Is rear inflation better for underwater photography?

[RoadWarrior]

Is rear inflation more stable underwater and better for photography?

I've been diving on and off for many years. My new room mate likes to dive so I'm getting back into it. She and I are going to Cozumel in a couple of months and I'm thinking about buying a BC. Maybe I should qualify that from 1990 through 1998, my married years, I logged about 350 dives. Since then I get about 10-12 dives a year.

I like the look and feel of the Zena but should I consider the backplate style? Cost really isn't an issue.

Is one better than the other for what I'm planning to do?

cj

 

[RiverRat]

I went right to a backplate/wing (back inflate) right after my AOW dives and never looked back. The back inflate keeps your body in a nice horizontal trim. Most of your dive you should be horizontal anyway. I'm able to do barrel rolls, dive inverted, on my back, whatever with no problems. I like the simple, streamlined harness and the "heavy" D-rings for attaching stuff. With the backplate I'm able to put between 3 and 11 pounds of weight over my buoyant lungs. Less lead on my waist. The backplate also holds the tank "tighter" to my body, no shifting or rolling like with a conventional BC. This makes a BIG difference when trying to compose shots. In addition to back inflate BC's take a look at something like Dive Rite's TransPlate and other backplate/wing systems. There is an excellent article in the June 2005 edition of Scuba Diving magazine.

 

[BILLB]

Rear Inflation. One can really put the imagination to test! Sorry, but no pun intended!

Back inflation works very well. I do video work and back inflation gives me unlimited possibilities including swimming backwards on my back. If so inclined, a backplate can also improve this experience.

 

[drbill]

Shortly after I started U/W video several years ago, I switched from a jacket to a soft backpack and wing (SP X-Tek). I've never looked back. I find this design is perfect for my videotaping.

I use a TravTek wing (under 30# lift) in cold water and it gives me sufficient buoyancy even when I'm over-weighted (which I do to remain stable while filming on the bottom). I'm "flirting" with BP/W as well, having just purchased an aluminum BP that will accommodate all my wings as well. Such flexibility with these systems which is great since I dive in a number of different kinds of conditions and travel as often as I can.

Somehow the lyric "You are the 'current' beneath my wings" comes to mind. Didn't Bette Midler sing that? I didn't even know she dove!

Dr. Bill

 

[RoadWarrior]

Is it that the air is on top of me when I'm facing down? Is that what adds to the stability of a rear/back style BC? I can see why the tanks might fit more snugly fastend to a plate that's strapped to my back but moving the weight an effective 6 inches futher up my back (that's opposed to a weight integrated BC) doesn't seem like it would have much effect on anything.

I used to dive quit often and don't remember having any of the shifting & rolling problems you mention. My old BC, I don't have it anymore, had 2 straps in the back. Maybe that's why the tank held in place better.

I only need 6 pounds anyway and if diving in my skin 4 pounds works. I really wanted to ditch the weight belt. I know you can get those weight integration systems for the Transplate because I went and looked just now but if I'm doing that isn't the whole purpose of the backplate defeated?

Thx, cj

I went right to a backplate/wing (back inflate) right after my AOW dives and never looked back. The back inflate keeps your body in a nice horizontal trim. Most of your dive you should be horizontal anyway. I'm able to do barrel rolls, dive inverted, on my back, whatever with no problems. I like the simple, streamlined harness and the "heavy" D-rings for attaching stuff. With the backplate I'm able to put between 3 and 11 pounds of weight over my buoyant lungs. Less lead on my waist. The backplate also holds the tank "tighter" to my body, no shifting or rolling like with a conventional BC. This makes a BIG difference when trying to compose shots. In addition to back inflate BC's take a look at something like Dive Rite's TransPlate and other backplate/wing systems. There is an excellent article in the June 2005 edition of Scuba Diving magazine.

 

[BILLB]

With a steel Backplate (Diverite) you will need no weights. Go with a steel tank and you will never need weights.

 

[BILLB]

The mechanics of back inflation varies with the type of "wing" used. Some are floppy, some are formed shaped and some are just right! Staying horizontal is the "wing" best feature. If the wing is oversized, then air trapping is a problem. If you are diving a single tank, then check out both the Oxycheck and Halcyon single tank wings. Divers swear by them! The Dive Rite gear is also good, but the wing will wrap around the tank when depleted and this only results in probably a little more drag. Dive Rite does has a "gusseted" wing but I am adverse to this idea. There are many posts on this subject also known as "bundged wings" with both pro and con opinions.

