You've got a D70. I would strongly urge you to investigate the Nikon 12-24mm f/4G ED-IF AF-S more (yes, its a $950 lens).

That said, [link] is a good read.

When comparing lenses for a digital body I strongly reccomend going to a store that has all the lenses in question and shoot a frame with each wide open. Then examine the corners and edges of the frames closely to see which one has the sharpness you are willing to accept at a price you are willing to accept.

Additionaly, feel the lens and how it focuses and zooms.

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Michael (shagie)

I actually played with the 10-20mm today. Very slick, though the zoom and focus rings are a bit stiff. They don't carry the Tokina (and Tamron is a special order) here, so my choice is a no-brainer.
I've read (specifically on dpreview.com) that the sigma lens outperforms the tokina.

I'm debating on picking the lens up before my trip tomorrow (its currently on hold, and seems to be the only one available in the city). I won't be able to get my opinions up until September though

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We had a dream, we had everything. We rode to the end of the world

That's what I really wanted! To touch and feel the lens myself... but sadly I live in a place where there aren't many stores who actually have the lens... About the sharpness of both lenses I've read good and bad reviews of the two, so. One question I have though is if the diference between 12 and 10mm is really important...

The Nikon lens is absolutely out of question. I'ts my father's money so... tight budget.

I do not believe that the diffrence between 10 and 12mm is that signficant when it comes to composition. It is a few degrees - I don't have the exact numbers but you're looking at about 4-8 degrees on a frame that is already about 100 degrees.

Aside from that, not too much I can say when comparing the Tokina and Sigma lenses.

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Michael (shagie)

the tokina has been rated sharper than the nikon. I use the tokina on my d2x.

[link]
[link]

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Save The Alien Legal Fund

the difference is that he can spend 150 bucks not 900 :S you went far off of the priceline of both lenses

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WoW they came with a sneaky surprise attack at the start of the round!

The diffrence between the wide end of the Tokina 12-24 and the Sigma 10-20 is a few degrees on about a 100 degree field of view. That is not signficant.

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Michael (shagie)

LOL i am talking about the 150 lenses and 900 hundred lens that is a hughe difference talking about budget

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WoW they came with a sneaky surprise attack at the start of the round!

`shagie has a tendency to ignore monetary reality when it comes to pursuing optical perfection.

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Edmonton's 1^st DevMeet! August 27!

and where exactly do you see a 150 bucks ultra-wideangle zoom?
the cheapest one in the link above is 500
and getting a lifetime lens from the start is cheaper than getting one that you will grow out after some years or even months and then having to get a better lens
(i speak from experience (canon 28-135mm))