The DA50 is a sharp lens. Should be amazing, really. At f3.5, you should be stunned at the sharpness. Have you adjusted the focus for FF/BF?
Fixing Front and Back Focus - Introduction - In-Depth Reviews
Looking at your picture, I'm guessing front focus. Try dialing in -5 and shoot again. Also, I think when you upload to PF, the resolution is much smaller than the original, which highlights the blurriness.
Here's my attempt at making it a bit better. exposure +25, contrast +6, highlights -5, shadows +5, whites +6, blacks -15, clarity +17, temp +13, tint +14, green saturation -31, aqua -21. I also upped the sharpening a bit. That looks like it added some artifacts, but should work better from the original.