Same Range lenses yet different zoom distances?

Question

why is it that a lens like the Nikkor 70-200mm f/2.8 VR has the ability to zoom farther than say the sigma 70-200,, f/2.8 EX

the 70-200 range is the same...yet the nikkor can zoom farther

why is this?

Answer 1

Can you clarify your question a bit? Such as, what camera you would use those two lenses on?

Really, those two lenses should be able to cover the same distance. 200mm on one lens should be the same as 200mm on another lens. However, some similar lenses may have different perspectives at a given focal length due to manufacturer variation. Thus, an advertised 200mm lens can really have a truer length of say, 195mm. Or another 200mm lens could really be at 205 mm.

Also, the 70-200 f/2.8 VR could have been used on a 1.5x crop camera (such as D80, D60, D300) which gives a perspective of a 105-300mm lens. The Sigma, on the other hand, could have been used on a full frame camera such as the D3 or D700.

Answer 2

As the previous posters said, there should be no difference between the two.

I will emphasize that there will be a difference if someone is shooting on a full frame camera and the other is not. The non-full frame camera will have a 1.6x multiplier and then lens will effectively go to 320mm.

Another possibility is that the other person is using an extender. You can gets tubes and ad-ons that will extend your focal length (usually double it).

Answer 3

Can you give us some examples?

200 mm is 200 mm.  How does the Nikkor zoom out further?