What Makes Telephoto Lenses Have a Longer Focal Length Than Convex Lenses?

Thread starter copitlory8
Start date Sep 17, 2010
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Convex Difference Focal Lenses

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Telephoto lenses are designed with a longer focal length compared to single convex lenses due to their unique optical construction, which includes multiple lens elements that work together to magnify distant subjects. This design allows telephoto lenses to compress perspective and provide a narrower field of view, making them ideal for capturing distant objects. The longer focal length results in a shallower depth of field, enhancing subject isolation in photography. Additionally, telephoto lenses can achieve greater magnification without increasing the physical size of the lens. Overall, the combination of these features distinguishes telephoto lenses from standard convex lenses.

Sep 17, 2010

copitlory8

Why is a telephoto lens considered to have a longer focal length than that of single convex lens?

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Sep 17, 2010

DaveC426913

Gold Member

copitlory8 said:

Why is a telephoto lens considered to have a longer focal length than that of single convex lens?

The first few sentences http://en.wikipedia.org/wiki/Telephoto_lens" seem to cover that off nicely.

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