Hi, thanks for your help, I'm pretty sure the lens is fine, as its been good for other things. It's the XT-2 body, OIS is on, CH shutter, do you think maxing the ISO to 3200 is too low? I'm concerned about noise... I get the focus lock green square and beep yes. I'm not using zone focus, I am using single point but on the widest setting before it goes to zone. No touchscreen on the XT-2. In terms of eye and focus, I haven't changed these. Do you think I should use zone? My worry with this is, when the horses are running behind a rail, I don't want the camera to shift and lock focus onto that, therefore having some out of focus on the horse. Any info you can help me with is greatly appreciated! Jayne