Focal Length Question

Started Feb 8, 2013 | Discussions thread
arachnophilia
Senior MemberPosts: 2,959Gear list
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Re: Focal Length Question
In reply to epijay, Feb 8, 2013

Hope some wise person/optic Physicist will weigh in. The Camera lenses we use are composite "lenses"; however, I am having a hard time reconciling the numbers: A 600mm lens (the Nikkor for eg) is reported to be 19 inches in length (outside dimensions). Without measuring the thickness of the flanges and mount etc, 19 inches translates to 482.6 mm. I would have thought a 600 mm lens would at the very least be 60 cms in length (from Objective to image plane)= 23 inches. Anybody have any opinions on this?

"In photography and cinematography, a telephoto lens is a specific type of a long-focus lens in which the physical length of the lens is shorter than the focal length"

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Nikon D700 Nikon D300S Nikon AF-S Nikkor 70-200mm f/2.8G ED VR Nikon AF-S Nikkor 24-70mm f/2.8G ED Nikon AF Nikkor 50mm f/1.4D
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