I met someone that was visiting from France a while ago when I was photographing at the botanical gardens. It looked like she was upset and was having trouble taking photos. I guess she noticed that I had a camera similar to hers so she and her traveling companions came up to me. In heavy accents and broken English, they asked me if I knew anything about their camera that wasn’t behaving. I took a careful look at it, to kind of trouble shoot for her, and tried to snap off some shots with different settings. After a few minutes of messing with the camera, it was clear; the error on the back LCD screen wasn’t going to clear. At one point I even got it to take a picture, but it was very dark and underexposed. The lens seemed to dilate just fine however, and I tried the lens on my camera and worked just fine. Long story short… It needed serious repair.
This is a great video done by the techs at C.R.I.S. Camera Services. When the aperture control on a DLSR stops working it is a real pain to fix, but these they make it look easy. Basically, what happened are the mechanisms that control the aperture, in the camera body, have been seriously disturbed somehow. This can happen when the lens is not properly attached to the camera or a lens that is not compatible is attempted to be attached to the camera. Other possibilities include, dropping it or shocking it in some way that doesn’t seem to hurt anything but later manifests as problems like these. After speaking with the young lady (in the above story) a bit though, it was pretty clear that it was damaged in transit by way of her plane carry on. My best guess is that it was caused by some serious stress to where the lens and body couple; which wore on the machinery just right.