Canon has discovered that images taken by some EOS-1D Mark III and EOS-1Ds Mark III digital SLR cameras may exhibit ring-shaped spots and is now offering free inspections and cleaning to solve this phenomenon.
The phenomenon is that some of the images taken with some of the cameras may exhibit large ring-shaped spots. These ring-shaped spots are the images of oil lubricant on the surface of the low pass filter (LPF), which is located in front of the CMOS sensor.
The oil is used inside the mirror box to lubricate some of the camera's moving parts. If the oil is applied too liberally when the camera is manufactured, it can become scattered onto the surface of the LPF through normal camera operation.
Canon asks that customers who are encountering this phenomenon, or who have noticed that oil is visible on the surface of the back side of the mirror, should please click here to complete an online registration form if you own an affected product and wish to arrange for an inspection and clean. To prevent oil from scattering, which may seriously affect images, Canon will offer free cleaning of the mirror box to affected customers to remove the excess oil.
Measures are being implemented to control the amount of lubricant applied during manufacture in order to reduce the occurrence of oil spots. However, because this lubricant is required to ensure proper operation of the camera’s precision mechanical parts, it is impossible to eliminate all instances of oil scattering. If you require CMOS sensor cleaning, please click here to complete an online registration form if you own an affected product.
Canon offers its most sincere apologies to customers using these products who have been inconvenienced by this issue. Going forward, Canon will spare no effort in its quality management to make sure its customers can use its products with confidence. Canon hopes its efforts will earn your understanding.