On 8 Jun 2004 at 11:30, Boris Liberman wrote: > Hi! > > It would appear from the most recent talk that Sharpness is more or > less __the__ most important characteristic of the lens. However, from > previous talks it has become my understanding that Pentax do not > optimize their lenses specially for sharpness (except may be macro > lenses and such). Pentax, AFAIU, optimize their lenses for plasticity, > or overall smoothness of the picture. > > OTOH, Nikon are known for having their lenses tack sharp all over the > frame. At least this is what I have accumulated in my small knowledge > bag so far.
Hi Boris, I'm not sure if I'm about to confuse you or not but I suspect that these theories that you mention are really only relevant to older prime lenses and film use. Virtually all late primes are sharp enough as to be sharper than the sensors can resolve at all but their extreme aperture and some are even good at the extremes. The biggest problems regarding lens compatibility on DSLRs is mainly chromatic aberration. Zooms are another story, many particularly the older ones are quite poor. The links that Dario recently put up show these differences very graphically. > Please unconfuse me - why all this talk about sharpness? I do realize > that for digital lenses should be very sharp. Or at least, it would be > a reasonable thing - to want one's lenses to be sharp. But sharpness > is not all, right? Part of the recent talk of sharpness was referring to in-camera sharpening, this is an independent issue to lens sharpness. The talk of the F series zoom sharpness was another story. I had the SMC F 70-210 f4.0-5.6 and I'm sorry to report that it was quite poor in all respects relative to my primes. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
