lens closer

[kareem]

Pls inform me how I know the lens 300mm for example closer the target or objective.Are there any table for that?
B.RGDS

[cyracles]

Hello Kareem, could you please rephrase the question. I do not understand.

[kareem]

If any person asked me the lens 300mm for example,how much this lens enlarge the target?

[dubaiphil]

Depends how big you print the image!


Sounds like confusion between multipliers when attributed to point and shoot zoom lenses and mm when talking about DSLR/Medium Format.

e.g. - a 24mm-70mm lens offers virtually 3x zoom

[barry3]

If any person asked me the lens 300mm for example,how much this lens enlarge the target?

As I understand it the human eye is equivalent to 50mm,so 300mm is 6x.

[Hero]

Kareem, this link might help you unstand the difference between focal lengths: http://tamron-usa.com/lenses/learnin...comparison.php

[Dave Humphries]

Hi Kareem,

Or are you asking about the closest focus distance between subject (target) and lens front element (objective)?

Welcome to the CiC forums from ...

[William W]

The question appears to me to be about a target being enlarged by a telephoto lens (i.e. as seen in the viewfinder) with respect the view of a ‘standard lens’, for a particular camera’s format.

For the computation: you divide the Focal Length of the telephoto lens by the Focal Length ‘standard lens’ for the camera’s format.

i.e.

A 300mm lens on a 135 format camera (aka “full frame”) such as a Canon 5D, will enlarge the target about 6 times. The ‘standard lens’ is (about) 50mm
300/50 = 6

A 300mm lens on an APS-C format camera such as a Canon 50D will enlarge the target about 10 times. The ‘standard lens’ is (about) 30mm
300/30 = 10

WW