Eric Pederson
7-Feb-2002, 19:42
I'm shooting a lot of close-ups with very 3 dimensional objects on 4x5 film with a Schneider Symmar-S 150mm lens extended out to nearing 1:1 reproduction. At le ast printing on 16x20" paper (4-5x enlargment) the resolution is looking a bit v ague. I'm assuming that much of this is from the diffraction which comes from a typical *effective* aperture in the neighborhood of f64 or even f90. Of course, this lens is not optimized for close up work, but I wonder whether or not such a lens would really offer appreciably higher resolution at such apertures anyway.
In my comparing lenses for 35mm equipment and at effective apertures around f16 -22, the macros (not just "close focussing consumer lenses", but lenses like the Zuiko 80mm macro lens on bellows) clearly have higher resolution than normal le nses with lots of extension. But I'm curious whether this would hold for LF lens es stopped way down. In other words, is macro optical design irrelevant and diff raction limited, or is the nature of close-focusing distortion with standard len ses distinguishable from diffraction? I'm unlikely to use an LF lens at less tha n effective f32 for most subjects. (I don't have an optimized-for-close-focusing LF lens to run my own tests.)
In my comparing lenses for 35mm equipment and at effective apertures around f16 -22, the macros (not just "close focussing consumer lenses", but lenses like the Zuiko 80mm macro lens on bellows) clearly have higher resolution than normal le nses with lots of extension. But I'm curious whether this would hold for LF lens es stopped way down. In other words, is macro optical design irrelevant and diff raction limited, or is the nature of close-focusing distortion with standard len ses distinguishable from diffraction? I'm unlikely to use an LF lens at less tha n effective f32 for most subjects. (I don't have an optimized-for-close-focusing LF lens to run my own tests.)