05-19-2012, 10:39 AM
[quote name='AAC7man' timestamp='1337418561' post='18299']
Just to throw another ingredient into the soup, 'older' lens designs seem worse for PF, in addition to the other factors such as wide aperture.
An example is the Nikkor 180mm F/2.8.
So you could argue that yes, telecentricity is a factor in PF. However, the example I quote here is a tele lens, and a redesign would be unlikely to make incident light rays much more perpendicular to the sensor.[/quote]
I would think specific internal reflections, which are more and more eliminated by stopping down, aid and abet to this effect. Maybe the 180 has more of these flaws than another lens. I am thinking coating, and possibly reflections of metal parts in the lens.
I would expect, everything else staying the same, that removal of AA-filters, making AA-filters thinner, and using the best possible coatings on AA-filters would diminish the effect. I expect the Leica M-Monochrom to show very little PF... <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />
Kind regards, Wim
Just to throw another ingredient into the soup, 'older' lens designs seem worse for PF, in addition to the other factors such as wide aperture.
An example is the Nikkor 180mm F/2.8.
So you could argue that yes, telecentricity is a factor in PF. However, the example I quote here is a tele lens, and a redesign would be unlikely to make incident light rays much more perpendicular to the sensor.[/quote]
I would think specific internal reflections, which are more and more eliminated by stopping down, aid and abet to this effect. Maybe the 180 has more of these flaws than another lens. I am thinking coating, and possibly reflections of metal parts in the lens.
Quote:And yes, before anybody says it, some modern designs show the effect too. For example Nikkor 35mm F/1.8 DX
Regarding the effect of sensor, has anyone seen an improving trend with newly-introduced sensors? I'm still back in the dark ages with D40/D200.
I would expect, everything else staying the same, that removal of AA-filters, making AA-filters thinner, and using the best possible coatings on AA-filters would diminish the effect. I expect the Leica M-Monochrom to show very little PF... <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....