Product Description

20mm wide angle lens for Canon cameras

Product Details

• Brand: Canon
• Model: 2509A003
• Dimensions: .25 pounds

Features

• EF mount; wide-angle lens
• Floating system; inner focusing; full-time manual focus
• 20mm focal length
• f/2.8 maximum aperture
• Ring-type UltraSonic Motor (USM)

Amazon.com Product Description
Wide-angle lenses let you capture more of the image by broadening the angle of view and increasing the depth of field, thereby bringing more of the area into focus. The lenses also provide a unique perspective by expanding the apparent distance between the foreground and the background. This Canon 20mm f/2.8 is no exception, with such additional features as a floating rear focusing system with an Ultra Sonic Motor (USM), a 0.8-foot close focusing distance, and a 94-degree diagonal angle of view. As with all Canon lenses, the 20mm lens carries a one-year warranty.

Specifications

• Focal length: 20mm
• Maximum aperture: f/2.8
• Lens construction: 11 elements in 9 groups
• Angle of view: 94 degrees
• Focus adjustment: Rear focusing system with USM
• Close focusing distance: 0.8 feet
• Filter size: 72mm
• Corresponding mounts: Canon
• Dimensions: 3.1 inches in diameter and 2.8 inches long
• Weight: 14.3 ounces
• Warranty: 1 year

From the Manufacturer
Ultra-wide-angle lens for serious applications. Easy to hold and carry at 14.3 oz. (405g). Floating rear focusing system. Sharp images are obtained at all subject distances.

The optical performance, fast f/2.8 speed and ultra-wide-angle coverage make this a great choice for many applications, like interiors, scenics, travel and photojournalism. It uses a "floating" optical system for excellent sharpness even at its minimum focusing distance of under 10 inches (0.25m), and with a ring-type USM and full-time manual focusing capability, offers the speed and handling pros expect.

Wide and Fast
If you need an ultra-wide angle and a large aperture, one of the following lenses will fit the bill. Ultra-wide-angle lenses can capture scenes beyond your natural field of vision. The EF 15mm f/2.8 Fisheye, the widest of them all, has a 180° angle of view. For more normal-looking wide-angle shots, there are longer wide-angle lenses up to 35mm with the maximum aperture you need.

Customer Reviews

Lens
Always happy with Canon Lenses.. I am more a detailed photographer, I purchased this mainly for my husband. He enjoys taking more landscape photography. Overall, very happy!

Great, versitile lens
I was a bit concerned at first with the fixed focal length, but it has proven to be very versatile. It takes very sharp pictures, even when fully opened in low light. I have not noticed any of the vignetting that other users have mentioned.

Bottom line: great wide angle lens for the price. Useful for landscapes and tight space, low light situations.

disappointing, especially for a fixed lens
This is one of the first two lenses I bought when I switched to a Canon SLR about five years ago. I've had plenty of opportunity to use it since then, both with film and (full frame) digital.

The idea behind this lens is a good one -- 20mm is wide enough to allow for landscape and architectural photos, and it focuses close enough for entertaining photos of people's faces, taken about a foot away from their noses (note that you'll need either a ring light or lucky ambient light to pull off the latter). There is some pincushion distortion, but nobody would accuse the results of looking like a funhouse mirror, as would be the case with a fisheye lens, for example.

f2.8 is fast enough; I've no complaints there. Unfortunately, this camera consistently vignettes -- the corners of every image are dim. This is true even with a bare lens, and filters make it worse. You can correct the problem in image editing software, or just crop the image, but what's the point of buying a 20mm lens if you're going to have to crop every photo you take with it?

If this had been a cheap zoom lens, I'd have expected the problem and not been bothered by it. With a fixed lens, however, I think there isn't much excuse.

Canon still charges about the same ($400) that I paid for this lens years ago. By now, they ought to have upgraded this thing, or dropped the price. It is the worst EF lens I own.


-- addendum: I've recently been using a Canon EOS IX, which takes APS film. This lens is much more useful with that camera, though using even APS-H, you get something akin to the image you would get from a 35mm lens on a 35mm negative.