Take one of Canon's most popular lenses, the Canon 70-200mm f/4 L , add an up-to-4-stop Image Stabilizer and you get the Canon EF 70-200mm f/4L IS USM Lens. If you don't need the subject-action-stopping and background-blurring capabilities of the faster Canon EF 70-200 f/2.8L IS Lens , this lens...

The lens focuses very fast with almost no noise. The IS function is a nice touch, but I am not sure how practical it really is. Having upgraded from an entry level lens, this lens is much heavier. Images are sharp with great color.

Consistent Output; Easily Interchangeable; Easy To Clean; Sharp Focus; Strong Construction

Slightly Heavy

The EF50/1.2L is a totally new optical design (there was an old FD 50/1.2L) and uses a molded aspheric rear element (the 50/1.0L used two very expensive ground and polished aspherics). It has a true ring type USM motor and a high speed CPU for fast focus.

Hands on

Quite simply an excellent lens. As sharp as primes in its telephoto range, great contrast and colour, and state of the art IS. What it gives up in maximum aperture to the f2.8 version can be forgiven considering it's half the weight and 2/3 the cost.

Canon EF 70-200mm f/4L IS USM is clearly one of the best EF mount telephoto zoom lenses available on the market. The lens shows outstanding image quality with particular strength in the 70-135mm range.

A compact telephoto zoom lens from Canon's 'L' series.

Excellent optical quality; Superb build quality; Very effective image stabilisation; Fast to focus; Sealed against weather and dust; Light weight

Sometime miss-focuses near minimum focus distance

I decided on the f/4. I was against the f/2.8 because it's twice the price, twice the weight and a fatter lens. (Then again, you need more glass for f/2.8...)I've been very impressed with the image quality. Every image I've taken has been razor sharp, with no noticeable CA.

Fast focusing; sharp; very lightweight; cheap alternative to the f/2.8 version if you can live with f/4

NONE

The build quality of this lens is excellent - no wobbling and smooth controls. The lens does not extend during zooming and thanks to its inner focusing system the front element does not rotate so using a polarizer is no problem - unless you attach the hood of course.

Its compact size and Light weight can be deceiving when put next to its bigger brother, But at its f4 aperture the performance of this lens is truly amazing the IS system works well Testing it i went as low as 1/13 shutter speed at 200mm with IS on and it kept on taking usable images ..

Easy to use; Compact; Build quality