Bests & Worsts Reviews from Amazon

For APS-C digitals cameras with a 1.6 crop factor, this becomes equivalent to 44mm with a 35mm film camera. I bought this lens a general purpose prime lens for APS-C with roughly the same angle as 50mm for the 35mm film camera (Canon does not have a 30mm, only Sigma's 30mm f/1.4 is the closest). I have used this prime lens on my Digital Rebel and 30D for a few hundred shots so far, and I am very pleased with the sharpness of the photos, as well as the speed. I think it is softer at f/1.8, which happens in most cases of any lens, and rather like to used a little to f/2.2 - 2.8. With such low apertures the area of focus is very shallow, thus I appreciate the great autofocus from the USM, which works flawness with the combination of a Canon digital SLR and a Canon lens. Also there are 10 glass elements, producing a nic bokeh, minimum distance of 25cm for focusing, so it is well-built lens. It is about 10 oz, not as light as the f/2.8 version, but it is much stronger in low-light situations, and when used at f/2.8, the f/2.8 version shold be much sharper. It is not an L lens (these are so expensive, and also heavy), but is exceptionally good in the non-L lens category, especially for the APS-C camera's. For full size APS sensors, the 50mm f/1.4 would be the choice, but if you use the 50mm in APS-C systems, the crop factor makes this a medium telephoto 80mm equivalent lens, not good for general purpose shooting. It is realively higher in price to the f/2.8 version. The reasons I chose this f/1.8 version was because of the following: 1. low-light shooting in the f/1.8-2.5 range 2. USM for fast, quiet, and accurate autofocus, espcially helpful targets are moving 3. Nice soft bokeh per Canon (I like it so far). 4. Can use as wide-lens in full-size APS sensors the future if digital SLRs would gradually shift in that direction. It depends on the type of situations you plan to shoot photos, but I think if you need such features, this lens is very much worth the price.