Canon 1D X and 1D C May Have Autofocus Issues… When Shooting Below 0° C


A report on Canon Rumors is pointing out an issue with Canon’s flagship full-frame DSLR and its Cinema counterpart: the 1D X and 1D C. Apparently users have been reporting problems with the 1D X’s AF when shooting in less than 0° C, and if an anonymous report sent to CR is accurate, Canon knows about the problem.

The issue itself seems to revolve around the Locking Claw of the camera’s Sub Mirror (the AF mirror), and although only 1D X cameras have been reported as faulty, the 1D C uses the same mirror box assembly and so it is likely faulty as well.

No official service advisory has been issued but Canon Rumors did receive what looks to be a very official explanation of the problem that might have been distributed within Canon. We won’t go into the details of the problem since you can read the full report here, but there is one particular line that raises concerns.


This is what the text says under the heading “Repair Procedures” (emphasis added):

Handling of units in question: If the user complains about this specific phenomenon (does not autofocus in low temperature), replace the Mirror Box Ass’y with the ones to be shipped in the future (CY3-1661-010 or CY3-1687-010).

Handling of general repairs: If the user does not mention this phenomenon, please handle as normal repair.

CR referred to that last line as “of great concern,” and it does certainly raise some interesting questions. If the user doesn’t bring up the problem because he or she lives in a warm climate, should Canon still not replace the Mirror Assembly if they know it to be faulty? What if that person goes to, say, a workshop or expedition in a very cold climate?

Again, this was sent in by an anonymous source, so we don’t know if it is official, but if it is all of the above questions are valid and the problem should probably be addressed in an official service advisory. What are your thoughts?