Do Telephoto Lenses Produce Different-Looking Pictures than Standard-Design Lenses in the Same Focal Length?greenspun.com : LUSENET : Large format photography : One Thread
At the risk of appearing stupid or annoying again in my elementary questions about lenses, I would like to pose another one about telephoto vs normal-design lenses. With all issues regarding bellows-draw aside, do telephoto-design large-format lenses produce pictures that look in any way diferent than standard-design large-format lenses, in the same focal length, aperature, focus-distance etc? I am concerned primarily with compression of space--and the extent to which each MIGHT differ in the degree and manner of spatial compression it produces, particularly with respect to the possible differences in depth-of-field between the two lens types, at the same focal lenth, distance-of-focus, and f-stop. Does the telephoto lens produce greater compression--or more "dramatic pictures" if you will--perhaps owing to an inherently shallower depth of field than the normal-design lens, in the same focal length, etc--or would the two pictures be indistinguishable in their "look"-- apart, of course, from the obvious expected differences between manufacturers and lens lines within the same manufacture?
-- Nick Rowan (firstname.lastname@example.org), March 04, 2000
-- Chris Patti (email@example.com), March 05, 2000.
Nick, contrary to popular belief, there is no compression at all from any length lens, only cropping. If you look at a scene with the naked eye, the area which will be photographed with the long lens looks no different to the lens than it does to your eye. It just gets cropped. check it out sometime.
-- mark lindsey (firstname.lastname@example.org), March 05, 2000.
Nick: The results would be the same if subject-camera distance is the same. There is a design difference between say a standard design 300mm and a telephoto 300mm, but the magnification of the image is the same. The telephoto design moves the nodal point forward to allow shorter bellows extension. If you are using front movements, the standard design is a hell of a lot easier to use due to the axis of the movements being near the center of the lens with axis swing and tilt movement standards on the camera. The compression, or telephoto "look" is due to distance from the subject. As the previous respondent said, if you make a negative from the same spot with a 90mm and 300 mm lens and print and crop the 90mm picture to exactly fit the one made with the 300mm, the pictures should be identical. Hope this helps, Doug
-- Doug Paramore (email@example.com), March 05, 2000.
FWIW, I didn't find my Fujo 400T telephoto lens significantly more difficult to use with front movements than a normal lens. I had read about this telephoto lens "problem" before buying the lens and was concerned about it but it didn't prove to be any problem. On a few occasions I maybe had to go through one more iteration of "focus on the near - tilt - refocus on the near" than normal but this was rare and even when it did occur it added maybe five seconds to the time it took to make the photograph. Maybe the Fufi telephoto lenses are just designed better than others or something but I didn't notice any significant difference between using the telephoto lens and using a "normal" lens.
-- Brian Ellis (firstname.lastname@example.org), March 05, 2000.
Just a short comment about Mark Lindsey's statement. I agree that cropping affects the "compression". If you cropped the centre out of a negative shot with a 90 mm lens, the compression effect would be identical to the full framed shot with a 300 mm lens.
Now having said that, it can also be stated: Using all of the negative will affect the apparent compression. This is important in that there is a practical difference in compression from wide angle neg to long focal length/telephoto lens, since most photographers will use all of the negative.
Perhaps I'm being silly but I think that Mr. Lindsey's statement could easily be misunderstood.
-- David Grandy (email@example.com), March 05, 2000.
Nick, if perspective remains unaffected whatever the lens, I wonder if the following is not what you are looking for: The separating power. This is not often considered in large format photography, but in wildlife photography, a good telephoto lens is one with a good separating power (A Nikkor f2.8-300 as compared to a f4.0 for example).This means it can separate a sharp plan of focus from a blurred background thanks to good sharpness at large openings. Most of the time, large format lenses are considered for their resolving power only which require closing the lens to f11-f16 or more, resulting in space compression. Some luminous large format lenses have been specially designed to produce high resolution at wide openings. They usually open at f5.6 with focals of 250-300 for 4x5". New, these lenses are huge and rather expensive (Tele-Arton should be an example, or perhaps the older Rotelar from Rodenstock if I am not wrong) and produce images that are "softly modeled" and sharp at the same time (I hope my french to english translation makes sense!)
-- Paul Schilliger (firstname.lastname@example.org), March 06, 2000.
I just want to thank all of those who have so far replied with an answer to my question--both on and off site--I am just so impressed and gratified by the generosity and degree of knowledge of everyone who takes part in this large format discussion; I have learned SO much from reading through all the many many questions and answers within this forum! I will TRY to respond individually over the the next day or two to those who took the time to reply! Thanks again!
-- Nick Rowan (email@example.com), March 06, 2000.