I the past few weeks my Canon 70-200 F2.8L felt somewhat strange then it became more and more obvious that is sick. The lens elements became loose. The front element above the focus ring and in the middle, just below the focus ring. The general feel was that the lens is going to fall apart and break in two. Not a happy tune.
Watched a YouTube video about it, the only one how to fix it and I wasn’t very happy to see what’s waiting for me. Not an ideal thing to to in the back of the van in a campground in Ecuador. But deep breath, lined up some tools, cleared some space and got on it. After I pulled off the mounting ring it became obvious in a second that the lens in the video, an IS is different than mine, non-IS. So I was on my own, but still the video was a good guideline(ish).
Not an ideal place and situation to pull apart a Canon L lens, but then again I need this glass quite often. Pulled apart the whole focusing thing, pulled out four micro conduit connections then got down to the space where I needed to tighten the screws. It’s a very clear situation, no way around it, you can tighten these screws only by pulling the lens apart.
You need to tighten those five black screws. Once done with that I just assembled everything back in reverse order. Everything is tiny, the space is tight, fun fun fun. Put the lens on the &D2, nada. AF warning was flashing in the viewfinder. Huffed and puffed and pulled the lens apart again. Good thing I took photos with a full frame camera as I was pulling it apart as it saved me lots of search and nerves. It turned out that it was one of those tiny flat electric connections assembled the wrong way. Looks like it was possible.
You see those letters on the conduit just below the black adhesive tape? That was the answer. When I inspected the conduits the writing was upside down. All the other connections were straight forward beside this one. You need to twist the conduit, only this one, when connecting it back. Made no sense at first assembly. Threw back all the parts again, (sounds easier than it is) mounted the lens and voila, auto AF was doing its job again. Breathing became normal again after this moment.
Off we went to test the whole thing with, who else, Blaze.