which wide to hire for Olympic Park architecture?

Same dilemma as me, Sharon, though we didn't get any Olympic tickets

After lots of research and head scratching I had decided on the 8-16mm too, for the same reasons as you - great reviews and (sort of) affordable.

I also considered the hiring route for an upcoming trip to Italy, but thought the hire costs were quite expensive, relative to the lens cost anyway. Also I worried about damaging it!

The 10-17 fisheye is a great lens, too, and something I'd love if I had the money. It's a bit of a specialist lens, though, and whilst the distortion is fun, it's a bit limited for normal use. I'd personally use a standard wide angle more and for a one-off like the Olympics it would be a safer bet.

The 12-24mm looks great, but very expensive and I dismissed it simply on price.

Personally, in your situation, I'd do what I have settled on and get a good used 10-20mm or 8-16mm (but haven't been able to find one of those yet - says something for the lens). A decent used 10-20mm will cost somewhere between £225 and £245 delivered and you won't lose anything if you decide it's not for you and re-sell it. If you rent you will obviously lose the £35 or so that costs plus presumably you need to post it back RMSD.

Having said all that I suspect that you will be so far back in the stadium that your 18-250mm might be perfectly wide enough at 18mm anyway and you have the option of zooming in! I'd take mine if I was going.

Not a comment on lenses but a viewpoint suggestion. A very good view of the Olympic park can be had from the top floor of the John Lewis store in the adjacent Westfield shopping centre. Just go to the Olympic 2012 dept.where there are floor to ceiling windows looking over the site.

For the reasons mylimbar gave, I would go for the renting of the DA12-24.

A fisheye gives a very specific effect and can be very nice in certain shooting situations. The effect however can very quickly get boring in my opinion. They say it's not too fishy at 17mm (or not at all), but in that case you don't gain too much compared to your 18-250. It can be nice to accompany the 18-250 for the occasional shot.

The DA14 is not flexible enough for my liking. I'm not and UWA man and therefore I will prefer something more flexible if I need UWA (like in your situation).

That leaves the DA12-24 from your list. Wider than the DA14 and more flexible.

I agree that the Sigma's are worth a look but you can't rent them so that's not an option.

I'm in a similar dilemma to choose an UWA for architecture purposes. I'm very much doubting between the Sigma 10-20 and the DA12-40. But I'm not in a hurry and probably can wait till the new Pentax 12-35 (or there about; WR?) sees the light and make my decision then.

I have some concerns over the 10-20mm as well, but any lens will have it's fans and detractors. On the whole there are plenty more people who love it than hate it.

I've bought mine from a forum member who has good feedback for selling before and says he has had great images with it. That's probably the way to go secondhand or just buy new from SRS so it can be returned if there is a problem.

That said, I'd definitely stump up the extra £70 to get the 8-16 if I was buying new.

Hopefully mine will arrive before I go to Italy tomorrow. We'll see then how another complete beginner with no experience with a 10-20mm gets on. If nothing else I should be able to report back with some tips on what not to do.......

Having just had and returned an 8-16mm (faulty) I'd agree with milamber. From what I've seen, at average sizes, there's very little between the 8-16mm and the 10-20mm besides the focal length (and the 7 blades on the 8-16mm!).

I think the typical person who buys the 8-16mm either already knows they like wide-angle photography and buy it outright, or are upgrading from the 10-20mm, which is why the 10-20 is more available. Plus the 10-20mm has been available for 5 extra years so a lot more copies are floating around.

Ideally, I'd get a 10-20mm on one camera and put the 18-250mm or 55-300mm on the other camera and then swap around as desired.

If you're not sure if wide angles are for you then you could rent the 12-24mm but I'd think you wouldn't lose any money buying the 10-20mm used and selling it on later.

Might also be worth checking google images for pictures taken of stadiums with the 10-20mm.

If it helps at all this is the field of view I got with a 31mm lens when I went to a test event there 5th May. I took the 31mm because it was a very dull evening and I needed something reasonably fast to get anything at all. A wider lens might have given a more interesting perspective. You can take in cameras and lenses that do not exceed 300mm in length. You will need tickets, either for an event or just for the park, to access the area at all - but I guess you won't be travelling all the way from Devon without having checked this out already

The Sigma 8-16mm has their new FLD glass in it (it stands for 'F Low Dispersion', no really ). This apparently makes it beastly sharp: at 8mm wide open it outresolves the Canon 50D's 15mp sensor in the centre (http://www.photozone.de/canon-eos/515-sigma816f4556apsc?start=1).

I have the 10-20mm, and it's plenty sharp for my liking (it's also my most-used lens). I can see why others might not like it though: the corners at 10mm are weird (don't know whether it's lack of resolution, distortion, or whatever), and it isn't exactly the most petite lens. But let me put it this way: I've grown sufficiently attached to it that it's currently one of my three lens kit, despite my love of Limited primes.

As far as the original topic is concerned, I'd rent the 12-24. I use the 10-20 at its longer end quite a lot (not as much as 10mm though, hence no DA15 yet ), so I imagine the extra reach (of the 12-24 vs the 8-16) at the long end might be quite useful. I definitely wouldn't get the 8-16 (as my only lens) for that reason.