Will a Sigma 28-300 DL (not the newer DG ) hyperzoom work on digital camera namely my Pentax K100d ?

any idea's ? The lens in question was used on a FIlm camera can it be used on a digital

The original camera was a Pentax MZ 30... I cant find much information on that camera..

If anybody can tell me if a lens for this camera would be a K-mount that would be great..

If it is a K-mount lens, yes. Knowing what film camera you used it on would be helpful.

if it`s the same `fitting` yes it will work ,you may have to focus manually.

Pentax kept the faith with it's buying public by keepig the K mount from the film media, and added the necessary electronics so that anyone using film camera lenses could use them on the digital cameras, albeit in manual focus mode, and vive versa with digital lenses.
I bought one of the lenses you mention for use on an ME Super, because the just weren't many available 2nd hand Pentax lenses in the shops. In short, yes, it will work, but to what degree I'm not sure, other than the fact that you will obtain a magnification of around 1.5 x the lenses rating, thus 28 to 300 will become 42 to 450mm focal length (or thereabouts).
The fact that it was used on a film camera shouldn't affect it's operation, since the contacts would not have touched anything in the lens throat.
Incidentally, I have still to sell mine, complete in mint condition and in original packaging.

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