Does your Canon 17-85mm IS lens give an err99 on the camera? Does the problem come and go, seemingly at random?
Most often, this situation is caused by a bad aperture control unit inside the lens, and LeZot Camera Repair can help. Canon cameras are programmed to display err99 for a large number of problems, though, so we need to determine if the fault is in the camera, or the lens.
First, a little test:
- Set the camera to Av mode (aperture priority)
- Select the widest aperture possible (f/4.5 or 5.6) - the camera should fire with no errors
- Now change to a tighter aperture, such as f/22 - if the camera gives an error at f/22, but not at f/4.5, that's a bad aperture unit.
Still in Av mode, with aperture set to f/22, look into the lens while depressing the depth-of-field preview button - you should be able to see the aperture "winking" at you as you press and release the button. If nothing changes, then the aperture isn't working.
Here at LeZot, we have replaced the power diaphragm in many Canon 17-85mm f4.5-5.6 IS lenses, and we can repair yours too! The total cost for this service is $125.00, which includes all parts, labor, and return shipping!
If you have any questions, or would like help with the test procedure, give us a call at 800-286-9027 or 802-863-6989 ext. 3.