Canon has finally updated the firmware for the EOS 5D Mark II in order to address the famous black dot and vertical banding problems. See the notes from Canon below regarding Firmware Version 1.0.7

Firmware Changes:

Firmware Update Version 1.0.7 improves and mitigates the following two types of image quality phenomena that occur under certain shooting conditions.

1- "Black dot" phenomenon (the right side of point light sources become black)
2- Vertical banding noise

Firmware Version 1.0.7 is for EOS 5D Mark II cameras with firmware up to version 1.0.6. If the camera's firmware is already version 1.0.7, it is not necessary to update the firmware.

Notes:
When updating to Firmware Version 1.0.7, please also update the Digital Photo Professional and Picture Style Editor software. Firmware Version 1.0.7 can be downloaded from the bottom of this page. Updates for Digital Photo Professional and Picture Style Editor can be downloaded from the following Web site.

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