I would appreciate an explanation or a referral to where my question might be answered. Often older large format lenses are described in terms of inches instead of a millimeter clasification. For example, an article may refer to a 5" lens instead of stating the mm designation that we use now.

Can anyone tell me how you can tell the focal length of a lens that is referred to in inches. thanks

-- john zimbelman (zman@magiclink.com), September 12, 1998

Answers

Multiply the inches by 25.4.

-- Tim Brown (brownt@ase.com), September 12, 1998.