Thank you, ksporry, for that blast. I realize I was one of the people who, instead of giving you constructive advice, simply told you to wait. You are right; that isn't very helpful.
I assume you have found the 5thD-X videos on YouTube (and Dan's video also gives you a visual). Good horizontal trim helps to keep your fins out of the sediment, which reduces the particulates to cause backscatter. Kicks like helicopter and back kicks allow you to follow a subject, but the basis for all of this is being able to sit perfectly still in the water. This requires both control of body posture and balancing of equipment.
THIS article has some good information on setting up body posture for stability, and the article on the same site on horizontal trim expands the ideas.
Of course, once you add a camera to the mix, you have upset the applecart. If the camera is not neutral, then holding it out in front of you gives it a fairly long lever arm to affect your stability in the water -- so even small deviations from neutral can have surprisingly large effects. My camera is very slightly negative, so that it will hang beneath me rather than floating up over my head (where I can't see what mischief it is getting into). Even this slight amount of weight, when held out at arm's length, has put my trim off, and since I began using the camera, I have to work hard not to go a little head-up to compensate. You can see the problem here:
It's not a big issue when we're in midwater, as where that photo was taken, but becomes far more of one when shooting very close to the bottom. Many of our macro subjects in Puget Sound are bottom-dwellers, so it's very relevant to us to keep the sediments undisturbed.
So, although it's often desirable to have the camera SLIGHTLY negative, it's a good idea to add floats until it is only VERY slightly negative, so that you aren't trying to cope with a very large lever arm.
The second huge problem that photographers have is situational awareness. No matter who you are or how you are trained, you WILL dive into the viewfinder and lose awareness of your surroundings for a period of time. What's really important is to be aware of the passing of that time, and not allowing it to become overly long (unless, of course, you are solo diving). In a target-rich environment, it's also possible to get so excited and distracted that you forget important things like checking depth and gas pressure. The way to deal with this is to build in a VERY strong and habitual sweep of the important information of the dive -- one of my instructors gave me the mantra, "What's my depth? Where's my buddy? Look at the fish . . . " and although simplistic, it's the basic idea. Discipline yourself to check your depth, time, position in the water, relation to buddy or other divers (or guide), and pressure at determined intervals. You will eventually get to where you start to "itch" if you haven't done your sweep for too long . . . I can only hunker down on a subject for so long before I have to look up and see what is going on around me.
In addition, dedicated photo dives can be set up to where the buddy or buddies are aware that the photographer's purpose for being there is to shoot, and they are diving support -- scouting for critters, providing off-axis lighting, or working as models. In that case, the buddies may assume some of the situational awareness responsibilities for the photographer. But nobody else will ever be checking YOUR gas!
I think the reason I was so negative at the beginning is that most of these skills take time to ingrain. You are very right in saying that handling a camera can really show you the weak spots in your basic diving skills -- we actually encourage AOW students to do an underwater photography dive for this very reason! It does complicate getting your posture and trim right, though, when you are deliberately perturbing it before you've gotten it right without the camera, so progress may be quite a bit slower.
Thank you for pulling me up short. Your post will change the way I answer this type of question in the future.
