Hi Bob, As I understood it (but I may be wrong):
* With A-lenses and A-bodies in A-mode, the body only pushes the lens lever the right amount to reach the right aperture, and that's why the lever's operation must be linear. * With pre-A bodies and/or pre-A lenses, the body actuator always pushes the lens lever all the way through, which results in the lens closing to the aperture preset on the ring. So it doesn't make any difference whether the lever effect is linear or not, in this case. This might explain why you could never see any difference. Regards Patrice Bob Sullivan a écrit : > [...] > > In practice, I've wondered about it, but never been able to notice any > difference in the slides my cameras produced with "A" vs K or M > lenses. I always attributed any differenced to the light transmission > qualities of the lens itself. > > Regards, Bob S. > > On 3/26/07, Igor Roshchin <[EMAIL PROTECTED]> wrote: > >> Hello! >> >> Sorry for bringing up this question that may be known to most >> of the people here. I just realized that I don't know it, and couldn't >> find the information on the KMP site or elsewhere on the web. >> >> This question is about aperture control design. >> For the A and later lenses that have "A" setting on the aperture ring, - >> what is the step of the actual aperture setting in this mode? >> If it doesn't coinside with F-stops or 1/2-F-stops, then is it >> body-dependent (i.e. is one body more capable to utilize >> sub-1/2-f-stops then another) or is it standardized? >> >> I realize that the motion of the diaphragm actuator in the lens is >> stepless, so it is up to the body to choose the steps, if any >> (is it determined by the DAC bitness?) >> >> Thank you, >> >> Igor >> >> >> >> >> -- >> PDML Pentax-Discuss Mail List >> PDML@pdml.net >> http://pdml.net/mailman/listinfo/pdml_pdml.net >> >> > > -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
