. The F/2.8 and the F/4.0 lenses listed below:

* "Canon EF 16-35mm F/2.8 L USM":http://www.the-digital-picture.com/Reviews/Canon-EF-16-35mm-f-2.8-L-USM-Lens-Review.aspx ("FredMiranda":http://www.fredmiranda.com/reviews/showproduct.php?product=2&sort=7&cat=27&page=1 8.9/10). This is a cheaper lense with F/2.8 is ideal for indoor available light. It is expensive and heavier, but it is best if you are doing lots of available light shooting. It's fast so its expensive at $1300 ("Pricegrabber":http://www.pricegrabber.com/search_getprod.php/masterid=533991/sort_type=bottomline) * "Canon EF 17-40mm F/4.0 L USM":http://www.the-digital-picture.com/Reviews/Canon-EF-17-40mm-f-4.0-L-USM-Lens-Review.aspx. This is the moderate price high quality lense. Get this if you don't need available light shooting or lack the bucks to pay for the F/2.8. ($670 at "Pricegrabber":http://www.pricegrabber.com/search_getprod.php/masterid=815192/sort_type=bottomline)

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EF 1.4x Converter, EF 16-35 F/2.8L, 135 F/2.0, 24-70 F2.8L, 702-200 F/2.8L

If you really want to go light on a Rebel or EOS-30D, then you can consider a dedicated EF-S lense. This won't work with a full frame, but it is much smaller and lighter:

* "Canon EF-S 17-55MM F/2.8 IS USM":http://www.the-digital-picture.com/Reviews/Canon-EF-S-17-55mm-f-2.8-IS-USM-Lens-Review.aspx. This is the small frame version and it is a fixed F/2.8 aperture like its "L" lense cousin. $1200 at "Pricegrabber":http://www.pricegrabber.com/p__Canon_EF_S_17_55mm_f_2_8_IS_USM_Lens_for_Canon_DSLR_Cameras,__19432409/sort_type=bottomline !http://www.the-digital-picture.com/Images/Other/Canon-70-200-Size-Comparison.jpg! 24-70mm f/2.8 L USM, Canon 70-200mm f/4 L USM, EF 70-200mm f/2.8 L IS USM Finally for either small sensor or full frame, consider getting a zoom lense. The 70-200 is the most popular size and Canon makes three to consider: * "Canon EF 70-200 F2.8 L IS USM":http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-2.8-L-IS-USM-Lens-Review.aspx. This is the biggest and most expensive, but with image stabilization plus being very fast at F/2.8, it is really useful for lower light and most flexibility. I have the Nikon 70-200 VR equivalent and it is pretty amazing what image stabilization can do. It gives you three stops of advantage. The main drawback is the$1700 price and the fact the lense is just titanic in size.
* "Canon EF 70-200 F4.0 L USM":http://www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-4.0-L-USM-Lens-Review.aspx. Combine this lense with either of the two above and you have a complete kit. Unlike Nikon, there isn't an equivalent to the very cool 12-200MM F/3.5-5.6 lense that the D200 shipped with. That is an awesome 12x zoom in a single lense. The 70-200 is a great value in high end L lenses. It is the smallest compared with the EF 70-200 F/2.8 L which is much larger because it has a bigger aperature. Then there is the really big "EF 70-200 F/2.8 L IS USM": at $1700 ("Pricegrabber":http://www.pricegrabber.com/search_getprod.php/masterid=588161/sort_type=bottomline) which is much like the monster Nikon 70-200 ED-IF VR with image stabilization. It is good for portraits, sport photography, although it is too slow for indoor or heavy overcast days since it is relatively slow. It's relatively inexpensive at$600 at "Pricegrabber":http://www.pricegrabber.com/search_getprod.php/masterid=588199/sort_type=bottomline.
* "Canon EF 100-400 F/4.5-5.6 IS USM":http://www.the-digital-picture.com/Reviews/Canon-EF-100-400mm-f-4.5-5.6-L-IS-USM-Lens-Review.aspx. This is truly a bazooka best used for outdoor nature photography. It is image stabilized, \$1700 ("Pricegrabber":http://www.pricegrabber.com/search_getprod.php/masterid=430117/sort_type=bottomline).