My SAC is really bad.

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I'd leave the video camera at home for a while. You have enough things to worry about without using up mental bandwidth on filming.
 
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I haven't read through the posts, but I suspect these are listed. Here's what improved my air consumption tremendously.

1) streamline your gear. Take nothing you don't need, get everything strapped up, put anything else in pockets (Leg pockets)
2) Exercise. Get lots of cardio and some muscle building workouts in. Cardio helped me the most.
3) get your weights set correctly. Too heavy and you'll be pumping BC (or wing) air in and out constantly. This causes other issues, too so get it right.
4) relax and wear warm thermals. Being cold makes me breathe faster. Stress makes me breath faster.

That's my secret and it's worked well for me.


dv:
I've just started using dive logging software and downloading my dive profiles from my DC, using MacDive and the Dive Log iOS app. I knew I was bad on air and maybe it's normal for someone so new (< 20 dives), but it became immediately apparent to me that I am not only bad on air, I am really quite possibly the biggest air hog on the planet. On my best day I'm around 1.1 cf/min, but this year I'm posting numbers like 1.6 cf/min! On my last dive we were down 19 minutes, and I had to turn back because I was down to 1000 psi (avg depth was 48 ft, started with just over 3000). I was using a Steel HP 130 tank, and I got 20 minutes out of it?! My buddy used an AL80 and ended up with more air than I had left. Out of all the people on this board talking about SAC rates, i've never seen any as bad as what I am recording.

One thing I am doing differently this year is that I am diving dry. Not sure if that is causing this dramatic increase in SAC.

I'm not sure what to do about it really. It's really starting to cause me stress while underwater now, and I'm checking my gauge like a crazy person. I'm sure that is not helping.

Help is appreciated!
 
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You would be surprised how much air you lose to surface freeflows, a few seconds of that is equal to 5 or 6 good deep breaths. Plus, you seem to be a pretty new diver (based on the number of dives your profile says :) ), so I wouldn't worry about it. All "newbies" use a good bit of air. I averaged quite a bit of air (don't know full value) when I was relatively new to diving. I actually had to change out tanks halfway through my checkout dives :dork2:


Don't sweat it, remember that using rental equipment generally means they wil freeflow at the surface, and adding and taking air from your drysuit/BCD will also use a ton of air, especially to the new diver that isn't used to trim and buoyancy control. Also, as you become more relaxed in the water, you'll begin to NOTICE yourself using less and less air. You may be "comfortable" and think you are as relaxed as you can be, but everyone has a long way to go, even DIR and GUE :p :p :p

Just relax and enjoy it, the more you try to use less air, the more you'll use!
 
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I have to say, I'd definitely recommend leaving the camera at home until you get your gas consumption under better control. I don't get mad at new divers who use gas . . . but I'd be seriously annoyed with someone with a video camera who cut MY dive to 20 minutes (assuming you have one of those dive operators who make everybody go up when the first person hits gas).
 
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I have to say, I'd definitely recommend leaving the camera at home until you get your gas consumption under better control. I don't get mad at new divers who use gas . . . but I'd be seriously annoyed with someone with a video camera who cut MY dive to 20 minutes (assuming you have one of those dive operators who make everybody go up when the first person hits gas).

Yeah, I was just testing the camera for a friend. I don't actually own one. And after this experience, I am not going to buy one until I got this stuff figured out.
 
I remember doing underwater digital photography back when I got my AOW as one of the choices, and he pretty much just gave us his camera and said "have fun." My buoyancy seriously suffered. But then again, what better to help you get better acquainted with buoyancy than a camera to juggle with at the same time
 
dv - Here is another possibility. You may have a regulator that is very easy to breath. When you breath in and get the flow going, the reg can continue to deliver air, even though you have stopped breathing in. The excess air comes in through your mouth and flows out your nose. This "gentle free flow" can use a lot of air. If you notice this happening, just stick your tongue in the mouthpiece to stop the flow. You may also close the passageway between the nose and mouth.

Relaxing and calm, deep breaths will help too. Good luck!
 
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One thought.. Are you using your lungs as your primary means of adjusting buoyancy? If so you will increase your sac by over breathing for finite control in the water. It's subconscious. I would consciously work to use your bc as your primary means of control, leave the dry suit as empty as possible and only use enough gas to relieve the squeeze. Try to use small adds and dumps on your bc rather than making large corrections and all time for it to settle in before making further corrections. It's like driving a boat the changes you make have a delay before they start.
 

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