I know the K-m flash sync speed is 1/180, so I usually set it to that (manually), set the aperture to what the flash expects, then use the Auto mode on the flash to set the exposure. No trouble so far. Mind you, it also seems to work fine if I use an old Pentax AF240Z with both camera and flash set to "P" - it generally shoots at around 1/45 and f8 or so depending on ISO setting.

Who else has snow then? Been out playing in it, although I didn't feel inclined to risk the K-m and new 35mm f2.4 with large fluffy snowflakes coming down at a fair rate, so I've shot a couple of slides on the KX and will hopefully take more before long!

I'm really annoyed that I never got to shoot any Kodachrome now, it has an even better "retro" look than the Boots colour slide I buy now (got a few rolls in store and one on the go at the moment).

Weirdly my Grandmother recently sorted her old wardrobe out and came up with a small box of slide photos taken in the late 1950s on Kodachrome. The colours are as good as if they'd been taken yesterday!

I've also been digging some up from Dad's slide collection (runs from his buying a K2 in the late '70s through to the last time he took it on a family holiday in the mid 1990s), unfortunately some of those have gone mouldy. I managed to clean some of it off with a dampened cotton bud but I think it'll be a scanner/GIMP job to recover them fully. That said, I might just try projecting them and photographing them with the K-m as I'm guessing I'll get better results that way...

If that doesn't work try a Giottos "Rocket Blower" and then if all else fails the Arctic Butterfly. The Butterfly is apparently superb but at the price they charge it really should be!

I'll settle for a 135mm f2.8 as good as the new 35mm f2.4 for about the £200 mark personally, there are plenty of expensive lenses out there already for those who can afford them!

It does sound as though the zoom mechanism might have jumped off its runners, although I haven't fiddled with any modern lenses (just too complex for DIY repair). I bought an old Tokina 28mm a while ago with jammed focusing which turned out to have been dropped at some point - after persuading it back into the (plastic) thread and resetting the infinity stop it seems ok, although it sounded terrible!

One other thing to bear in mind: You can fit M42 (screw mount) lenses to your K20D but you need an adapter, the best one is the genuine Pentax (as it's quite tricky to machine the bayonet fitting properly and 3rd party ones often don't fit too well) but this can be quite expensive. Worth factoring into your costs! It can also be fiddly to remove. If you want a specific Takumar then most of these lenses were redeveloped for the K mount with the original SMC Pentax range of 1975-77. I leave the Takumars on the Spotmatic/SV and buy the K series for my later film and digital bodies.

Are all the Zeiss-badged 135mm lenses Sonnars? I've been keeping an eye open for a cheap one as I fancy having a go with this different lens design and I now have a reliable Spotmatic to use M42 lenses on. The K-m seems to have major problems with the adapter and underexposes horribly no matter what you try.

You might also be able to clear it using the "sensor clean" function assuming your camera has one. This vibrates the sensor to shake dust off and usually works pretty well.

I suspect it's to do with portraits. A 50mm lens on crop sensor digital isn't far off the field of view of the classic 85mm portrait lens on 35mm film, and the fast aperture allows you a lot of control over depth of field. Don't get me wrong, I have a few 50mm (and a rather nice SMC Pentax 55mm) but they stay on the film cameras as I don't tend to do portraits. I much prefer wild rugged countryside with as few people as possible!

I was browsing a manual focus lens forum recently while looking for sample images from an Auto-Takumar 55mm f2 (just after bagging one on ebay) and came across a comment that while many manufacturers had offered 135mm lenses there were at the same time almost no stinkers out there. The M 135mm f3.5 is a cracker though and not too expensive - you could buy that lens with its known capability to produce superb results or two or three cheapies of uncertain quality.