09-25-2011, 09:12 AM
If I'm not wrong, the Table-2 in Klaus' link shows 3.7micron pixel pitch limit (for green light) in accordance with f-stop value 11. So starting from ~F/11, the 24mp sensor with that tiny pixels outresolve "the lens" (which lens?... that might be the critical question). And I believe "outresolving" is not the end of the world, as long as one does not see the visual impact on the LCD or the print out. I never saw the famous diffraction effects on images except for the 100% views on the net (and I personally almost never use F/16 and beyond). We cannot deny the impact on the image, but I don't think 100% views alone help with the issue...
OTOH, I believe two points can still be discussed:
1) the Table-2 from LL shows quite a difference for blue and red light wavelengths. Does that somehow prove that the quantified (high) delta in microns does not neccessarily mean that there should be an obvious visual impact, or should we expect different softness based on primary colors?
2) the discussion were around having e.g. a lens with fastest f-stop of F/4 on a 2.7x cropped sensor. The 35mm equivalent value is almost the F/11 border and at first glance this looks like a substantial drawback, because it limits the photographer in terms of DoF control and obviously we're on the diffraction limit. But if I'm not missing something, the 2.7x cropped sensor with F/4 shows the same visual DoF as with the value ~F/11 shows on FF. So with the small format, one does not need to increase the f-number to the lens' diffraction limit to achieve a comparative DoF increase. Coming to the DoF decrease side, if we consider that these small format lenses are smaller in glass size and therefore could possibly have less spherical aberration than their big brothers, it's clear that wide aperture usage should not be a big deal for a decent lens. Of course, in case of a very shallow DoF requirement as in portrait shots, the smaller format has it's limitations obviously (although, I can say that I saw very nice samples from E-P3 + Zuiko 45/1.8 with shallow DoF). Surely 2.7x crop would not be the candidate for portrait but hey, who told that V1 is a good choice for portraits with shallow DoF <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='
' />...
Serkan
OTOH, I believe two points can still be discussed:
1) the Table-2 from LL shows quite a difference for blue and red light wavelengths. Does that somehow prove that the quantified (high) delta in microns does not neccessarily mean that there should be an obvious visual impact, or should we expect different softness based on primary colors?
2) the discussion were around having e.g. a lens with fastest f-stop of F/4 on a 2.7x cropped sensor. The 35mm equivalent value is almost the F/11 border and at first glance this looks like a substantial drawback, because it limits the photographer in terms of DoF control and obviously we're on the diffraction limit. But if I'm not missing something, the 2.7x cropped sensor with F/4 shows the same visual DoF as with the value ~F/11 shows on FF. So with the small format, one does not need to increase the f-number to the lens' diffraction limit to achieve a comparative DoF increase. Coming to the DoF decrease side, if we consider that these small format lenses are smaller in glass size and therefore could possibly have less spherical aberration than their big brothers, it's clear that wide aperture usage should not be a big deal for a decent lens. Of course, in case of a very shallow DoF requirement as in portrait shots, the smaller format has it's limitations obviously (although, I can say that I saw very nice samples from E-P3 + Zuiko 45/1.8 with shallow DoF). Surely 2.7x crop would not be the candidate for portrait but hey, who told that V1 is a good choice for portraits with shallow DoF <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='
' />...Serkan