Archived posting to the Leica Users Group, 1999/07/09
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 7:43 pm +0200 9/7/99, Jim Brick wrote: >Every lens, except some zooms and I think the Tri-Elmar, has DOF info, for >that lens, engraved on the lens itself. The instruction booklet or most >photo texts also tell how to read this engraved scale. Aberrations aren't >involved. Lenses of the same focal length and at the same f/stop, at the >same distance, have the same DOF. > >Jim > I have been causing misunderstanding.;-) What I wanted to suggest is that out-of-focus image or bokeh quite near the plane of focus varies from lens to lens. For example, I feel a shallower DOF with 35/2 asph than with 35/2 non asph at wider f/stops, most probably because image sharpness with the asph is higher in the place of focus and declines more steeply with distance from the plane of focus. Such differenece can occur among lenses with an identical DOF which is theoretically calculated rather than measured. I wish my English were better.... Cheers, Mikiro