For many, the ultimate video rig balance is barely negative for easy control and balance. Many also have a leash or clip tie the housing to the BCD or diver. In some rare instances, one may actually have to release the housing fully and also unleash it. If you do, your negative housing will go down instead of up to the surface for recovery later.
A very simple way is to make a removeable ballast weight that you can easily pull off the housing and let it go. This way, your €$£XXXXX equipment will float up and you can recover it later on the surface.
The ballast weight should be attached by strong industrial velcro and/or duct tape. would put it on top of the housing for easy access. Just make sure the weight nudges your housing into negative buoyancy and that should be enough. To deploy, just pull the weight off (and KEEP it in your BC pocket...no need to litter the seafloor with lead) and then do what you need to do. The housing should pop up at the surface in a few minutes, probably before you do.
For housings that are already negative, I would suggest making it more buoyant so an emergency ballast is easily attached.
This little tip was taught to me by a certain cinematographer who almost lost his rig when a humpback whale smacked him and the housing(digibeta) flew out of the water . The ballast weight fell off and he saved the rig later, after he regained his senses. Without it, he'd have to look for the housing at depth. Not something you want to do when you are near the continental shelf.
