Can't speak for Otter but that's the Perdix Rec setting I use (low conservatism)@sea_otter , could you maybe explain why you would use those particular GF settings (if you're already comparing between them...)?
Past NDL. And then this???
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DevonDiver
N/A
Mentioned repeatedly throughout the thread. It's RGBM.... as also used in Suunto and Mares computers.
That's interesting... and points firmly to a human factor, because other computers on the same dive (Suuntos) didn't go into deco... and... same algorithm folks..!
I'd concur that RGBM is a dire model for dedicated deco dives, but not for the reasons raised in this thread.
Surprisingly, many tech divers would say RGBM stopped you too deep and gave too little shallow phase deco.
RGBM Really Good Bends Model
So your reason for why is because that is the setting on your computer? Do you adjust it based your profiles for a given set of di ves? Maybe to make it more or less conservative, depending on how many dives you are doing? Do you leave it constant?
Dan
Contributor
Just for curiosity, I put OP profile side by side with my 2nd dive of the day with Nitrox-32 in AL80 on the same scale.
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w3dge
Contributor
DevonDiver has already pointed out, multiple times, that you can't compare the results of a dive using VPM or Buhlmann in Subsurface to that of a dive computer using a adaptive algorithm like RGBM. VPM/Buhlmann completely ignores many of the data artefacts that RGBM uses to significantly affect its result.
Compound these over multiple days, with multiple dives/day, and you get this result.
Compound these over multiple days, with multiple dives/day, and you get this result.
sea_otter
Contributor
Ahh.. I see. Apologies for being dense here. Dive computers definitely aren't my forte. And RGBM is some voodoo magic I don't know how it works and I don't have a planner for it so who the heck knows where it comes from greek to me.
But now that you mention it, I do remember one time I made a very sharp dip in my dive profile as I was slowly swimming up a reef (about 8 feet of a sharp V...one of those I know shouldn't really do this but I want a picture of this shark moments). My computer's NDL jumped by what I thought was an excessive amount. I ended up needing to make way up to 30 ft pretty darned quickly to keep my computer from entering deco.
That said, I do remember feeling pretty darned exhausted that trip after 2-3 dives a day over a 4 day trip when I was pushing the limits of my "restrictive" zoop (restrictive based upon stuff like the above, short surface intervals, etc - human factors as Devon Diver would say), so maybe there's something to the algorithm. Anecdotally, I do tend to feel better and have more energy after a very clean ascent profile than after a messy one. Even if the dive itself is less aggressive. No hard quantitative evidence here. Human physiology on this is all kinda crazy weird pseudo science, and I don't want to find out the hard way I landed on the wrong side of a very blurry line.
Reasoning for the choices on the high GF is that I felt 75 (which I think was my computer's default) was too conservative for me, at least for recreational dives. It was cutting my NDL dives much shorter than those of my buddies. I bumped it up to 85. That said, I've never surfaced with it above 70 or 75. My experience here is still very limited. I was also taught to do a 6 minute ascent from 20 ft to the surface on deco dives. This is not included in my dive planner settings, so it basically becomes an added safety buffer (and for the minimal deco I'm planning, makes up the difference between 75 and 85). On GF low, the dives I'm planning aren't aggressive enough for this to factor in much. I've run plans with 20 and 60 and gotten effectively the same results, so 40 is a nice round number. Ascent profile is dictated by training / team plan.
But like I said earlier... though I think it is an interesting subject, I am barely a beginner. I've taken one deco class, done a bit of reading, and I think it's fun to overanalyze dive profiles, but there are folks here with a LOT more expertise than I have. I am not a technical diver. And I certainly don't claim to understand how bubbles work.
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I changed my GF high from 75 to 80 halfway through a week of deep wreckdiving, since my 6m/10ft stops seemed extremely long compared to other divers using 80. The result was pain in my deltoid muscle on the next three deep dives. 5% was obviously already quite a difference for me.
DevonDiver
N/A
Sub-clinical means it's below, or absent, the criteria threshold needed for a medical diagnosis of the ailment.
If it were sub-clinical, then an MD would find no symptoms of an illness/injury and nothing to treat.
The symptoms he describes (joint pain) are not sub-clinical.... they are clinical. They may have led to a DCS diagnosis.
Sub-clinical DCS (aka Decompression Stress) is used to describe the physiological sensations that a diver may feel when decompression is not entirely efficient..... but bubble growth is not extensive enough, or located in the body, so as to present medically definitive symptoms of DCS.
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