(This is another post based on something I wrote elsewhere as a response to a question about this lens – I’m re-sharing it here with minor editing.)

I’ve used the Canon 100-400mm f/4.5-5.6L IS lens  a lot – for things as varied as handheld shooting of bicycle races and tripod-based landscape photography. Over time I’ve developed a few thoughts about the performance of this lens and some of the comments that I frequently hear and read about it.

First, especially from my tripod-based work, I have found that the lens is capable of very good performance in terms of image quality – e.g. “resolution.” This is true at all focal lengths, but more so perhaps at some than at others. To give one example, I also own the f/4 IS 70-200mm lens. At one point I tended to always switch to the shorter lens when shooting in the range up to 200mm, concerned about a potential sharpness hit with the 100-400. Over time I figured out that while the 70-200 is probably a very tiny bit sharper here, in most cases the difference in many kinds of shooting is insignificant and invisible in real-world output – and in many cases where I would have switched lenses I now leave the 100-400 on the camera. Continue reading Thoughts About the Canon EF 100-400mm f/4.5-5.6L IS Lens →