I believe digital lenses is Sigma marketing wording made up for certain lenses (particularly wide angles) designed to project parallel rays of light on the focus plane. Apparently the industry is close to overcome this restriction with sensors less sensitive to incident angle of light ray. And anyway, the Sigma initiative was not particularly successful so the term flopped.
There's nothing wrong with old lenses on a digital body. Some exquisite primes will work just great, many others will fail with chromatic aberrations and heavy light fall-off. It'll be a natural selection, there's no need for manufacturer's intervention to preclude use of this or that lens. Besides, I doubt the early A lenses, or for that matter even some recent FA lenses were build with digital requirements in mind. It is Pentax's job to release lenses with better performance and - why not? - bearing new technologies like IS, USM, to convince the customer to buy new lenses. Servus, Alin Pål wrote: PJ> In other words, lens quality is far more critical with eg. the PJ> *ist D than with a Pentax 35mm slr. This could also be a factor PJ> behind why Pentax would limit 20+ year old lenses on the *ist D. PJ> Perhaps they aren't realy suited for a DSLR?
