[Pheo]

So guys,

I'm in a bit of a quandary - I have a big trip planned to America for three weeks and I'm looking at purchasing a new lens...

I'll be visiting San Fran and Arizona.

My two options are (currently)

Replace kit lens with a Tamron f2.8 17-50 - improved IQ in a regular range vs my 18-55 kit lens

Buy a Sigma 10-20mm ultra wide for more creative shots.

Just interested in what you would do?

I shoot on a K10D at the moment. Considering a K30/K5 replacement for creative video later in the year as well...

[luftfluss]

That's a toughie. I always consider focal length first. That is, if I have an OK lens like the 18-55 but feel I need/want wider, I'll get the UWA.

OTOH, not only is the Tamron 17-50 sharper than the 18-55, it's also faster, which may be a consideration if you are intending to shoot indoors or at dusk/nighttime.

[cali92rs]

In my opinion, for the purpose of a vacation, I would go for the Tamron. The Sigma, while I have one and love it, is more specialized.

Edit:
I see you are interested in the Sigma 10-20...I have the 8-16.
The Sigma 10-20 is more useful for a greater variety of shots than the 8-16mm. But i still would go with the Tamron, and save up for the Sigma at a later date. Then at that date, get the 8-16mm to avoid the overlap and get REALLY wide

[VoiceOfReason]

I have the Tamron 17-50, and to tell the truth it gets loads more camera time than my Tamron 10-24, so I'd go for it. It is a very nice general purpose lens.

[calsan]

I would take the kit lens and buy heaps of new glass upon arrival in the USA. There's a lot of whinging about prices going up in the US, but they're still way cheaper than the rest of the planet.

[guinnessman]

When I'm in SF, I basically live off my 10-20...I have the Tamron too, and 10 mm vs 17 mm at the wide end makes a huge difference, especially when surrounded by buildings or taking wide cityscapes.

However, for low light work, the Tamron walks all over it, but that's why I bought the Tamron as well.

[lytrytyr]

Get the Tamron, and stitch if you need wider.

[Pheo]

I would take the kit lens and buy heaps of new glass upon arrival in the USA. There's a lot of whinging about prices going up in the US, but they're still way cheaper than the rest of the planet.

I like this thinking.

However this likely means the Sigma warranty is invalid... seems a concern on an expensive piece of kit (but maybe I'm worrying too much!)

Are any other manufacturers different? I'm not sure.

[SpecialK]

I would likely get the UWA first, unless you are looking for people shots. In that case 50mm may be a bit handier.

[civiletti]

It depends on what you photograph, your style, and what you will likely do with the images. You can answer better than we can.

If you are likely to shoot much at wide aperture, the Tamron is quite superior to the DA kit lens. If you shoot at medium or small aperture, especially if you plan no big enlargements or do extreme cropping, the kit lens will suffice.

I also recommend the Sigma 8-16mm.

[VoiceOfReason]

If you're really set on UWA then I can tell you the Tamron 10-24 is pretty sweet too, and that extra 4mm over the Sigma is nice.

[calsan]

I think we've been thinking about stills a bit much, "creative video" - for that you may wish to consider buying lenses with quick shift manual focus?
So DA12-24?

[Pheo]

I think we've been thinking about stills a bit much, "creative video" - for that you may wish to consider buying lenses with quick shift manual focus?
So DA12-24?

DA12-24 seems pretty expensive... maybe I should consider the extra for the Sigma 10-20 HSM. Although for the amount of time I'll be spending it may not be worth it (this is a hobby, not a job, after all)

[Pheo]

If you're really set on UWA then I can tell you the Tamron 10-24 is pretty sweet too, and that extra 4mm over the Sigma is nice.

The reviews I've seen said it was generally not quite as good as the Sigma, particularly edge sharpness in the examples I saw was very bad... am I missing something?

Maybe I should buy a fisheye!

[northcoastgreg]

The reviews I've seen said it was generally not quite as good as the Sigma, particularly edge sharpness in the examples I saw was very bad... am I missing something?

Were the examples shot wide open or stopped down? Corner to corner sharpness tends to improve when lens are stopped down (to f8). When I was researching the UWA zooms, I don't remember the Sigma being that much better, at least in terms of edge sharpness, to the older Sigma 10-20.

In any case, I would upgrade the kit lens first. Whatever the merits of the DA 18-55, it will be outclassed by any of the UWA zooms you throw against it. So by purchasing an UWA zoom, you'll be getting better images from the lens that covers the less useful focal range.