FFW vs to FSW on Bottom Timer/Depth Gauge?
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Tamas
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1atm in fresh water is 33 feet while in salt water 1atm is 34 feet.....so in short 1 foot dfference every atm
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talon4477
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Tamas:
Ok, so in salt water, I follow a marked line down to 68'. My OMS gauge will be reading 66'.
So you plan a dive for FSW.....And shouldn't care about the difference, because the pressure is all your worried about, and even though two different calibrated gauges would read different, you are at same pressure? Or you plan the dive for FFW?
A gauge or computer reading in fresh water will read deeper, not shallower.
In the above example both gauges sense 3 atm of total pressure at 66' in seawater, and the salt water gauge will read 66', but the freshwater gauge displays 68 feet.
For a computer it's of no consequence, because it's not being compared to tables. It's time at pressure that the algorithm is calculating.
Chad
In the above example both gauges sense 3 atm of total pressure at 66' in seawater, and the salt water gauge will read 66', but the freshwater gauge displays 68 feet.
For a computer it's of no consequence, because it's not being compared to tables. It's time at pressure that the algorithm is calculating.
Chad
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talon4477
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The example above is for going down to a marked 68' in salt water(34' ATM X 2=68' actual/salt water), with a gauge that is calibrated for fresh water(33' per ATM X 2=66').Chad Carney:
My FFW calibrated gauge would read the 66', while we are actaully at 68'? Are we saying the same thing?
My BT/Gauge is calibrated for Fresh, but I will be using it in Salt now, so it will read shallower in salt?
Correct me if I'm not getting this correct.
I will not be using a dive computer.
JustinW
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I believe Chad has it correct. It doesn't matter because the computer is calculating time and pressure. The depth is of no consequence to the equation.
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talon4477
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JustinW:
Let me state this separately, because it was overlooked in my other post:
I will NOT be using a dive computer. Only the Bottom timer/gauge and planned tables etc..
NO DIVE COMPUTER. The OMS Bottom Timer/depth gauge has no dive planning/deco calculations.
On the other, do I have this backwards? Will my FFW calibrated gauge read deeper in salt, instead of shallower, as I thought?
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