THE ProPlus doesn’t go in much for graphic displays. There’s one to indicate ascent rate and another for nitrogen absorption.
I didn’t miss the graphics, because I prefer to read information. I simply find it easier to take in, especially in the narcosis zone, where I tend to really concentrate on my read-outs.
The unit is highly customisable. A fundamental choice is which of two algorithms you favour. Oceanic was an early adopter of the DSAT algorithm developed in the late 1980s for the PADI RDP, though it has been somewhat modified for decompression diving, which the RDP did not allow.
Technical divers have leaned towards Buhlmann-derived decompression models, so the ProPlus also offers Pelagic’s proprietary Z+ algorithm, which originates from the Buhlmann ZHL-16c schedule.
The DSAT model provides more generous no-stop times, but will penalise you for deco-dives with longer stops or shorter subsequent no-stop times than the Z+. The Z+ uses more conservative no-stop limits but is less restrictive for deco exposures than DSAT’s schedule.
The side-reading compass is a floating-card model. As on the computer, the digits are large and easy to read.
Oceanic points out that having these two programs should allow you to match your ProPlus to most other computer brands. This can be helpful if you want your dive-times to roughly match those of a buddy using a different make. It also offers flexibility when shifting from recreational diving to tech, which, with a change in training agency, might also mean changing to different deco conventions.
For additional peace of mind, you can choose various levels of conservatism, to make you feel happier (to be PC about it) if you are of mature years, genetically big-boned or both.
This is because being old affects your circulation and nitrogen loves fat. Both factors alter how nitrogen is absorbed and released, putting you outside the test criteria for dive-tables and computer algorithms and raising your risk of decompression illness.
Deep stops are another option, with an early-warning system to let you know that you’re approaching the stop level. Altitude is set automatically.
Then there’s a long list of choices such as whether you want imperial or metric displays and how long you want your backlight to stay on when activated and whether you want any of more than a dozen audible alarms to sing out or not. Once you’ve set these options, you’ll probably leave them alone.
Other alarms you might want to set on a dive-by-dive basis. A depth alarm can be useful when descending a wall, for example, when it’s easy to get carried away.
You can also set a timer to help you stick to a plan.
The gas-integration lets you program in a turn-around alarm based on tank pressure, which can serve as a reminder to let a divemaster know that you’ve used up, say, half your tank.
Backing this up is a secondary reserve alarm that can be set between 20 and 105 bar, to help you avoid running out of gas or arriving back on the boat with so little air left that you incur the DM’s wrath.
Yet another alarm can be selected to go off when you reach a certain percentage of your remaining no-stop time. It’s all good, safe stuff.
You can simulate dives on the surface to see the effect that changing depth, time or gas mix will have, with a simple planner that lets you see no-deco times for a selected depth. You can’t simulate decompression dives to see what hang-time you’ll incur ahead of the dive.
A comprehensive built-in log-book holds 99 dives – you can upload to Diverlog+ using Bluetooth. Oceanic has chosen to go with a user-changeable CR2 battery. A low-battery warning gives you plenty of time to make the switch, assuming that you have a spare.