18-55 vs 18-140 (focal lengths seem different)

[Philligan]

Hey all, I've got a question about the Nikon 18-55 and 18-140. When they're both set to 18mm, the 18-55 seems wider than the 18-140. Is it because the filter/front element sizes are different?

 

[480sparky]

Not much to worry about. It's very common. Even copies of identical lenses may be different.

 

[Philligan]

Thanks! So they're likely just slightly calibrated differently? I wasn't too worried, more just curious - I wondered if the wider front element changed the field of view.

 

[480sparky]

An 18-55 lens most like will not be exactly 18mm, or 55mm. It may be 17.25-52.17. Or 18.68-56.19.

And focus breathing may affect focal length as well.

 

[TheLost]

Focal lengths listed on lenses are 'more what you'd call "guidelines" than actual rules' (to quote a pirate).