Is the question of wave distortion in modern 35mm wide angle retrofocus lenses a non issue these days?For the purposes of general photography emphasis both by designers and evaluators appears to center on the minimisation of vignetting.Is the issue of wave distortion only for professional large format architectural photograhers who use contemporary Super Angulon non retrofocus lenses which render straight lines as absolutely straight. For my part,whilst taking interiors and architectural subjects my compact 3.4 S.A. suitably stopped down, gives commendable results.Having not used an aspherical 21mm I cannot comment on it's characteristics up close.

-- Sheridan Zantis (albada60@hotmail.com), September 04, 2001

Answers

Wave distortion (AKA Poirot's mustache distortion) is definitely better than it used to be. I had an old 60s era Nikon 24 that had distortion like a roller coaster. My recent Nikon/Leica-M 20/21s have had nothing so severe. My Leica 21 is the NON-ASPH f/2.8 (slight retrofocus design to clear meter cells). I have noticed no distortion with it, but I haven't done any architecture shots with things lined up - usually everything is tilted in my shots. I will experiment.

-- Andy Piper (apidens@denver.infi.net), September 04, 2001.

To answer your question better - I'm sure distortion is important - but it's less of an issue because it's better corrected even in retrofocus lenses. It is more of an issue shooting architecture with ANY format, and not much of an issue for documentary/journalistic photographs, regardless of format. A lot of people love the 21 S.A. even if they don't care about distortion.

I'll still experiment with my Elmarit and see what it's doing...

-- Andy Piper (apidens@denver.infi.net), September 04, 2001.

Sheridan: I haven't experienced any problems in practice, with architectural subjects, from wave distortion. Granted, the 21mm SA and also my 38mm Biogon are excellent, low distortion lenses; but in architectural shots with them, there is still (necessarily) a perspective alteration, increasingly evident as the subject appraoches closer to the corners of the frame. Round objects near the corners become stretched out of shape. The upper corner of a building begins to loom forward, stretched out of square. This doesn't necessarily make the picture displeasing, and I think it's a more significant casue of distortion than the characteristics of retro lenses. I see nothing to complain about with my 28mm Elmarit, or my 35mm shift Nikkor, both retros.

Regards,

-- Bob Fleischman (RFXMAIL@prodigy.net), September 04, 2001.

Sheridan:

For what it is worth, I tested both a 21pre-asph Elmarit and 21asph Elmarit for linear distortion, and found none noticeable in either lens. I performed the test at 2 meters (approx 100x focal length).

-- Jack Flesher (jbflesher@msn.com), September 05, 2001.

I just looked at some current charts from the Zeiss folks...the lowest distortion photography lens they offer is - not a Distagon, not a Biogon (sorry Bob!) but the - Hologon-G 16mm for the Contax G1/G2. With LOTS of vignetting. Designed in the 1990's (but based on a 50s/ 60s original design, which was in turn related to the Goerz Hypergon layout.) So someone is still emphasizing linear correctness.

-- Andy Piper (apidens@denver.infi.net), September 05, 2001.

I just looked at some current charts from the Zeiss folks...the lowest distortion photography lens they offer is - not a Distagon, not a Biogon (sorry Bob!) but the - Hologon-G 16mm for the Contax G1/G2. With LOTS of vignetting. Designed in 1994 (but based on a 50s/ 60s original design, which was in turn related to the Goerz Hypergon layout.) So someone is still emphasizing linear correctness.

-- Andy Piper (apidens@denver.infi.net), September 05, 2001.