View Single Post
Old 23rd November 2018
Loup Garou's Avatar
Loup Garou Loup Garou is offline
Full member
Join Date: May 2012
Location: Royal Wootton Bassett
Posts: 723
Thanks: 98
Thanked 44 Times in 44 Posts
Likes: 51
Liked 65 Times in 52 Posts
Lenses: relative length & diameter

I am no expert in the physics involved in lens-making but always thought that with same-fit lenses having the same max apertures, the lens with a longer focal length would be longer and larger than the other one. If that is the case, how is it that the Sigma 56mm f1.4 DC DN is significantly shorter than the Sigma 30mm f1.4 DC DN (which I own and do NOT think is too big like some people do)?
Reply With Quote