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Old Feb 16, 2014, 6:09 PM   #11
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Perhaps compare with the Canon "kit" at f/3.5- so they're both wide open...
Though to be fair- Canon's kit lens is one of the better ones optically...in my opinion...
It does seem from these images you've posted that you buy that Tokina lens if you need the 11mm setting- as opposed to the f/2.8....
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Old Feb 20, 2014, 4:56 PM   #12
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I did the infinity fix posted here-
http://www.christianschmeer.com/blog...cus-Adjustment

and I've fixed the f/2.8 focus problem.
That extra bit beyond infinity helped. Now the center sharpness at f/2.8 rivals that of f/8. You can now see the veins in the leaves in the center of the image. The grass in front of the tree has more detail too.

f/2.8 before/after, shot raw, sharpening turned off- http://farm4.staticflickr.com/3833/1...db77c30f_o.jpg

f/2.8 after vs f/8 before- http://farm8.staticflickr.com/7431/1...bf595edf_o.jpg

Now you just have to remember to back up a tiny bit from infinity when shooting at f/8. The fix actually makes f/8 slightly less sharp if turned past infinity.
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Old Feb 20, 2014, 8:54 PM   #13
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You must have a bad lens.
Sorry about the polar vortex, but this is about the only landscape shot (@ f/2.8) found around here today. The CA is definitely there, but this was one of my sharpest lenses when I had the D300:







-> The same Tokina 11-16mm f/2.8 AT-X116 Pro DX on my D800

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Old Feb 20, 2014, 10:13 PM   #14
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do you still have the original unresized image?

my blurry pics look great too when shrunken down to that size.
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Old Feb 21, 2014, 5:21 PM   #15
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I have to look, but this is normally what I use for print:
http://www.pbase.com/nhl/image/154560507
Note I shot this in DX mode (because of the lens) so this is not @ 36Mpx...

-> Why do you really need f/2.8?
Isn't the purpose of this lens is to maximize the DOF to get everything in focus for its perspective distortion?
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Old Feb 21, 2014, 11:04 PM   #16
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Thanks for the bigger image. No need to look for it. That 16mp image will suffice.
My lens is now as sharp as yours after tweaking it.

I don't really need f/2.8 for stills, since I will mostly be using this with a tripod and can compensate with shutter speed.

But for video, I could benefit from f/2.8 for low light indoors, and that's one of the reasons I bought this lens. I would need f/2.8 11mm to be as sharp as possible.

and finally, since I paid for an f/2.8 specifically, I expect it to work, otherwise I would have bought a sigma 10-20 f/4-5.6.
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Old Feb 22, 2014, 3:21 AM   #17
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Quote:
Originally Posted by makeitwide View Post
... since I paid for an f/2.8 specifically, I expect it to work, otherwise I would have bought a sigma 10-20 f/4-5.6.
Where their ranges overlap, the Tokina 11-16/2.8 is sharper and has less vignetting than the Sigma 10-20/4-5.6. The Sigma has less CA, and distortion is about the same.

What you're seeing is that the Tokina isn't as sharp at f/2.8 as it is stopped down, but it's still pretty sharp, and sharper than many other lenses in its class.
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Old Feb 23, 2014, 7:14 AM   #18
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Quote:
Originally Posted by makeitwide View Post
...

But for video, I could benefit from f/2.8 for low light indoors, and that's one of the reasons I bought this lens. I would need f/2.8 11mm to be as sharp as possible.

and finally, since I paid for an f/2.8 specifically, I expect it to work, otherwise I would have bought a sigma 10-20 f/4-5.6.
For video you wouldn't be able to pixel peep on a static image so this won't be a problem (and the camera is not 4k) at all

What you are seeing is a loss of contrast and content dependent also:
o The image appears less sharp in my pictures on the left trees in the shadow area.
o However, the jet streak in the sky, the dirt particles on the snow, or even the right trees on the right all appeared to be sharper.
@ wide open the lens is letting a lot light in and this 'washout' effect is kind of expected. I see this in my f1.4 lens too (and in all my other lens for that matter)!

-> Try turning the video light on and off filming a scene @ f/2.8... The effect is the same as shooting still at f/2.8 with the flash On and Off, the images always appear sharper with better lighting than without
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Old Feb 28, 2014, 12:52 PM   #19
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Makeitwide - a few questions about the fix you applied on the lens:
Did this change where the camera focuses when using autofocus?
Did this make any changes to infinity focus @ f/22?
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Old Feb 28, 2014, 6:51 PM   #20
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Quote:
Originally Posted by rainrunner View Post
Did this change where the camera focuses when using autofocus?
The depth of field for this lens, especially on an APS-C body is such that it would be difficult for an AF system to not get the focus right.

Quote:
Originally Posted by rainrunner View Post
Did this make any changes to infinity focus @ f/22?
The Canon T3i is diffraction limited at about f/14, so f/22 would be pretty bad.
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