RULE FIVE:Never dive with something you can't afford to lose or jettison. ;-)
Off of NC, we often need two hands to ascend/descend and get back on the boat. I use a d-ring on the camera, a d-ring ring on my harness, a carabiner hooked on that d-ring, with a webbing connected brass clip attached to carabiner. the brass clip hooks to the camera d-ring. The camera can come off easy, if needed; The clip can come off me, easily, if needed; I usually keep the rig connected to me during the entire dive. It gives me enough play to bring it up to shooting position, etc. I dive with my neoprene cover on the dome and take it off once I am settled/comfortable, so in a current I let the housing just dangle behind me as I "climb" down the anchor line.
After 30 years, no issues, no lost housings. I used to actually dive with up to 4 stromm housings this way, back in the film days. (no strobes though!) I find that attaching the camera to your body while diving is the only way to ensure if I get to that "me or the camera" decision, I will make the smart choice, not one based on gadget value...gadget insurance is what that is for. You can always buy a new housing/camera or dome port;
We do the pass off of the camera to the mate while at the surface, hanging on the deco line at the stern of the boat. You let go when you feel and see him take it from you. Likewise when the camera is handed to the diver in the water.
If you can climb a ladder of a small boat in a 6+ ft swell with doubles and your camera attached in front of you without smashing the entire rig, you are certainly a *much* better person than I. I would lose at least a dome housing on every dive
