OK so what are the advanages of NITROX? Recently I'd been diving with a partner that used NITROX. I don't what mix but the max depth for the dive was 120fsw. I dive with air. When my bottom time was at 10 min left I infromed him of that fact. He showed me his PDC it indicated he had 13 min bottom. WTF around here a NITROX costs $30.00 air is $7.00. What advantages does one get for the extra $27.? What is the NITROX advantage?
OK, I started with post #61 so I am violating a very good rule of thumb, but there are many x factors to consider to give a proper answer to the question quoted above.
Are they the same model computers, with the same personal settings? Was your buddies computer in Nitrox mode? Some divers dive Nitrox in Air Mode and supposedly consider the benefit to be a reduced chance of DCS. I have also seen Nitrox divers enter 30% into their computer for 32% gas, for various reasons.
Were you joined at the hip and horizontal the entire dive, with computers always the same depth? Perhaps he spent a little extra time below you. Was this the first dive of the day, with no late night dive for him to affect his computers calculations? If not the first dive of the day, were you similarly joined at the hip for the previous dive(s)?
The more details you give the closer to correct the answers.