I was taking some pictures at my sister's bridal shower today and started to notice that the wall a foot behind her was more in focus than her face. I took a few more pictures and started to get worried about the lens. However, when I switched to AI Servo mode, the lens seems to focus just fine. When I got home, I put on a 50mm 1.8 and both modes seem to be focusing fine in some tests I conducted.
Does it make sense that the lens would only back focus in One Shot mode and not AI Servo mode? I'm a little concerned but at least the lens is still usable if I only shoot in AI Servo mode, which I have been doing a lot more of lately. However, whenever I give my camera to someone else to shoot, having the camera beep is important, which it only does in One Shot mode.
Any advice? I've had this lens for about 5 years and have never had any issues with it. I have a Canon T2i with the Magic Lantern software on it. The lens was also working last weekend, so something changed in the last week.
