I have been using a Nikkor 24-50mm AF zoom since 1990. Back then, a friend of mine who also has one of those told me that it had some distortion at the 24mm end. I never noticed it myself until recently when I shot some landscape images and placed the horizon near the top of the flame. My slides show very noticable barrel distortion with a curved horizon.

I am wondering whether the Nikkor 24-120 zoom and the 20-35 zoom have similar problems or not. If I want to avoid such distortion, do I need to get a fixed focal-length lens?

-- Shun Cheung (shun@worldnet.att.net), January 26, 1999

Answers

It is a giving fact that wide angle zooms are prone to distorsion. It is extremely difficuls for the manufacturers to construct this type of lenses. The construction of this type of lenses were avoided in 70ies and 80ies by many manufacturers. I own the 24-50 also and I know its shortcomings. Therefore it would be better to have a 28-70/85/105 completed with a fixed 24 or 20.

-- Ivan Verschoote (ivan.verschoote@rug.ac.be), January 27, 1999.

What Ivan said is true. There is certain to be some degree of distortion in WA lenses. This is especially so in zooms. The 24~50mm is a good lens.

I have the 20~35mm f2.8 which I consider a very good lens. It does exhibit some distortion but you can minimise this by the way you position yourself and the distance of the subject from the camera.

-- Alan (afive@pacific.net.sg), January 27, 1999.

I have the 24-120 and it also has noticeable distortion for linear objects placed too close to the frame edges. A fixed focal length wideangle will greatly minimize, but not eliminate the distortion.

-- Barry Schmetter (bschmett@my-dejanews.com), January 27, 1999.

Your zoom may have barrel distortion at 24mm, but your test doesn't prove it. The horizon is actually a circular object. If it was at the top of the frame, on a wide angle, you would see the curve.

If you want to test for barrel or pincushion, you should use a test target or building, anything with straight edges.

-- Alan Gibson (Alan.Gibson@technologist.com), January 27, 1999.