Bob H , Sep 05, 2010; 02:24 p.m.
To start, I have saved my Pentax lenses that have been unused for too long. I shot Pentax from the screw era through SMCP A manual focus and skipped the auto focus cameras and lenses in favor of the original Pentax 645 that still functions flawlessly. My four favorites were the SMCP M 28/2.8, the SMCP M 50/1.2, the SMC 85/2.2 Soft Focus, and the 70-210 SMCP A. When I bought my first DSLR I looked at the K20D, and ended up buying the Nikon D5000, a camera that made me very happy until my son had it with him more than I did. This morning, I went to breakfast with a friend who brought his K7 along with many images from a recent trip to Hong Kong. I liked the images that he made and the feel of the K7 enough to consider getting one, especially to be able to use my favorite lenses listed above again. My question would be, will I be able to switch between my older Pentax lenses and the newer DA lenses without having to make a lot of setting adjustments? Thanks in advance for your comments.
John Shriver 
, Sep 05, 2010; 03:39 p.m.
All of the Pentax DLSR's have the "crippled" KAF2 mount, that lacks the lever to read what aperture the lens is set at. So you have to use stop-down metering for anything older than Pentax-A lenses.
There's one setup menu item to let you use the pre-A lenses ("allow aperture ring" or something like that), which you can always leave enabled. To meter the pre-A lenses, you use a button to do stop-down metering. The stop-down metering may not always be completely accurate, but you can always check the histogram (it's an option in "chimp" mode).
That said, the Pentax-A 28/2.8 is really quite common and cheap used. Same for all the Pentax-A 50mm leneses, save the 50/1.2. Of course, you would really only want to use the Pentax-M 50/1.2 wide open, so stop-down metering isn't really a liability.
Don't forget that the K7 sensor is APS-C size, so you have a 1.5X crop factor.
Michael Elenko , Sep 05, 2010; 03:55 p.m.
Bob,
John's description is accurate. Those "M" lenses are pretty easy to use on a Pentax DSLR. I tend to use the auto-bracketing function with "M" lenses more frequently because the exposures can be less predictable. With 8-16g memory cards affordable, why not?
If you go this way, which I would encourage, I would love to see shots taken with your Soft Focus 85mm. That one's on the rare side.
ME
Nick Siebers , Sep 05, 2010; 10:13 p.m.
The A lenses basically work just as they did on film bodies. As John and Michael said, M and K lenses require stop down metering. It is still pretty easy to use those, though. And the K7 seems like a great camera - if you could get good results form your Nikon, I am sure you could make a K7 work for you.
Peter Barnes 
, Sep 05, 2010; 10:27 p.m.
"will I be able to switch between my older Pentax lenses and the newer DA lenses without having to make a lot of
setting adjustments?" Yes. For M and K series lenses you will need to make a one time setting to allow the use of an
aperture ring, A series you don't even have to do that.
Justin Serpico 
, Sep 06, 2010; 12:28 p.m.
What everyone said above is accurate.
I think you'll love the K-7, I miss mine so much (off for repair) that I didn't even take a DSLR with me on vacation. I ended up taking a 120 film camera and a digital compact. I think it is well known how ground breaking I felt the K10D was, and how good the IQ still is, but the K-7 is a totally different class of camera, and of course the IQ is exceptional.
I definitely prefer "A" or newer lenses on the DSLRs from Pentax, but using older lenses isn't too much of a chore. I have a 55mm I.8 I occasionally use, and a 28mm f/2 Kiron I use as well. Of course the DA Limited lineup is so nice (build and optics) that it's hard not to recommend these as an upgrade over time.
Justin Serpico , Sep 06, 2010; 12:28 p.m.
What everyone said above is accurate.
I think you'll love the K-7, I miss mine so much (off for repair) that I didn't even take a DSLR with me on vacation. I ended up taking a 120 film camera and a digital compact. I think it is well known how ground breaking I felt the K10D was, and how good the IQ still is, but the K-7 is a totally different class of camera, and of course the IQ is exceptional.
I definitely prefer "A" or newer lenses on the DSLRs from Pentax, but using older lenses isn't too much of a chore. I have a 55mm I.8 I occasionally use, and a 28mm f/2 Kiron I use as well. Of course the DA Limited lineup is so nice (build and optics) that it's hard not to recommend these as an upgrade over time.
