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Hi Valentin,
I believe that many recreational dive computers (designed primarily for no-stop diving), operate essentially by simply limiting the equivalent of the surfacing gradient (GF hi). They give you a stop ceiling of 10 feet until that is no longer adequate, then add on time with a stop ceiling of 20 feet, then 30 feet, etc. That is how my Oceanic computers work. The conservative factor adjusts the altitude to the next higher segment rather than directly changing the surfacing criteria. There is no mechanism for my Oceanic computers (a VT3 and a Geo2) to change the stop ceiling (10 or 20 feet) or to add deeper deco stops (i.e. adjusting the GF lo). My VT3 runs only DSAT whereas my Geo2 runs either DSAT or PZ+ (Buhlmann ZHL-16C). There is little specific information in the Oceanic manuals covering this information. It is a good thing to understand how your computer works, particularly for understanding its weaknesses. If I were to do more than occasional light deco, I would certainly switch to a computer designed so that I could control my deco profile.
Of course, there is also very little in the Mares manual covering these topics for your Matrix. It runs a proprietary Mares-Wienke RGBM algorithm and may control surfacing in a different manner. The conservative factors P1 and P2 are not described. I see no mechanism to set the last stop ceiling.
There is a well written introductory article on gradient factors in this month's Alert Diver, by Neil Pollock Alert Diver | Gradient Factors
Good diving, Craig
I believe that many recreational dive computers (designed primarily for no-stop diving), operate essentially by simply limiting the equivalent of the surfacing gradient (GF hi). They give you a stop ceiling of 10 feet until that is no longer adequate, then add on time with a stop ceiling of 20 feet, then 30 feet, etc. That is how my Oceanic computers work. The conservative factor adjusts the altitude to the next higher segment rather than directly changing the surfacing criteria. There is no mechanism for my Oceanic computers (a VT3 and a Geo2) to change the stop ceiling (10 or 20 feet) or to add deeper deco stops (i.e. adjusting the GF lo). My VT3 runs only DSAT whereas my Geo2 runs either DSAT or PZ+ (Buhlmann ZHL-16C). There is little specific information in the Oceanic manuals covering this information. It is a good thing to understand how your computer works, particularly for understanding its weaknesses. If I were to do more than occasional light deco, I would certainly switch to a computer designed so that I could control my deco profile.
Of course, there is also very little in the Mares manual covering these topics for your Matrix. It runs a proprietary Mares-Wienke RGBM algorithm and may control surfacing in a different manner. The conservative factors P1 and P2 are not described. I see no mechanism to set the last stop ceiling.
There is a well written introductory article on gradient factors in this month's Alert Diver, by Neil Pollock Alert Diver | Gradient Factors
Good diving, Craig
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