Earlier today, I decided to upgrade the firmware on my D610, from I think 1.01, something like that, to 1.04. Everything goes smoothly, so I try my fav lens, Sigma 50-500mm 4-6.3 APO DG HSM EX. It is not auto focusing now, last night and earlier, it worked fine. I think that I was experimenting with something I read, back button focus (bbf), and I think I may have left it on that, which I think was the dial for manual focus/auto focus. I did the two green button reset, which I think should have deleted the bbf info, but I am not sure. I keep it on aperture priority for the most part, and also tried auto, neither worked. I am pretty sure this lens is one that does not work on the 3000 or 5000 series, but should work on the D610. I tried the lens on a D90 and D100, and it was okay. I also tried an AF-S 18-55 kit lens and it worked on the camera. I took the lens to a local reputable camera store a few days ago for a firmware upgrade and they said that as far as they could tell, it wasn't upgrade able, and I know it is an older lens. If it is the firmware, does anyone have older versions that I could get? I would really appreciate it, or if there is operator error, let's get it corrected! Thank you!
Rob
Rob