Archived posting to the Leica Users Group, 2003/04/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Thursday, April 24, 2003, at 02:54 PM, Austin Franklin wrote: > Henning, > >> DOF is dependent on focal length and aperture value >> alone, and only slightly modified by the different circle of >> confusion criteria for different formats. > > Good grief, Hemming. The DOF is HIGHLY dependant on the COC. The COC > significantly modifies the DOF for the same focal length, aperture, and > distance. To be precise: DOF = [sH/(H+s)] - [sH/(H-s)] = where H = f^2/Nc H = hyperfocal distance f = lens focal length s = focus distance N = f-number c = circle of confusion A quick expansion of the equation shows that for DOF varies roughly inversely with CoC. - -- John Brownlow http://www.pinkheadedbug.com http://www.unintended-consequences.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html