I have used loads of lenses with the Ricoh pin on Pentax AF cameras (SFXn & Z-1) without any problems. Most independent manual focus 'KA' lenses also had similar pins (some more rounded than others). I never had a problem getting them off again. When I bought my K-5 I did follow the link above to remove all the Ricoh pins from my lenses (just in case).

I'm a bit late into this thread and have only skimmed the responses. For me it was simple, I went into a shop looking for a micro-four-thirds thingy, and walked out with a K-5. The reason was simple, having been handed a camera I knew nothing about and not having used any DSLR before, it took me less than a minute to become familiar with the 'photography' side of it (exposure/metering/focus modes etc.). Fundamentally it works the same as my Z-1 did. All my old lenses would fit (and work) and so did my flashes, IR remote releases and so on. At the same time all my lenses were upgraded with 'SR' and became half as long again

My M42s are:

Super-Tak 28/3.5 (58mm filter thread)
Optomax 35/2.8
Super-Tak 35/3.5 x2 (f16 & f22 versions)
SMC-Tak 50/1.4
Super-Tak 55/1.8
Super-Tak 55/2
SMC-Tak 135/3.5
Regent 2x TC

I've also got a bunch of Tamron ADII lenses which I could get an M42 mount for.

Thanks Algernon, I'd forgotten about that, which may explain why areas of the print were obviously softer than slide. And there was me blaming my MX & M 28/2.8!

IIRC correctly, if you did sandwich it between two sheets of glass you got Newton's Rings as well.

I agree with much of the above. Contax used a vacuum pressure plate supposedly to minimise film flatness issues. The LX has a longer pressure plate than most Pentax cameras (and longer film guides).

I had a 20x30 inch poster from Kodachrome 25 printed. The detail was amazing but showed up limitations with my gear (MX & M 28/2.8 ) and technique.

If there is a build problem, it is most likely to be in the body, not the lens. The body drives the lens until it has feedback that it is 'in focus' (maximum contrast?) and the only way an 'AF adjustment' would improve things is if the imaging sensor, mirror(s) or AF sensor are out of alignment.

Nah, that's impossible

It's an Osprey VTOL contraption which keeps crashing link, unlike the Fairey Rotodyne which didn't.

I think 35mm is a bit long and somewhere between 21-28 is better, but what constitutes 'street photography' varies. I've been trying a SMC-M 28mm recently and find it just about right, getting an AF one at a reasonable price would be difficult though.

It's not about the gear (or what gear), it has to be good that's a given, but it's more about attitude and aptitude than a bag-ful of expensive lenses. You can do it with three prime lenses (wide-angle, standard & short tele), a decent flash and enough backups/contingency to deal with things failing.

Most of all you have to know what you're doing and be able to deliver the shots in a professional manner. Planning each shoot is at least as important as the gear, as is your workflow from capture to final output.

How wonderful it is to be able to check the image (or histogram) immediately after shooting it, tweak it and have another go if it's wrong. In 'the old days' you often had to wait a week to see how 'correct' your metering had been (probably having forgotten how you did it in the first place).

To answer the OP, you need to use it when the camera meter is fooled by the subject brightness. This is difficult when using matrix/evaluative/segmented metering as these may (or may not) have already compensated for the problem. Thus it only really works in spot or (less precisely) center-weighted metering.

When dealing with tricky lighting I do check the histogram etc. but I always prefer to use manual mode than auto with exp. comp.

Thanks pepe,

Yes it works fine on the AD2 PKA.

John.