> On Sep 15, 2019, at 5:42 PM, P. J. Alling <webstertwenty...@gmail.com> wrote: > > You also have to take into account viewing distance, and the resolution of > the viewing device. The higher the resolution of the viewing device the more > accurate you assessment of DOF will be when printed.
I’m not so interested in absolute depth of field as the shape of the way the level of focus changes with distance. To get the absolute DoF you’d take a slice at the final effective resolution. Based on Bruce’s comments, I suspect that a larger format ends up being at a different point on the curve. > > On 9/15/2019 3:23 PM, Larry Colen wrote: >> Bruce Walker commented on facebook about how with medium format you get a >> particular transition from in focus to out of focus which finally made >> something click for me. Everybody talks about depth of field as if it is a >> sharp transition, but it isn't, and the same image could have different >> depths of field at different sizes and resolutions. How many photos look >> just fine as thumbnails/contact prints, but are out of focus, or mis-focused >> at a larger size/higher resolution? What I would love to see are graphs of >> the size of the circle of confusion, preferably a 3-d graph that would show >> it based both on focal length and distance. you could also show a slice at a >> particular pixel size which would give you the nominal depth of field. Does >> anyone know of someone having done graphs, or better yet a program where you >> can enter those values and see them change for yourself? >> >> >> -- >> Larry Colen >> l...@red4est.com >> >> >> >> > -- > America wasn't founded so that we could all be better. > America was founded so we could all be anything we damn well please. > - P.J. O'Rourke > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- Larry Colen l...@red4est.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
