You might try Photome. It is free.

There is a lot of myth and lore about this "reverse engineering" theory.

Each lens has an identifier string which is a series of "1"s and "0"s stored electronically. This has to be interpreted by the software which looks up the string up in a library. If it is not there, then one of two results will occur - it will either report the lens as unknown or the wrong one.

A well known example of this was the version of Photome available a year ago, which used to report the Sigma 150-500 as a 70-210 (IIRC). This was updated and correctly identified the 150-500 even on older photos. This proves that the problem was with Photome.

It maybe that Pentax require payment to include other manufacturers' lenses in the library in their software and Sigma have refused to pay them, but that does not constitute reverse engineering.

May 2010 bring everyone what they want.

Fisrt camera was a box Brownie which IIRC used 620 film given to me in the late sixties. First 35mm was my OM1 which I got in the mid eighties and then the K20 which I got last year.

Magnesium powder?

Er - sorry

I wonder where you would stand with warranty claims.

For the first few they are similar, but with the class 2 they taper off earlier.

Just tried a quick experiment with my K20. Set to raw+jpeg with the Sandisc extreme III class six, I can take 10-11 pictures on fast multiple exposure before the buffer fills up and it grinds to a standstill.

With a class 2 card it manages 6-7.

QED.

Some of their prices look interesting -

DA* 50-135, $819.

DA 16-45, $599

Thanks for the replies Gents. By the sound of it, it must have a moving lens.