I have a 70-200 f/4L non-IS lens that has been acting strangely. I've owned it for 3 years, but over the past few weeks, it's been hunting (and not finding) focus when pointed at distant objects while zoomed in. If I point at closer objects (10-20 feet), it's fine. Or if I zoom further out, it's fine for distance.
When it hunts, it's very rapid in a narrow range near infinity. Almost like a chattering effect. Again, if I zoom out, it settles down.
It's not the camera, as I've tried the lens on my 5D3 and 60D. The problem exists on both. My other lenses are fine.
It's worth noting that it only happens when I'm viewing through the eyepiece. It seems to work normally in live-view.
Any thoughts would be appreciated.
Thanks!
Jay
