I've done quite a bit of reading on the 18-250 and the general consensus is that it's a good lens,just one question: Do the lens correction options available in the K-5 work with both versions or is this only useable on the Pentax branded lens?

IQ is quite important to me, as I like nice colours and contrast as well as decent sharpness, I'd ideally like to move forward with a lens that focuses more quietly that the 4.5 year old Sigma 18-200 DC that I've used with my GX-10, that really does have a noisy focusing mechanism and makes me conscious of shooting in some situations. How noisy is the 18-250 when it comes to focusing?

I've done crops and have got some nice images from them. The thing that annoys me about the 18-270 is the price, it's a rebranded Tamron, that in Canikon mounts is £349 at my local Wilkinson's store, but effectively the same lens branded as Pentax in PKAF mount at £599 is extracting the Michael a bit. I like to buy from my local dealer because of the after sales aspect as it's close to my place of work and is handy for me.

A lot's the need for a a bit more reach without having to change lenses, which can be a nuisance when photographing buses in particular, the 18-55 whilst good is a tad short in a quite a few locations.

Oh my word Alan, those are quality shots. The contrast, and colour reproduction are what I'm getting from my existing DA lenses!

Thanks Bob, I wouldn't buy the 18-270, as for me, it's too much in one barrel, I've been there and done that in my film days with a Tokina 35-300 that ended up falling apart on me and was beyond economic repair. I haven't had the chance to try an 18-135 yet, but will be looking to do so before I make my decision on what to buy.

I was amazed by the macro capability of the Sigma, the whole feel of it completely blew away the old Sigma 18-200 I've had as a walkaround for the last four and a half years. The guy I was talking to has the Sigma on his Eos and says it's tack sharp and reproduces colours very well. I've seen shots taken on the 18-135 on the other Pentax Forum of railway subjects and was very impressed as I primarily do transport photography.

I'm looking to upgrade my 18-55 WR to something with better image quality and a better focal length range and have thought of the following:

Pentax DA 17-70 f4
Pentax DA 18-135 WR f3.5-5.6
Sigma DC 17-70 DC f2.8-4 Macro C

I've had demonstrations of the two 17-70s and liked the Pentax on the K5, please could fellow Pentaxians offer any input into which is considered best?

You beat me to it Daz! It doesn't have quick-shift.

Agreed John. The now notorious German test of the DA 18-135 being a case in point of this, so many people have commented on how good that lens is. My own real world experience of the DA 50 is that it's a cracking lens with lots of contrast and the colour reproduction which we all like about Pentax lenses.

Has anyone had any dealings with this company? I ask as they're listed as a Pro Dealer on the Ricoh website and was wondering what they're like to deal with.