Archived posting to the Leica Users Group, 2011/01/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]It might conceivably still have some use in the digital age. I calculated the DOF for 35mm full-frame with a 50mm f/1.0 lens and the subject at five feet, and it came out to a near limit of 4.91 feet and a far limit of 5.09 feet. I guess there you just go for the eyes and hope they're not too big. That was with a circle of confusion of .03mm. Don't know how these calculations relate to those marked on the lens. For 35mm the COC used is .03mm and I remember it being considerably smaller for LF. This is probably because the 35mm lenses are sharper than the LF lenses. I think. http://www.dofmaster.com/dofjs.html Ken On 1/4/2011 6:24 PM, Mark Rabiner wrote: > For years I thought the CIRCLE OF CONFUSION was an insider joke > photographers played on people trying to learn photography. And that it > really didn't exist at all. Then I tried to place into an advanced photo > class in a community college (color printing) and had to take a placement > test and got in trouble. > > > -------------------- > Mark William Rabiner > Photography > http://gallery.leica-users.org/v/lugalrabs/ > mark at rabinergroup.com > Cars: http://tinyurl.com/2f7ptxb > > > > >> From: Ken Carney<kcarney1 at cox.net> >> Reply-To: Leica Users Group<lug at leica-users.org> >> Date: Tue, 04 Jan 2011 18:12:27 -0600 >> To: Leica Users Group<lug at leica-users.org> >> Subject: Re: [Leica] What are the most important aspects of a photographic >> image ? >> >> I have willed that part out of my mind. I did make a spreadsheet with >> the formulas for front and back focus (Lotus 123 in those days instead >> of Excel). Here are the calculations: >> http://www.dofmaster.com/equations.html >> I like autofocus better. >> >> Ken >> >> On 1/3/2011 8:58 PM, Mark Rabiner wrote: >>> Which circle of confusion did you pick? >>> >>> >>> -------------------- >>> Mark William Rabiner >>> Photography >>> http://gallery.leica-users.org/v/lugalrabs/ >>> mark at rabinergroup.com >>> Cars: http://tinyurl.com/2f7ptxb >>> >>> >>> >>> >>>> From: leo wesson<leowesson at gmail.com> >>>> Reply-To: Leica Users Group<lug at leica-users.org> >>>> Date: Mon, 3 Jan 2011 20:41:38 -0600 >>>> To: Leica Users Group<lug at leica-users.org> >>>> Subject: Re: [Leica] What are the most important aspects of a >>>> photographic >>>> image ? >>>> >>>> Who? >>>> >>>> Thanks! >>>> Leo Wesson >>>> 817.733.9157 >>>> www.leowesson.com >>>> >>>> >>>> On Jan 3, 2011, at 19:30, Ken Carney<kcarney1 at cox.net> wrote: >>>> >>>>> My first photo seminar was with a Famous West Coast Photographer. His >>>>> advice >>>>> was ditch the 35mm and get a real camera (I think I brought an M3 and a >>>>> couple of Summicrons, or maybe a Contax to the class, but definitely >>>>> TriX). >>>>> So I bought a nice 4x5 field outfit, a Linhof Technica and lenses, and >>>>> for >>>>> good measure an 8x10 rig also. The focus part was a little tedious. >>>>> Once >>>>> you knew the distance to the target, you pulled out a little chart for >>>>> each >>>>> lens that showed the range of focus for each stop, based on your >>>>> desired >>>>> circle of confusion. Then you measured the various zones, which gave >>>>> you >>>>> the >>>>> key to the ISO for that shot and thus the development time for that >>>>> particular sheet, based on your densitometer tests. After, of course, >>>>> you >>>>> had consulted your reciprocity failure chart. Sometimes it happened >>>>> that >>>>> by >>>>> the time I made the exposure everything of interest, including the >>>>> light, >>>>> had >>>>> vanished. Then the light bulb began to flicker on that something >>>>> more...immediate...m >>>> ight be appropriate. Then, Gracia Dios, along came digital and the >>>> exposure >>>> comp dial. >>>>> Ken >>>>> >>>>> >>>>> >>>>> On 1/3/2011 6:33 PM, Mark Rabiner wrote: >>>>>> I think its nice to get the thing in focus most the time. >>>>>> >>>>>> >>>>>> -------------------- >>>>>> Mark William Rabiner >>>>>> Photography >>>>>> http://gallery.leica-users.org/v/lugalrabs/ >>>>>> mark at rabinergroup.com >>>>>> Cars: http://tinyurl.com/2f7ptxb >>>>>> >>>>>> >>>>>> >>>>> _______________________________________________ >>>>> Leica Users Group. >>>>> See http://leica-users.org/mailman/listinfo/lug for more information >>>> _______________________________________________ >>>> Leica Users Group. >>>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >