Tuesday, October 16, 2007

Truth and Telephoto lenses




Ah, the dreaded Wide Angle Telephoto lens!!! How did I manage to forget that one? I recall many a cold winter evening, gathered about the pot bellied stove in the photo lab, the lively philosophical discussions as we delved into the mysteries of light and photography... images and editors. Truth and telephoto lenses. Who would not long for the day....

As I recall, it was Al Sund who stirred the congregation up over the Truth in Telephoto issue. The position that most of us took, picture editors included was: “the longer the lens, the more compression of the image.” Thus the editorial objection to Windle’s street scene taken with a telephoto lens and where all the signs and power poles looked as if they were so close they were rubbing together. The photo editor determined the telephoto lens had rendered Truth altered and the photo would not be appropriate to run. Al’s position remained that it was not the lens at all, but simply the position of the camera in relation to the subject. Further, it was not distorting the truth, but representing it exactly as it appeared. That is, Al contended, if you are a given distance from a given subject, the “ distance compression” will be exactly the same, regardless of the focal length of the lens you use to view it. He even went so far as to say that it would actually look the same to your eyes without any additional lens. The reaction was immediate and passionate... mine included.... “Friend Sund, thou speakest heresy I say, HERESY! Everyone knows it is the lens that compresses the apparent distance between objects! How about looking through binoculars? Huh? The lenses compress everything together. Any fool can see that.” At least we were right about the ‘fool’ part.

As a converted disciple of Al Sund, I went out and took these photos today. They are taken with a 28mm wide angle and a 210mm, mild telephoto from the same position. Yep, the compression and distortion in the telephoto is obvious. The train cars are in reality about 60 feet long and about 8 feet high, say an 8:1 ratio and they look like that... close to the camera... in the 28 mm photo. In the telephoto picture, the distant cars appear to be (quoting Pogo) squeened down and squeened together so that now they look shorter than they are tall, a less than 1:1 ratio. The billboards, which are really alongside the freeway, look like they overhang the train cars. And check out the impossible curve of the road. Yup, it is all distorted. And that nasty distortion, obviously because of that darned old telephoto lens, is what the photo editor objected to .

In the search for truth, I now offer the third picture... which is actually just a cropped and enlarged section of the 28mm photo. As you can see, when the objects are the same size in the photo, and still same distance from the lens, whether the wide angle or telephoto , they are virtually identical! Brothers and Sisters, we have found the elusive Wide Angle Telephoto!

Well, ok, the resolution, clarity, detail are obviously much worse in the 28mm pic when it is enlarged... soooo, does that make the wide angle shot the worse offender in the Truth Altered category? I can tell you that is how they appeared to my eyes but I wear glasses, so maybe I can't see what is truth?

At least, Al Sund was right about telephoto lenses.

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