Went diving the other day and experienced a strange 2 second shutter delay on my Nikon D800 housed in a Sea and Sea housing using a Sigma 15 and then again today with Nikon 16-35.
When I half press the shutter or use the AF-ON button I see that the camera is focusing as my focus points are illuminating, I press the shutter and there is a short delay before the shutter releases. Behaving like a point and shoot.
After the dive I tried at the surface and there was no delay, took the camera out of the housing and again no delay. I also made sure that there was nothing on the inside of the dome port that might cause this. The camera is not set on timer release obviously, the focus modeling light is off, very strange.
Jumped back in for the second dive and the same thing was happening.
Can't figure it out but it must have something to do with the pressure.