Nauticam housings for Nikon and Canon DSLR cameras
Generally, Cathy has preferred Nikon cameras over Canon in the past.
While both brands produce easy to use, high quality cameras, Nikon has long held the edge on ergonomics when the cameras are housed. Above water, Canon is fine, but underwater, historically required extra steps to do simple chores like change the point of focus, or it would not show the blinking highlights in the full LCD monitor.
These create annoying delays and reduce the odds of my getting the best
photo. Given a choice, I went with the Nikon, although with every new Canon model that comes out, Canon is catching up rapidly with the Nikon, so the gap is closing.