So, not long ago I bought my first Sigma lens: Sigma 50mm f/1.4 ART. At first I thought it's working fine and I credited occasional AF misses to my incompetence. Human error is quite common when it comes to fast lenses. But then I read on the internet about inconsistent AF with Sigma lenses and it got me thinking. I set up my tripod and did some test shots. I found out it's front focusing on close distances, evens out at about 1.5m and then starts to back focus. I experimented with AF microadjustment in my Canon 6D and these are my approx. values needed for various distances: 40cm: +17 60cm: +14 100cm: +4 150cm: 0 400cm: -10 As the offset isn't constant, I need to adjust the lens based on various distances. I thought of few options: 1. RMA (though I heard it's not 100% and can come back with different issues) 2. Sigma USB Dock (is it effective enough to justify the purchase??) 3. sell the lens and buy one from a different manufacturer (Canon/Tamron?) Can you advise me what would you do based on these findings? Are the values too off to be fixed easily? I'm not really comfortable with sending my camera away just to get one lens fixed, so I'm not sure about the first option. Also focusing in live view is without any issues and the lens is REALLY sharp when it nails the focus. Of course, every other lens is working perfectly fine.