The F-number of a photographic lens is a measure of its light-gathering ability, and is expressed as its aperture diameter ...

We flew to Aizu, Japanm to find out how some of the world’s best and most popular lenses are made at Sigma's one and only ...

Welcome to Nat Geo Your Shot: National Geographic’s global community for aspiring visual storytellers. Find the community on Instagram @NatGeoYourShot and follow along for hashtag challenges ...