First I'd like to say that I checked out many different macro lenses before purchasing this particular lens. If I didn't have someone I could borrow from, I rented a lens from LensRentals.com. That being said here's my take on the lens.

Exellent value for great macro ability and portrait work. Canon delivers with this lens.

Sharp images; great depth of field and bokeh

The lens is heavy and kind of long; No image stabilization

This is a pretty decent lens for the money. I wasn't sure how much I'd use it so price was important to me. So far so good. Easy to use, lightweight, sharp. I'd recommend it to anyone who doesn't want to break the bank but wants a good macro lens.

Lightweight

"""So You Want To Major In Macro"" Then this is the Lens for you. I am absolutely in LOVE with this Lens! Crisp, Clear and to the POINT...This lens really promotes the beauty of Macro and affords me the opportunity to truly Explore my Passion for Macro Photography!!! Well Worth The Investment!!"

I am considering buying this lens and you can buy this lens all day long from other well known retailers for $599.99. I was hoping these people here would be at least the same as these other retailers maybe even cheaper but as we can see they are alot higher not only on this lens but I've noticed...

Super sharp images and saturated colors right out of the camera. The flower image accompanying this review was of a gooseberry blossom less than a half-inch long. If I had done more research, I would have noted the IS version of the lens, and probably gone for that, but I stick with a tripod almost...

This lens has blown me away. It is my first IS lens from Canon. I own a 85 1.2L and it is slow to focus and forget about hand hold as it has no IS. This 100 2.8L macro is super sharp, fast auto focus and accurate as well.

Consistent Output; Durable; Easily Interchangeable; Fast; Fast / accurate auto-focus; Hand hold with ease; Lightweight; Manual focus feels good; Manual focus override; Nice Bokeh; Rugged; Strong Construction; Very Sharp

NONE

I am a wedding photographer and this lens does a great job at details, like rings. It is so crisp, and you can get in close. It is great!

Consistent Output; Durable; Easily Interchangeable; Sharp Focus; Strong Construction

Heavy

I chose this lens over several more expensive models based on test reports, user reviews and, above all, price. While it may not have the build quality and weather sealing of those more expensive models, it still feels quite well built.

[...]The lens itself feels well built and quite sturdy. The 2.8 aperture is a very welcome feature as this allows for relatively low light work and the minimum focussing distance means that you can get very, very close to your subject.

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