If you’re the owner of either a Canon EOS-1D X or -1D C digital camera, you may have noticed some technical difficulties with your camera’s autofocus mode. Some users have discovered that the autofocus systems in both cameras may not work properly – if at all – in cold weather conditions. And despite it being a known issue, users may be the one to foot the bill to rectify this problem, since Canon has not issued a recall or acknowledged the issue.

According to Canon Rumors, the AF system of these full-frame DSLRs do not work in temperatures below 0. Supposedly, the system will neither autofocus nor utilize any of the camera’s AF points to lock onto your subject. Both models are pro-level cameras, so the majority of Canon’s consumer DSLR users aren’t affected.

Canon has yet to officially comment on the cause of this serious hardware issue, but an anonymous source told Canon Rumors that “this phenomenon is due to the Locking Claw of the Sub Mirror (mirror for AF) going over the Locking Pin. The Sub Mirror’s angle becomes deviated and the light rays for AF does not fall on the AF sensors, causing the ‘does not autofocus’ phenomenon.” (Check out Canon Rumors for an illustration of the problem.)

And because Canon hasn’t issued a service advisory, the same source alleges that Canon is charging customers up to $450 to repair the autofocus issues on camera bodies and lenses, if they’re out of warranty.

Canon may have already corrected the autofocusing flaw on later models, Canon Rumors says; if you purchased either of these cameras after January 24 of this year, no need to worry. For those of you with an earlier model, there’s a strong possibility that you’ll end up spending more money to correct this problem – a problem that’s no fault of the user. This brings to mind the issue affecting Nikon’s D600; that camera’s problem is unrelated, but Nikon took too long to respond to users’ complaints, prompting several class-action lawsuits in the U.S. and a ban of its sale in China. Nikon has since issued a service advisory. Let’s hope Canon doesn’t take too long to address these concerns.

(Via Canon Rumors)