Super sharp and the focusing is faster than any lens I've ever used

if you need the wide aperture and take pictures of sports events with low light or at your kids school play this lens is awesome - super fast focus and great low light shots

This lens is supperb: sharp, fast focus, manual features.

The focus is FAST and dead on, no microadjustment needed

This iteration is even sharper, faster focusing, and more conducive to wonderful photographs

actually isn't unless you have a 2.8 fast focus telephoto.

You need the fastest focusing performance available for sports or otherwise

Fast, accurate focus is key and this performs the best of all the lenses I own.

This lens has some key features, including a zoom ability that doesn't change the length of the barrel, the ability to override the autofocus on the fly without turning off the AF (I have a split circle focusing screen in my 50D which works beautifully with this lens, thanks to the 2.8 aperture...just like the old days), closer focus capabilities than the last version, and an even better IS system than the original version of the lens

Mounted on my 5D Mark II body, I get excellent corner-to corner sharpness and contrast backed by silent, pinpoint-accurate auto-focus

Focuses FAST - fastest focusing

Again, accurate focus and incredibly sharp pictures

Extremely sharp and crisp images, fast-steady-silent auto-focus and great in low light situation

Used for: sports photography, both indoor and outdoor (specifically soccer, football and basketball, landscape and wildlifePros: tack sharp, fast auto-focus, high aperture valueCons: heavy, cost

I could probably try shooting even slower and still get sharp focus

Hike up the aperture somewhere between a 4 and 8 and most of the subject is in full, tack sharp focus

The tack-sharp focus, at all lengths and apertures, is amazing.

In order to make a final decision I rented a copy for a week and was very impressed by the sharpness, extremely quiet IS and very fast auto-focus

If is very fast focus, stable and just as good at F2.8 as any other aperature

Exceptional image qualityHighly effective image stabilizationExcellent autofocus and manual overrideVery accurate focusing ,very fast ,excellent color and contrast.

Low chromatic aberration, very sharp, excellent contrast, and very quick focusing

It's fantastic for portraits I even sold my slow 85 1.2 because in my opinion this does what that does and more , just as good bokeh but better auto focus and even though it's just as heavy the 70-200 is more ergonomic.

Paired with my 7D and no micro-adjustment needed I have unbelievable tack sharp images and much faster focusing

My first copy that I received was soft focusing, however when I called Amazon

This lens has some key features, including a zoom ability that doesn't change the length of the barrel, the ability to override the autofocus on the fly without turning off the AF (I have a split circle focusing screen in my 50D which works beautifully with this lens, thanks to the 2.8 aperture...just like the old days), closer focus capabilities than the last version, and an even better IS system than the original version of the lens

Very fast focus able to capture birds mid flight (7D) and nice bokeh

I just noticed however that what was a perfect focus is no longer

Case in point, the new PS smart sharpening and camera shake reduction works amazingly well with soft focus and the shake.

This lens is the complete package - razor sharp, fast focusing, great IS

Nice and crisp, easy focusing

Fast focus

Whisper quiet focus motor and very fast to focus

Excellent focusing, clean crisp images.

The fast focusing of this lens and image stabilization makesshooting moving objects a breeze

Nice background blur - because of the long focal lengths and large maximum aperture, throwing things into soft focus in the background is one of the strengths of this lens

The focusing is fast, the pictures are sharp and it's really quiet

The ring provides excellent manual focusing fidelity, with a slightly smooth resistance and plenty of travel

The speed of the auto focus and the smooth manual focus ring was major improvements for me.

Very shar, fast focusing

This lens is incredibly sharp, fast focusing, has great contrast and an awesome IS system

The fast focusing of this lens and image stabilization makesshooting moving objects a breeze

the focus is pin point accurate, so much that 95/100 pictures will be in focus

Sharp, focuses quickly, the stabilization works, and you'll feel like a boss.

I had the first version of this lens, and it didn't change focus at different focal plains like the new version does.

Many lenses - especially faster lenses - tend to be a bit clunky when focusing.

the f/2.8 is as sharp as the f/4

the f/2.8 is as sharp as the f/4