JD found these unused words:
Sir F. A. Rien wrote:
John Stafford found these unused words:
Such distortion is quite common to zoom lenses and cheap wide-angle lenses. Wide lenses without such distortion are, for the most part, terribly expensive.
"For the most part" ???
Are there -=any=- wide angle lenses that are ‘flat field’?
AFAIK, it’s a function of optics until you reach about 60 mm [35mm equivalent].
When I used film and shot interiors and exteriors, I had a Nikon 20mm lens that had no distortion. ff you put the film plane parallel to the building or interior, everything on the very edge of the shot was square, straight up and down, top and bottom. It was a very nice lens!
I think you’re confucing perspective with barrel distortion. One is a function of angle/distance relative to parts of the subject, the other that of optics.
Even a 100mm lens will produce perspective distortion unless the two planes
[subject & film] are parallel.
They still make it:
AF NIKKOR 20mm f/2.8D
"Close Range Correction for distortion-free pictures as close as 0.85 feet." $564.95 at Amazon.
Darn cheap for a great Nikkor … but wait …
<
http://photo.net/equipment/nikon/20-2.8> ‘fragile’ ???
<
http://www.slrlensreview.com/web/nikon-slr-lenses-40/wide-an gle-slr-lenses-64/95-nikon-af-nikkor-20mm-f28d-lens-review.h tml>
"The build quality of the lens is pretty decent but not spectacular – barrel is made of hardened plastic. The aperture ring is also plastic, while the narrow focus ring is rubberized."
"The lens fell prone to pretty nasty flare and aperture ghosting, both of which can be seen in the image below."
"Nikon AF Nikkor 20mm f/2.8D showed mixed performance in the lab when used on a native F mount full frame Nikon D3. Center performance was quite good in general, with already solid image quality at f/2.8 and even slightly improving with stopped down aperture. Unfortunately, border qualitysuffered quite noticeably, especially with wider apertures. At f/2.8 and f/4 border quality was mediocre at best. Even f/5.6 did not bring much improvement – borders here were kind of average. Quality finally reaches good levels around f/8, but this is a little bit too little and a little bit too late. Conclusion? Not what I’d normally call a good performing lens – based on the MTF results, AF Nikkor 20mm f/2.8 would fall somewhere in the second tier group"
"When compared to all other ultra to moderately wide angle lenses (18mm to 28mm) based on the overall performance, Nikon’s AF Nikkor 20mm f/2.8 does not quite stack up. The lens shows weak border performance at wide apertures on both full frame as well as APS-C type cameras and falls prone to pretty much all possible artifacts – vignetting, distortion, flare, aperture ghosting, you name it."
I’ve retired and now shoot what my photo colleagues call a "pro-sumer" 35mm DSLR camera. It’s got a little distortion on the wide angle shots. The body and two lenses cost less than the above lens. 😉
And to get the full 20mm lens coverage, you’d need a full frame digital sensor which means you need a Nikon D3, for about $5,000, a D3S or D3X, for about$7,500.