When you pay more than four grand for a digital camera, you expect it to work right. That's apparently not the case with the EOS 1D Mark III, touted at its introduction by Canon as the "most advanced DSLR ever produced."

In a letter purportedly sent to dealers in the United Kingdom and posted on a forum for Canon enthusiasts, the company stated:

"We would like to make you aware that we have concluded that there is a quality issue with some EOS-1D Mark III units in the market. The problem can be linked to the adjustment of the AF Sub Mirror, and we believe that this affects only a minority of units in the market at this time.

"The phenomenon resulting from this problem (especially in high temperature) is that the optimal focus point is uncertain in AI servo mode, or that the tracking performance of AI Servo is not accurate.

"Regarding the products that have been sold to consumers, we are currently preparing a resolution for this issue and will inform you of further detailed information and required steps through our official website at the end of October or the beginning of November. Canon will accept these units for repair, but we will not be offering an exchange or return.

"In order to ensure that the customer experience is not damaged, and as a responsible company, Canon has decided to stop the shipment of all EOS-1D Mark III. We would therefore like to collect all unsold EOS-1D Mark III units from your stock."

The Mark III isn't the only canon digital camera with quality control problems. Earlier this month, the company issued a service notice on its Powershot A650 IS 12-megapixel bytecam.