Canon published a product advisory acknowledging the existence of a 'light leak' issue on the EOS 5D Mark III. Users of the camera have reported that in dark conditions, switching on the top-LCD's back-illumination or shining a light on it alters the 5D Mark III's metering, suggesting a 'light leak' inside the camera body that is reaching the metering sensor. The company says it is investigating the problem and possible countermeasures and will make further announcements once a decisions has been made on resolving the issue. Petapixel.com reported on the issue and has linked to user videos which illustrate the problem.
To Users of the Canon EOS 5D Mark III Digital SLR Camera
Thank you for using Canon products.
The phenomenon described below has been confirmed when using the Canon EOS 5D Mark III Digital SLR Camera.
Canon is now examining the countermeasures and once the countermeasures are decided, we will post the information on our Web site.
In extremely dark environments, if the LCD panel illuminates, the displayed exposure value may change as a result of the AE sensor’s detection of light from the LCD panel.
Canon EOS 5D Mark III Digital SLR Camera
Once the preparations are complete, we will be making an announcement on our Web site.
This information is for residents of the United States and Puerto Rico only. If you do not reside in the USA or Puerto Rico, please contact the Canon Customer Support Center in your region.
Please register the EOS 5D Mark III. By registering, we will be able to notify you via email when service updates are available. If you already registered, please ensure you are opted-in to receive the notification.
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