The back plate arrangement is also a personal choice. I have dove with a single tank and back plate and with a Seaquest Balance. Both give me the back inflation and stability even when diving 120's. I use the backplate because of the ease of changing from single to double tanks. Again, this is a "hot" subject so check out the posts and make an informed decision.

 

[divewriter]

In my experience, back-mounted buoyancy systems - backplate or integrated - are not inherently superior in terms of stability, as compared to a well-designed jacket with open air cell design. However, back-mount systems can easily be trimmed and adjusted to provide excellent horizontal and reasonable vertical stability. But that isn't the issue with regards to use for underwater photo work.

Real advantage of keeping the air in back and only a harness in the front is the uncluttered forward profile and (typically) numerous attachment points such systems provide. Both qualities become important when you are swimming a larger housinng and/or managing accessories. Upsides of backplates/wings have been detailed by others. Downsides includesize and weight when traveling, and somewhat greater difficulty (for most users) of donning and removing, particulary when in the water. Several divers I know have used and loved the Zena.

 

[RiverRat]

Downsides include size and weight when traveling, and somewhat greater difficulty (for most users) of donning and removing, particulary when in the water. Several divers I know have used and loved the Zena.

I'd have to respectfully disagree on the size and weight issue while traveling. I have a heavy 9# plate I use but I also have a 1# Aluminum plate if weight is an issue. I had to get the AL plate because wreck diving in NC with my steel tanks and 3mm shortie made me too heavy with the 9# steel plate. I disassemble the plate and wing (Oxycheq 45# standard wing) and pack them in a bag I have that has several vertical "slots" if you will. The wing folds up about the size of a newspaper and I wrap it in a towel. The plate goes in the center slot of my bag with some other items. Yeah it's a little hassle breaking it down and putting it back together but it's only 2 bolts/wingnuts and I have to re-thread the tank straps. Try that with a conventional BCD. Another upside to my setup is the dual tank straps. No chance of tank slippage and the end of the tank will not bob up and down. For warm water diving with a light wetsuit aluminum may be the best bet. Steel if you don't want a weightbelt.

 

[RiverRat]

Is it that the air is on top of me when I'm facing down? Is that what adds to the stability of a rear/back style BC? I can see why the tanks might fit more snugly fastend to a plate that's strapped to my back but moving the weight an effective 6 inches futher up my back (that's opposed to a weight integrated BC) doesn't seem like it would have much effect on anything.

Yes to the first question. Well sort of.... If you are weighted properly you should need NO AIR in the BC/wing. You should sink on exhale and rise on inhale throughout the water column. When I'm diving warm the wing is there for emergencies really. Getting positive on the surface or to get out of some life threatening situation at depth. With the 3mm shortie suit compression is minimal so I don't need the wing to compensate for that. When I dive a 7mm it's a different story.
Keep in mind you're not just moving the weight 6 inches further up your back but you're also spreading it out over say a 1 foot square area, basically right over your lung area. Think of it like this. Draw a profile picture of a diver horizontal. Now draw buoyant lungs (up to a 12# balloon) at the front and a heavy weight belt, say 12# at the "rear". See the concept? Front of diver buoyant and rear of diver negative. Tendancy for your trim or attitude to be head high, leggs dragging. Now add a 9# plate and dive 3# on your belt. More balanced diver. Better trim. Now this may not make as much of a difference for lighter weight divers but for heavier folks this can make a big difference. Same idea for a conventional BC too. Use trim pockets to basically move weight off the hips. I have dove my 9# plate with AL tanks and 3# belt and my 1# plate with AL tanks and 10# belt and basically did not notice a major change to my trim. I would have to compare side by side to see. But I do like diving the 3# belt over the 10# belt any day.

I used to dive quit often and don't remember having any of the shifting & rolling problems you mention. My old BC, I don't have it anymore, had 2 straps in the back. Maybe that's why the tank held in place better.

I'm sure the 2nd strap was key to holding down the bottom of the tank.

I only need 6 pounds anyway and if diving in my skin 4 pounds works. I really wanted to ditch the weight belt. I know you can get those weight integration systems for the Transplate because I went and looked just now but if I'm doing that isn't the whole purpose of the backplate defeated?
Thx, cj

With my rig the AL plate is 1# and the steel tank adapters are 2# (2 piece) So that's 3#. So if you had a comparable rig you would still need 3# somewhere. The idea of reducing ditchable weight is only one plus of the system. Some may prefer a small amount of weight "integrated" versus on a belt. Also keep in mind BP/W setups have NO inherent buoyancy whereas most BC's have between 1-5 pounds of buoyancy due to the padding in them. More weight you won't need.