Canon is investigating reports of black dots appearing next to the highlights of long exposure images taken on the EOS 5D Mark II camera and will announce its findings in the next few days according to Mike Owen, Canon?s European CCI Photo Products team leader.

There has been much debate on the internet about the phenomenon, which sees black spots edging, or next to, the highlights of images captured with Canon?s latest full-frame DSLR.

Our own research suggests that this problem is limited to some long exposure images and is more noticeable in JPEGs than the simultaneously captured raw files.

The effect is only really detectable when images are inspected at 100% on the computer screen and is visible in images taken both with and without Highlight Tone Priority and Auto Lighting Optimizer.

Canon EOS 5D Mark II black spots

Picture below: Black dots are noticeable to the right of the red highlights

Canon EOS 5D Mark II black spots