Hi Folks,
I've noticed shadows/black corners appearing on photos from my Canon 5Diii & Canon 100-400L lens...especially on bright sunny days.
With lens hood on or off, focal length used, seems to make no difference.

Any body else had same issue or got a solution?

Many thanks
Dave

Example:
https://www.flickr.com/photos/jaffapix/14858313519/...