It seems some users are experiencing a weird sensor issue with their Canon EOS 5D Mark IV.
The issue was first discovered by Michael Andrew. He noticed sort of ghosting artefacts across the frame while doing some dynamic range tests. You can see the artefact in the image above. It is a horizontal banding going across the entire frame.
He discovered the following:
- The defect doesn’t happen on a 5D3, A7rii, Nikon D500 or Fuji XT-2 under the same conditions.
- It only happens on the very far left 1/3 of the frame when over-exposing a certain amount of it, about 1/4-1/3 of the frame, and it typically needs to start on the very far left side, and extend minimum about 1/4 into the frame. Overexposing in the center, the right, or smaller portions of the left side have no effect and seem normal.
- The defect is strictly horizontal, even when the over exposure is oriented diagonally.
- The defect is not visible until raising the shadows. You won’t see it until then.
For the time being it is unclear how many Canon EOS 5D Mark IV models are affected by this issue. If you want to check yours, proceed as follows:
- Use your hand or a piece of cardboard to over-expose in the left 1/3 part of the frame shooting RAW
- Bring the file into Camera RAW
- Bump up the exposure +1 or more (this makes it easier to see)
- Raise shadows. It will look like the images below if you have it:
The video below introduces you to the issue and how to test for the thing. More information and pictures of the phenomenon can be found on Michael’s site.
Canon EOS 5D Mark IV at a glance:
At a glance:
- 30.4MP Full-Frame CMOS Sensor
- DIGIC 6+ Image Processor
- 3.2″ 1.62m-Dot Touchscreen LCD Monitor
- DCI 4K Video at 30 fps; 8.8MP Still Grab
- 61-Point High Density Reticular AF
- Native ISO 32000, Expanded to ISO 102400
- Dual Pixel RAW; AF Area Select Button
- Dual Pixel CMOS AF and Movie Servo AF
- 7 fps Shooting; CF & SD Card Slots
- Built-In GPS and Wi-Fi with NFC