The Canon EF 20-35mm f/3.5-4.5 USM Lens features a short wide angle focal
length range with decent build quality at a relatively low cost.
The Canon EF 20-35mm f/3.5-4.5 USM Lens utilizes a metal mount and has decent feel to it.
It is a reasonably well built lens.

Pictured above from left to right are the
Canon EF 20-35mm f/3.5-4.5 USM Lens, the
Canon EF 16-35mm f/2.8 L USM Lens and the
Canon EF 24-70mm f/2.8 L USM Lens.
The Canon EF 20-35mm f/3.5-4.5 USM Lens is rather small and light.
It does have a rather large 77mm filter size though.
This is good for filter sharing if you also own some of Canon's L Zoom Lenses which typically feature a 77mm filter thread.
Featuring USM (Ultrasonic Motor), the Canon EF 20-35mm f/3.5-4.5 USM Lens focuses fast and quietly.
However, I must note that I had some low-light focusing issues with this lens even on a Canon 1-Series Pro body.
The Canon EF 20-35mm f/3.5-4.5 USM Lens' aperture is medium-wide starting at f/3.5 at 20mm, quickly going to f/4 around 23mm and finally to f/4.5 at 29 or 30mm.
A 5-blade aperture produces 5-pointed OOF (Out Of Focus) highlights when the Canon EF 20-35mm f/3.5-4.5 USM Lens is stopped down.
Although I don't consider it quite as good optically as the
Canon EF 16-35mm f/2.8 L USM Lens or the
Canon EF 17-40mm L USM Lens,
the Canon EF 20-35mm f/3.5-4.5 USM Lens performs reasonably well.
It is reasonably sharp wide open and improves slightly when stopped down (narrower aperture selected).
Corners are a bit soft wide open.
Vignetting is strong at wide open apertures - especially at the widest angle focal lengths.
The Canon EF 20-35mm f/3.5-4.5 USM Lens shows some CA (Chromatic Aberration) but it is rather well controlled as is flare.
The Canon EF 20-35mm f/3.5-4.5 USM Lens' biggest problem (in my opinion) is barrel distortion on wide end
even on a 1.3x FOVCF body.
I found it to be very noticeable at 20mm and still noticeable at 24mm.
Who does the Canon EF 20-35mm f/3.5-4.5 USM Lens make sense for?
For those who are not interested in the
Canon EF 16-35mm f/2.8 L USM Lens or the
Canon EF 17-40mm L USM Lens
(price or size being the likely reasons)
and need a slightly wider angle than the 28-xx or 35-xx normal zoom they already own (or plan to buy).
An alternative for consideration would be the
Canon EF 20mm f/2.8 USM Lens.
The Canon EF 20-35mm f/3.5-4.5 USM Lens is a decent value in a short focal length range wide angle zoom lens.
Recommended Shopping Resources
(Using these links to make your purchase supports this site)
Canon EF 20-35mm f/3.5-4.5 USM Lens at B&H Photo
Canon EF 20-35mm f/3.5-4.5 USM Lens at Amazon.com
Canon EF 20-35mm f/3.5-4.5 USM Lens at Adorama (Imported)
Canon EF 20-35mm f/3.5-4.5 USM Lens at Adorama
Canon EF 20-35mm f/3.5-4.5 USM Lens at 17th Street Photo
Find the best price on the Canon EF 20-35mm f/3.5-4.5 USM Lens
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