First, welcome to the forums!
Telling us a little about your budget would help greatly.
So would mentioning which lenses you are talking about using. K mount cameras today can use lenses from many decades back to when the mount was introduced, and
there have been quite a few changes along the way.
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K3iii has distinct advantages for shooting older (pre A) lenses, thanks to it's
new metering option for manual aperture lenses. It is, however, also the most expensive K mount camera available and thus not my first thought when it comes to "starting out." Unless dropping a few grand doesn't matter much to you.
K1ii (or the very similar
K1) is full frame, and thus maintains the field of view that the older manual focus lenses were designed for. Again, though, they are more expensive (US$1000+ even for secondhand) cameras than I might recommend to someone "starting out," unless they were specifically looking for full frame. They are actually probably a great choice (even among all camera brands) for someone looking to start out in full frame digital.
The
K70 is available new for a very good value, and if you're skittish about buying secondhand it's the only remotely budget option. It is a very full featured camera, and probably the most obvious "starting" point.
Buying used is also a great way to save even more, particularly if you're okay with older bodies with lower megapixels. The truth is, Pentax DSLRs have been great for a long time now. We know you won't be needing more advanced autofocus, which is one major area where the newest cameras are definitely much better than the older bodies.
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Hope any of that helps, and if you give a little more info about what you're looking for you will get more specific and targeted recommendations. We love helping people buy things!
Last edited by wadge22; 02-03-2022 at 09:45 AM.