Subsurface is an open source divelog program that runs on Windows, Mac and Linux.
With Subsurface the user can download dive information directly from a large number of supported dive computers. Subsurface is able to track single- and multi-tank dives using air, Nitrox or TriMix. It displays a dive profile with all related information, including air consumption and alarms. It also allows logging of information like weights and exposure protection used, dive masters and dive buddies and enables the user to rate dives and provide additional dive notes.
With Subsurface the user can track dive locations including GPS coordinates (which can also be conveniently entered using a map interface). Subsurface calculates a wide variety of statistics of the user's diving and keeps track of information like the user's SAC rate, partial pressures of O2, N2 and He, calculated deco information, and many more.
Subsurface allows the user to print out a detailed log book including dive profiles and other relevant information. The program is localized in more than a dozen languages and well supported by an active developer community.
One of the major strengths of Subsurface is its support of a wide range of dive computers (most common dive computers are supported, a detailed list is at
http://subsurface.hohndel.org/documentation/supported-dive-computers). Subsurface can also import existing dive logs from several sources including MacDive, Suunto DM3, JDiveLog and divelogs.de. Another strength is its ability to visualize the depth profile (and, if available, the tank pressure curve) in very innovative ways that give the user additional information on relative velocity (and momentary air consumption) during the dive through the coloring of the graphs."
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