"After a couple of weeks with this lens on my Canon 40D, I like it more all the time. I've found that the sweet spot on mine, aperture-wise, is about f/22. That gives me the most DOF and clarity combination for 1:1 macro shots. I would have loved to be able to use it at it's full f/32, but my test shots with it show that 1:1 shots at that aperture lack the clarity I'm trying to achieve in my macros.

Extra light is a must if you want any DOF to speak of, so if you don't have a ring light or other ways to deal with it yet, you'll want to keep in mind that there's a cost associated with that aspect of this as well.

As a 180mm prime lens, it performs well outside of the macro range too. I'm getting good, crisp shots throughout, and the AF works pretty fast.

It must be compared to the Canon 180mm macro lens, as that's really what it replaces. For that, all I can do is point to the many reviews on the net, as I don't have the Canon. I bought this after slogging through those reviews and finding most all of them favorable towards this lens as a great alternative to save money and still get a great shot - Maybe not as great as the Canon, but not generally enough difference to matter. "

    "I've only had this lens for a few days, but I am happy with it so far. Could even capture two ants attached to the wing of a butterfly. Getting close, as in the 18" minimum distance, works as described. Auto-focus does hunt a little when close to object, had to manual focus. Great lens for the money. "