@Asanoth Have you tried a few dives without the camera to see if your gas consumption rate improves? Based on my experience and my dive buddies', we all tend to consume more gas while carrying cameras and chasing the interesting shot. My friends and I find that diving camera-less leads to a more relaxed dive and improved gas consumption rates.
Yes, so I have been told, but for me it is nearly pointless diving without a camera. Definitely way less enjoyable. I dive to see (and record observations of) underwater fauna, and being a vacation diver from landlocked country, every single dive is precious to me. Since I have had an OWD, I have only done 3 dives without a camera, as I did not expect to be diving and did not have it with me, but I also did not have my computer and did not log average depth. I do not recall my air consumption being significantly lower though.
Interestingly enough, my first 20 dives after my certification, my average SAC was 17,1 l/min.
After that, I did a short liveaboard in Komodo, 17,4 l/min.
Liveaboard in Egypt, 17,4 l/min.
27 dives on (in? at?) the Philippines this January, 17,2 l/min.*
It changes 14 - 21 (those are fairly atypical, mostly 15-20), but my average SAC has not changed since I did my OWD.
Consensus seems to be, that I am moving too much. I do not really feel I move at all, but that is what people tell me. One Filipino dive master told me: Everything is good, your trim is good, your buyoancy is good, but you move too much.
I actually had fairly poor neutral buyoancy (and understanding of what neutral buyoancy means), using legs quite a lot to balance, but after watching some Flowstate videos mid this Philippines trip, I immediately fixed this, at least to a significant extent, also went from 3 kg to 2 kg weights (I am some 70 kg and fairly slim), and a few dives later moved one kg on my tank to lie flatter.
I also changed my breathing: before I was taking really deep breaths, say 10 - 90% capacity, which I tried to switch to the Flowstate recommended 40 - 60 % when not changing depth. This was not as quick to fix and sometimes my mind wandered off it.
I really expected my SAC will jump down after this, but it did not change at all (actually those dives are 0,5 l/min worse, but those were not lab conditions, so such small difference does not play a role, I think).
That same DM actually said that as I have legs up, I might be underweighted (which does not correspond to the BC out - breath in - eye level surface test). Maybe it means I am not stable depth-wise. My wife also told me that often after I take a photo, I rise up "like 2 meters".
During our time in Anilao, a videographer from the US joined our group: He was often kicking A LOT (churning sand and sediment big time, sometimes), he had a very heavy rig, but still his air consumption was apparently very good. I just cannot wrap my head around it...
I guess I just need to realize how and when I move and stop doing that.
* Side not for the Philippines trip: My first 2 days on Malapascua, I had SAC 15,3 l/min (27 - 28 °C). Then I got food poisoning and did not dive for one day, and only did 2 more dives the next day (17 and 18,6 l/min). In Anilao, water was colder, 26 - 27 °C - it does not seem like much, but it definitely felt a lot colder, and I also had some Aliexpress wetsuit instead of Cressi Lui, which fits me very well. Here my SAC was 17,7 l/min.
I also realize that the manometers can easily be 10 % off, so maybe figures like 17 and 18,6 is actually the same.
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