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Lens
Suppose that you wish to flatter Cyrano. You'll want to back up until you are separated by the length of
a football field. Now his nose is still 5" closer to the camera but that is 5" out of 100 yards (note for
European readers: 100 yards is just short of half a standard furlong.) So instead of being 50% of the
distance to the camera as Cyrano's eyes, the nose is 99.86% of the distance away. It will not be
significantly more prominent.
What about the 24mm lens from this camera position? It will give you a nice photo of the entire stadium
and the city behind it. Cyrano's face will appear as a portion of a grain of silver on the film. You're now
100 yards away from Cyrano so you will need the Mother of All Telephoto Lenses. In fact, according to
the formulas in my Kodak Professional Photoguide, if Cyrano's face is 12" high, you will need a
7500mm lens to fill the frame with it. Cyrano will be flattered but considering that a Canon 600mm lens
costs almost $10,000, the effect on your wallet will not be a happy one.
Exactly how long a lens do you need?
How far away is your subject? (in feet)
How high is the object you want to fill the frame? (in
feet)
Apologies to people from countries that have adopted sensible units.
If film and lenses were perfect... you would need only one lens!
In a perfect world, I'd walk about with only my Canon 14 super-wide lens. I'd worry only about my
camera position, secure in the knowledge that the 14mm lens was wide enough to capture my entire
subject under 99% of conditions. Then if I wanted a picture for my Web site of just my friend in the
middle of the frame, I'd crop down to just the center and use that. The result would be the same as if I'd
used a 100mm portrait lens.
http://www.photo.net/making-photographs/lens (2 of 9)7/3/2005 2:22:04 AM