I have always done as Mark does. For example, a filter that sells for £50 comes up, the seller is reliable and says it is as brand new with postage of £3.

The most I'd pay is £35 quid, less postage, my maximum bid therefore is £32. I put that bid in anytime since if someone else bids more I'll lose it anyway but also if the highest last minute bid is £28.50, I'll get it for £29.

I just bid to buy. My wife, however enjoys the bidding, eBay or proper auction and that's how people get to pay too much sometimes.

Incidentally, I've sold two Pentax lenses on eBay and in both cases got more than I paid for them because it was just after the period when Pentax went silly with their prices.

Mine is a self portrait in Johanessburg on a job. I liked the hats the cool black guys were wearing there so bought one and a pair of the round sunglasses they were wearing at the time.

Then I had a few hours free and used the the company Mac with Photoshop (v1, as I recall!) to mess around a bit. I ended up with a blue tone duotone which is and isn't me, as it were. I liked that so avatar it became.

I have found a few people interested in whether they iPad woulkd be of any interest to a photographer so I've put a short demo here (iPad and K5)

The 60-250mm is a great zoom, less good at the 60mm end but still OK.

I just bought a 200mm f2.8, too and that is outstanding. Nonetheless, you'd have to look at results side by side to see the difference. And a gem to use, too.

The only problem - not fault - with the 60-250 is its bulk and weight but until someone changes the laws of optics, I guess there is little that can be done about that.

I've always imagined an Elvis lookalike competition where Elvis joins the line-up and is very annoyed when he doesn't win.

I have a Garmin eTrex (about £60) so before a shoot in multiple locations I make sure the K5 and eTrex times are in sync - they always are. Then, when I get back, I open the eTrex track in Google Earth and I can see the exact locations I was in at the time the picture was taken.

The thing is about the eTrex that it has so many more uses than a dedicated GPS camera unit and is a quarter the price. One of the best uses - if you go to the NEC or O2 or a strange town, just Mark where your car is parked. Never lose your car again!

The right hand one looks a teeny bit sharper to me but for practical purposes, I wouldn't see any difference.

I also think I can detect a tiny bit of barrel distortion in the right hand one so I'll take that as the kit zoom.

If I'm right, please send my £500 prize to my home address. If I'm wrong, I 'll have another go

I remember when I tested the 18-55 against my 15mm and found the zoom was sharper. I was well ****ed off.

You'd need a crop at 100% to really judge and the lens wide open.

Worth a punt, though. Either you get a bargain or you have paid around the normal price with a little inconvenience added.

I'd wondered whether it was a camera/ lens combination fault or just the lens. From your experience, it's just the lens.

Sigma can put it right I'd think. I know they can the 50mm. They should maybe sort out their QC, too.