Normal corner sharpness for the Tok 11-16mm?

I'm a little surprised to see extreme corner softness at 11mm F2.8 on my Tokina as I have always heard the lens is sharp corner to corner at F2.8. Perhaps that may have been a slight overstatement. What do you guys think of these examples?

Here are some sample images I took getting use to the FOV of the lens...nothing terrible exciting but shows the soft corners I am talking about:

http://farm6.static.fl​ickr.com …17900273_f79ec1​8f0a_o.jpg (uncorrected CA)
http://farm6.static.fl​ickr.com …18485536_e5b1e9​f089_o.jpg (corrected CA)
http://farm6.static.fl​ickr.com …18486794_090156​3078_o.jpg (slightly different focus point corrected CA)
http://farm6.static.fl​ickr.com …18496690_a888b5​289a_o.jpg (different shot CA corrected F5.6)
http://farm6.static.fl​ickr.com …17918559_70a97b​3576_o.jpg (shot taken exactly perpendicular to wall with some detail in corners...doesn't look too bad but didn't get detail in EXTREME corners)

So...entirely normal amount of CA and soft corners or is there an issue here?

I looked at the photo and checked the exif. You are shooting at f2.8, which is bound to cause distant objects to be OOF.

Try shooting a flat plane or at a smaller aperture.

litlefiter wrote in post #12219920
I looked at the photo and checked the exif. You are shooting at f2.8, which is bound to cause distant objects to be OOF.

Try shooting a flat plane or at a smaller aperture.

I'm not complaining about the DOF. I'm asking about corner sharpness(look at the near corners). I'm just trying to figure out if this is a case of field curvature that I'll need to take into account when focusing F2.8 shots in the future.

They are soft until stopped down to f/5.6-8.
Check mouse over comparison here
http://www.the-digital-picture.com …6-DC-HSM-Lens-Review.aspx

Looks about normal to me for f2.8

But on my monitor the last shot of the framed gas meters it appears the bottom corners are sharper versus the top corners. What do you see ?

Silverfox1 wrote in post #12221065
Looks about normal to me for f2.8

But on my monitor the last shot of the framed gas meters it appears the bottom corners are sharper versus the top corners. What do you see ?

If you are judging that based on the meters themselves, I dont know. I think a lot of that is because of the sun flares on the plastic protectors diffusing some detail. Other than that it looks pretty even. Overall I'm pretty happy with my lens...I just want to make sure there isn't a corner issue.

Andrew_WOT wrote in post #12220673
They are soft until stopped down to f/5.6-8.
Check mouse over comparison here
http://www.the-digital-picture.com …6-DC-HSM-Lens-Review.aspx

Great link and yes mine looks like that but mine also appears sharper just a bit away from the corners. I'm surprised that their copy shows up less sharp than the canon. I thought it was pretty well accepted that the Tok was sharper corner to corner.

Sdiver2489 wrote in post #12221122
Great link and yes mine looks like that but mine also appears sharper just a bit away from the corners. I'm surprised that their copy shows up less sharp than the canon. I thought it was pretty well accepted that the Tok was sharper corner to corner.

This is what I've read on lightrules as well
Some numbers on border performance from lenstip.com
Tokina 11-16

Yeah the only place where my copy is not sharp is the very extreme corners...otherwise I'm quite pleased. I also think this could have to do with field curvature as I mentioned before. I'm going to try manual focusing and move the focus point closer and see if that makes a difference. The focus point in these images was only a few feet in front of me so it may accentuate field curvature. These images sure make it seem like I was far away from the subject though

The other thing to remember is you get some crazy distortion at the edges of UWA lenses that can make things like foilage and branches look soft and "wrong".

It appears to be mostly field curvature. I ran a test and slowly moved through the focus range while taking pictures. A step or two short of infinity focus produced the best result. Once it went to infinity the corners took a bit of a step down. Regardless, except for the extreme corners its sharp...and that's all I expected.