Canon EF 2578A002 70-200mm f/4 USM Lens

This is one of Canon's best lenses. It is not as wide open as the 2.8, but it still workd beautifully for most purposes. It's construction is superb. The controls are nicely damped, and it feels wonderful. It is a fairly heavy lens, but that means that it is full of good glass. The UD elements mean you get less chromatic abberations. I have noticed some if you get too much contrast --like a sunset behind snowcapped mountains. I've gotten some color separation around the outlines of the mountains. As good as the lens is, think how bad it would've been with a lesser lens. The aperture is great at a consistent f/4. It makes it a bit slow for indoor sporting events sometimes, but if people are moving ar normal non-running speeds then it excels. The IS is the best Canon makes at a vibration reduction of up to 4 stops. (NOTE: To get the last stop you have to hold the shutter down halfway for a second or so before you take the actual shot. I guess the gyro has to speed up a bit more). This is widely considered to be one of Canon's sharpest zoom lenses. It is incredible from f/4 up to about f/22 with the best being the usual 8-11 range. This lens is so sharp that it resolves more light than a camera can see. Few zooms reach that level. It works great for portraits, crowd shots and people of all sorts. It would be nice to have that extra stop down to 2.8 to get the extra blurry background (bokeh). But the color reproduction is simply amazing. You have to try it to believe it. Once you have seen it you, too will be addicted. I also like taking shots of architectural details. Instead of just a landscape, take pictures of smaller details. For most sporting uses it also works beautifully. The professionals have lenses that cost up to $8000 or $9000 but this can actually compete with them! It obviously doesnt't have the razor thin depth of field that the professionals have, but I love it so. The only real downside is it's "presence," I'll call it. It is a big lens. It's also a white lens. People know when you point this thing at them. It can make people a bit camera shy. It's a little obvious and could make you stand out to thievery minded people. Pros: Vivid color Tack sharp Great zoom range Best Image Stabilization Best portraits in a zoom Bokeh Cons: Pricey It's white. Summary: Whenever I look through my photos the ones that stand out the most invariably come from this lens. I love that this lens makes me look like a better photographer than I have any right to be.