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Old Jul 17, 2009, 1:27 PM   #11
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Also, for sharpness f5.6 up through 18mm and f8 through the rest of the range is the sweet spot. dpreview has a nice tool that is very usable for this. Also, this is essentially the same lens as the Tokina 12-24...

.[/QUOTE]

Hey IO,
Are you saying the Tokina 12-24 is the same lense as the Pentax?
I could have saved $220 if I'd have known that!

Oh well, Live and learn as they say...
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Old Jul 17, 2009, 1:27 PM   #12
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Originally Posted by Keltech View Post
PTlens is a good program for dealing with distortion. You can download a free trial version and see how it works with your lens.

Lou
In addition to Lou's suggestion above, CS & PSE also have a very versatile perspective correction tool as well as "correct camera distortion" tfilter that works very well.
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Old Jul 17, 2009, 1:44 PM   #13
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I'll be very interested to find out how this lens works out. I'm trying to decide if I want to go for the Pentax/Tokina 12-24mm f/4 lens or the Tokina 11-16 f/2.8 lens.
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Old Jul 17, 2009, 1:44 PM   #14
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It is a common misconception, but what you are seeing exemplified by the last picture technically is not distortion - it is a matter of perspective (convergence of otherwise parallel lines into the distance which is not necessarily undesirable), and there are ways of correcting it in pp. (defishing, etc). Holding the camera level and cropping off unwanted space is the best way to minimize it. Lines bowing outwards from the center or inward towards the center are true distortions (barrel and pincushion distortions) - barrel distortion is most frequent at the wide end and pincushion at the long end of zooms. A wide angle lens that is free of pronounced barrel distortion (as opposed to a fisheye) is considered rectilinear and is the most desirable one to have. Hope this helps.

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Old Jul 17, 2009, 1:57 PM   #15
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I've been waiting all week for you to say you got it. Cool!

I don't know anything about these lenses, but wouldn't the flag pole (and palm tree) be straighter if you shot from a lower vantage point? Don't ask me how that relates to the other images seeming to be "straight".

Anyway, the images look very sharp and clear. Is that your bike in the first one?

Patty

Hey Patty,
Yeah, like Harriet said. It makes things worse the more out of parallel you are to the subject, the more distortion you see. I don't think this will be a big problem because as others have mentioned, you can correct it fairly easily with PP.

Yes, that's my bike. It was kind of a strange feeling parking there yesterday, I use to park there all the time years ago when I lived upstairs. I'll share that story with you another time.
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Old Jul 17, 2009, 2:05 PM   #16
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I would say that this lens performs very well regarding distortion when related to a lot of others I've seen.

Glad you got your new toy and welcome to the world of wwwiiidddeeee!!
Thank you Mark.
and a strange new world it is too!
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Old Jul 17, 2009, 2:14 PM   #17
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Originally Posted by Biro View Post
I'll be very interested to find out how this lens works out. I'm trying to decide if I want to go for the Pentax/Tokina 12-24mm f/4 lens or the Tokina 11-16 f/2.8 lens.
Unless I am mistaken the Tokina 11-16 f/2.8 is only available in Nikon and Canon mounts. I also think that the Tokina 12-24 and the Pentax 12-24 share a common heritage (similar to the Tokina and Pentax 50-135).
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Old Jul 17, 2009, 2:16 PM   #18
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Very nice shots you know this is my next lens, don't mind me asking but how much you pay for it as i am in the States now and thinking of buying it here

Hey Hercules,
I don't mind a bit, I got this one from B&H Photo for $719 but, if this is actually same as the Tokina 12-24mm f/4 AT-X 124AF Pro DX II, then you can get that one for $499
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Old Jul 17, 2009, 2:22 PM   #19
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Me definitely wants one of them lenses!

So... what's stopping you?
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Old Jul 17, 2009, 2:26 PM   #20
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It is a common misconception, but what you are seeing exemplified by the last picture technically is not distortion - it is a matter of perspective (convergence of otherwise parallel lines into the distance which is not necessarily undesirable), and there are ways of correcting it in pp. (defishing, etc). Holding the camera level and cropping off unwanted space is the best way to minimize it. Lines bowing outwards from the center or inward towards the center are true distortions (barrel and pincushion distortions) - barrel distortion is most frequent at the wide end and pincushion at the long end of zooms. A wide angle lens that is free of pronounced barrel distortion (as opposed to a fisheye) is considered rectilinear and is the most desirable one to have. Hope this helps.
Thanks Pen, its so easy to get the terminology messed up.
Glad you got us straitened out.
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