I have the Tamron version and have previously used a Pentax version of the lens. For info, I think there is no difference in IQ between them (there is some disagreement about whether the Pentax version has difference coatings but I doubt it) and actually the Tamron branded version feels marginally better built (partly because of the different plastics). I would expect the new Sigma to possibly have higher build quality but not sure I'd spend the best part of £500 on such a lens.

The 18-250 covers, as you say, a very impressive range and is a great one size fits most solution or travel lens. At the wider end it largely performs at least as well if not better than the Pentax kit 18-55. At the longer end things fall apart a bit (as you would expect) but the centre always remains acceptably sharp.

Such a lens always involves compromises and with my copy these seem to be:

(1) zoom creep when carrying the camera - you need to use the lock to keep it closed when walking around but you get used to it.

(2) significant barrel distortion at wide angle - but easy to correct in PP.

(3) significant vignetting at wide angle until stopped down to at least f6.3 - again correctable in PP and not such an issue at wide angle given that for most general/landscape use you'd probably stop down to get max sharpness anyway.

(4) problem (3) above gets worse if you stick filters on the front - you have to use expensive thin filters with this lens, not the cheap fat ones.

(5) edge sharpness not good at longer lengths - but may not be such an issue for tele shots if the subject you want to concentrate on is closer to the centre of the frame.

(6) the lens is slow at longer lengths (f6.3) so you need lots of light or high ISOs (in my view this is the single biggest issue).

In conclusion, I think people could do a lot worse than buy this lens to stick on the camera when they want to grab it quickly or travel without a pile of kit. It can then be usefully supplemented with a few choice primes or higher quality zooms once you've decided which aspects of the 18-250 don't quite deliver what you need on occasion. I wouldn't use it for special events, but it's great for general use.

Hope this helps.

Just spoke to SRS and things sounded rather more hopeful than this thread. Sounds like the cameras may already be in this country so I think we are talking days or a week, rather than lots of weeks. I'm sure they'll let us all know as soon as they can!

Hmmm Pentax UK aren't exactly going out of their way to keep their loyal customers. I'm no Ricehigh but this, coupled with excessive price increases for lenses, plus horror stories about competence of their new service partners when things go wrong, is starting to make me question whether - in the UK at least - it is sensible to continue to spend significant sums on a new Pentax body or whether it is better to swap systems to a company that actually appears to value its customers.

If this is the best Pentax UK can do, it's hardly a surprise if dealers aren't terribly keen to do business with them.

If it is the 58mm filter thread SMC K then in good condition it is worth a lot more than £20. Snap it up as long as the aperture blades are working properly and you can't see any fungus when you look through it.

Hi Simon - I use the SMCA 28 f2.8 on occasion and quite like it! Especially as a small and unobtrusive lens for street shots.

It's pretty sharp almost from wide open and on APS-C sensor is almost the perfect standard lens (at 42mm equiv). The downside compared to a real standard lens is that it was originally designed as a wide angle, and it does have some barrel distortion. Not much fringing though (less than on some of my other older primes).

The colours definitely have a look that is similar to some of the other older primes and I feel my pictures with it have a slightly more film/less digital look, although some people don't love the colour from this lens as much as from some of the others.

Mine cost £35 from Ivor Howell in South London, and for that money I'd buy one again. I'd think twice if the price was much more than say £50 though.

PS - enjoying your old Sigma 10-20 - but it's a steep learning curve!

Certainly looks like you're managing to nail focus and depth of field now! On my screeen the shots look a little overexposed - maybe worth dialing in some underexposure as the K10/20 bodies are notorious for overexposing with these old lenses (unless you change the focussing screen). Beware if you get hooked on this lens a whole new hobby of collecting primes is lurking.....

Time to start looking at Sigma and Tamron alternatives - which we can still buy from SRS.

No excuse for blaming them for Pentax price rises - SRS still competitive when you look at some other UK dealers.

Mr Cad not far from where I live and I pop in now and again. It's a great place to look around but unfortunately, not only is their website slow, it's also terribly inaccurate. Whenever I've spotted more interesting stuff on the web, it's usually vapourware when I've got to the shop.

They had a huge load of Pentax stock which I think they bought some time ago when whoever was in charge of the Pentax UK operation changed. The only really rare thing I've seen that remains is the 1000mm lens. Other than that, they have lots of 35mm, 50mm, 200mm and a few zooms. Also some cheap "Chinex" lenses and 35mm bodies (they get the occasional LX for people who are interested). Actually their M42 mount stuff is quite often a lot more interesting.....

Didn't say it wasn't positive - but it missed out so much information about the camera that people who hadn't already read about it elsewhere would have no clue about what differentiates the K-7 from any other dSLR. Almost none of its more interesting features were mentioned (aside from HDR). Even the fact that it is WR, has video mode, is compact, allows recomposition by moving the sensor, at least one of which is a first.

I stand by my original post - if Canon or Nikon had produced a camera with all of these features built in, the article would have mentioned them!

Hi - glad you're enjoying the 135!

Don't know if you have one, but the cheapest fast and great quality Pentax lens out there that'll fit more in is probably the 50mm f1.7. You can find them very easily and cheaply, and you'd pay quite a lot to get something of equal IQ new nowadays. Quite a nice focal length too.

If you want to go wider, I have a 28mm SMC A f2.8 which I like - at 42mm on a dSLR it's a great standard lens for street photography etc. Mine cost £35 incl 6 month warrantee from local secondhand camera shop (Ivor Howell in S London). If you find one at that price or a little more, I'd recommend it.