Do I have a "defective" Tokina 11-16 F2.8?

[ahson]

I got myself a Tokina 11-16 F2.8 for my Canon T1i not too long ago. I used the lens a lot to shoot and I find my pictures aren't as 'sharp' as every other Tokina 11-16 users had mentioned. Also I find my pictures taken by this lens has serious noise issue. Is this normal for this lens?

I've uploaded a test picture for your reference


Please advise



F5.6/11mm/ISO100/No Correction at all. Straight from RAW to JPG