If a very old flash has ever been attached to this camera, there is a possibility that the camera is at fault and not the flash. Is it possible for you to take both to a Pentax Dealer who would be able to test your camera with another flash, and your flash with another body?

Read the last paragraph on Page 60 of the manual (Referred to on Page 25, referred from Page 27 - Confusing - of course).

When attached to an LX, Super A/Super Program, or 645, the flash display shows P-TTL, but the image is taken using TTL.

Pentax did make a very good hammerhead flash, the AF400T. One went on eBay recently for under £50.00, ridiculously cheap. There's a battery pack to go with it too.

It's also possible to make a good hammerhead flash. You need a hotshoe grip + bracket, either an AF500FTZ or AF540FGZ, hotshoe adapter F and 5P extension cord F. The hotshoe grip needs a modification, you need to drill a hole to isolate the extra pin on the flash. Matt has documented the mod here.

If it's only a fiver, I'd chance it. That same site shows how to dismantle an M42 lens. The M series lenses aren't going to be very different.

The 135-600mm is a super lens. I just wish I had a tripod that could hold it steady. The tripod mount is way to far to the rear making it completely unbalanced & heavy at the front. A Wimberly would fix the problem, at a price.

If you suspect you have a problem, test it, and prove it first. Then decide how much of a problem it is for you before deciding to attempt adjustments.

Sorry Lilly, it's not in the manual. Checkout this topic. Everything you need to know is in there.

You'll need the English version of a Russian programme, some test charts, a USB - K10D cable, and lots of time.

Pentax FA 100mm Macro, Pentax DA* 50-135mm (needed a different offset at the extremes of the zoom range), DA* 16-50mm, DA*300mm, Sigma EX DG 180mm. I can't remember the exact offset figures now, but the Sigma needed around -70um as I recall. The others needed anything between +60um and -20um adjustment.

I now have the K10D set up for the DA* 300mm. I'm just waiting for my K20D to arrive to use the remaining lenses properly.

I decided to do all this because I was unhappy with many of my pics as they were out of focus, not by much, but enough.

I may even get a magnifying eyecup to help with manual focus as well because my tired ol' eyes aren't what they used to be. I'd have bought McBrian's if Matt hadn't beaten me to it.

This focus issue is a problem for me, and evidently for Pentax et al. Why else would they build in the ability to make these per lens adjustments? Answer, because it's needed.

There is an additional problem if you have a collection of Sigma glass. Sigma lenses are not uniquely identified, so the K10D/K20D thinks they are all the same lens. They are simply identified as 'Sigma', nothing else.

You'll need an SD card, K20D can't use C/F.

Chances are, they don't have the pass through contacts, just the 'auto' diaphragm coupling. Seller states that they are "f. Pentax PK".

Kenko tubes are very good.