Is there any relation between barrel size and aperture?

[Madmax]

Just a newbie question.

Some lens are 58mm, 62mm, 67mm, etc. Is there any correlation between that and the max aperture size?

 

[Del_CtrlnoAlt]

ya... bigger barrel, bigger aperture... cos more light can passthru.

 

[roti_prata]

1st u hav to understand tt apature no.(f/xx) is a relative concept. its the ratio of lens opening and focal length. so the same sized barrel with same sized opening can mean different apatures at different focal lengths, which is wat u see in most zoom lenses. as it zooms in, the focal length increases but the lens opening stays the same size, so apature no. becomes smaller

 

[+evenstar]

Not all the time..

50mm f1.8 has a barrel size of 52mm? While a 300mm f2.8 has a barrel size of >77mm

 

[doug3fflux]

hmm i think 50/f1 got big barrel?