Archived posting to the Leica Users Group, 2002/08/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]right, but if you'll read carefully (notice the uppercase letters in the subject line), you'll see that i was claiming to have made up the term "HYPOfocal," not "HYPERfocal." and i was joking. my question was based upon the fact that we generally think of and discuss hyperfocal distance with regard to infinity. i was wondering how to calculate depth of field SHORTER than the shortest focusing distance on my lens. best, brad On Wednesday, November 27, 2002, at 06:02 PM, Dave Richards wrote: > Sorry to burst your bubble, Brad, but hyperfocal focusing has been > around as long > as there have been focusable lenses and depth of field scales. > > My copy of the Leica Manual, edition 12, 1951, had a handy dandy > algorithm for > calculating depth of field. It uses parameters such as circle of > confusion, which > really isn't as confusing as it sounds, and effective diameter of the > lens. If you can > find a copy of this manual, probably any edition, look in the chapter > on lenses. You > will also find an algorithm for calculation hyperfocal distance. This > is a handy book > for anyone interested in the technical aspect of the equipment, > Leicaphiles or > otherwise. > > Dave Richards > >> okay, i understand how hyperfocal distance works--in fact, i used it >> today while walking around scaring the bezeesus out of people on the >> streets of chicago by unexpectedly taking their pictures--but what >> about >> hypofocal (???)[1] distance? for instance, say i stop my lens down all >> the way, then focus it all the way to the *closest* focusing distance. >> i know i have some depth of field *closer* than the plane of focus, but >> i don't know how much. >> >> is there a formula for calculating this? >> >> [1] i'm totally aware that "hypofocal distance" is probably something i >> just made up. if so, i get the neologism of the day award. and for >> once, a new word and/or phrase i created isn't dirty. momma's gonna be >> so proud. > > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html > > - -- brad daly bwdaly@bigfatpipe.net http://www.bigfatpipe.net/~bwdaly http://www.bigfatpipe.net/~bwdaly/paw.html "There's no way drugs can effect music in a negative way." --Brian Wilson "I pledge allegiance to Queen Frag and her mighty state of hysteria." --Calvin and Hobbes "War, what is it good for? It's good for business." --Billy Bragg - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html