There are people on here with experience of the 17-70s you are looking at. I have heard in a few places of the Pentax version having focusing issues around the 50mm mark. If it were me given that option then I'd go for the Sigma which also has a great reputation for it's IQ.

The 17-70 seems to me to be the best zoom you can get that meets your needs. Most high quality zooms are x2 or x3 so at x4, and still highly thought of (both the Pentax & the Sigma) is something.

Well done Ted for capturing the beginning of the Mersey tidal bore ..... what ? What do you mean the Mersey doesn't have a bore ?!?

Nice job Ted. Panos of this size aren't easy. Which lens did you use ? The full size version looks impressive - so many changes since I worked in the Custom House (just to the right of the Liver Building). The Liverpool Echo has a new home too.

The Mersey is pretty wide at this point (was this shot from Eastham Ferry ?) and maybe a short tele next time (and ensuring each shot is taken without any vertical movement - which may have caused the 'bore') would give you a better FoV ? Just a thought.

Yes I find it useful as I contemplate upgrading my current ball-head. Thanks for this Philip. Excellent.

This isn't a new issue and it's not an issue that relates only to Pentax, I am on enough non-camera specific forums to note that it is an issue that DSLRs in general seem to have problems over-coming in low light. At least the consumer/prosumer cameras, probably the people using the top of the range CaNikon cameras already know how to over-come this issue.

You can set a global adjustment (and switch it off later) or lens specific adjustment if you spend a lot of time shooting in one particular environment, as it seems you do. If you do a lot of wide-open shooting then you should already know that MF can't be beaten and therefore this particular focusing issue is not therefore an issue at all. I love low DoF and now have two 1.2 lenses to go with the few 1.4 I have .... I rarely use AF for these except when shooting in environments I have no control over.

That's like saying I drive like a nutter but have never had an accident ...... oh !

Often one never knows in these situations what caused the issue, was it something one did or a problem inherent in the lens ? Fact you got it sorted for 100 is pretty damn good though.

Merry Xmas everyone !

250-600mm. Someone switch the lights off please

Not quite sure what you want here . ... a telephoto zoom, a telephoto non-zoom, or a macro lens ?

If money is tight then the Tamron 70-300 is a very decent zoom for very little dosh (around £80 - 100 ?) and although the 55-300 is definitely a better lens, the Tamron wins hands down when it comes to macro as it does a very decent 1:2 that is no gimmick and will give you lovely flower shots etc. .. the Pentax doesn't do macro full stop.

Otherwise if you are looking for a telephoto macro lens then the best value for money by far is the Tamron 90 Di Macro which does a superb 1:1 and is also a very good telephoto for portraits, street etc.

Ha ha - well I hope this one lives up to my hype otherwise I'm going to be very red-faced - I'm sure it will

The Sigma is one lens that is always in my bag (no matter which bag it is, work, play or events). 43mm most times too.

That's a brilliant lens Philip - you're going to love it !

Pity Matt has to sell up because that was a really nice kit.

Swings and roundabouts because if you edit panoramas or anything in 16:9 then you are losing out. Also if you watch films etc. on a 4:3 then again it just doesn't look right.