If you’re familiar with the Shearwater Research NERD 2 computer, you likely know about it because of it’s use in closed-circuit rebreather diving. With a rebreather, the NERD (near eye retina display) is an amazing device that attaches to the diver’s loop and sits directly below their eye. The diver is able to see a small screen that shows all the same screen components as the larger computer sitting on their wrist. This is particularly helpful for rebreather divers because they are constantly monitoring their PO2 on their computer during their dive. Having this information within the diver’s field of vision at all times is incredibly helpful in operating their unit (and therefore keeping them alive lol). While I believe the NERD 2 is an invaluable tool for technical rebreather divers, there is also a place for this computer in open circuit diving.
Shearwater makes a separate model of the computer called the NERD 2 SA (Stand Alone). This particular model clamps onto the diver’s second stage regulator hose, and displays the same screen they would see on any open circuit Shearwater product. But with a price tag significantly higher than other open circuit Shearwater computers, what real benefit does an open circuit diver gain by sitting the computer directly under their eye, when a quick lift of their wrist will show them the exact same information?
So the answer to that is the digital compass.
Let me pause for a moment. If you don’t use a DPV (scooter) in open water, you’re not a fossil diver or you’re not someone who is just into gadgets, this is your stop. (This computer probably won’t impress you…. Check out this one instead: Shearwater Research Perdix 2 computer.)
If you’re still with me. Let’s talk about the compass. As a recovering “cave-only” diver, I didn’t have much use for a compass in my diving journey. When I started diving for fossils, I had to brush up on my navigation skills. I have found the digital compasses on (all) Shearwater products to be reliable, and I’ve stopped carrying an analog compass for that reason.
The NERD 2 has the same digital compass as the other Shearwater computers, but putting it against your eye gives both DPV and Fossil divers advantages for different reasons.
DPV benefit: Its easy enough to mount an analog (or digital) compass on your scooter, however depending on where you mount it, you may have some interference with the electronic components of the vehicle. I don’t think I need to explain why that is an issue lol. Wearing a NERD 2 on your second stage moves the compass far enough away that you don’t have those interreferences. (Its possible your experience may differ, but I have found this to be the case with my diving.)
Fossil diving benefit: Hands free bitches! Lol. Having to hold your compass in the exact right position takes a hand away from your fossil collecting, not to mention it can be uncomfortable if you’re wearing a wrist-mounted compass and need to hold a heading for the majority of your dive. When the compass is sitting just under your eye, you don’t have to worry about positioning it, or taking the few seconds to orient yourself. You just glace down from time to time and you’re golden.
“But wait, Tracy, doesn’t the screen get in your way and keep you from seeing fossils?” Not at all. In fact, you have to remember to look at the computer to see it, otherwise it just blurs out of your vision like optical magic.
If you don’t believe me, here are all the fossils I found on a recent fossil charter with Top 2 Bottom charters in Venice. I didn’t find all of that with just one eye lol.
There are a couple of things to keep in mind if you decide to buy this computer.
1. There is an internal rechargeable battery. This is becoming more common with dive lights, so remembering to charge your gear before a dive is less of a burden these days. The NERD 2 also comes with an external battery to add juice to your computer if you are on a longer trip, but the battery lasts a decent amount of time. I get 6-8 90 minute fossil dives on my computer before I have to recharge.
2. There is a short adjustment period to position the NERD 2 right where you want it. This took me one dive/adjustment, which was easily done on the dive boat during a surface interval without the use of tools. I’m only mentioning this because I don’t want someone to open the box and throw the computer on your reg and expect not to have to mess with it juuuust a little bit. But for me, this was a quick set-it-and-forget-it situation.
3. With a price tag of $1650, this is going to be one of your more spendy gear investments for your open water kit. I still found it to be well worth it to have my hand free and my compass oriented for the entire dive. Don’t forget to use the attached tether string on your regulator hose. This will keep you from losing your investment if something happens to the mount mid-dive.
There you have it. The NERD 2 stand alone is a great tool for open-circuit open-water DPV or fossil divers. If you find yourself regularly participating in one or both of these small subsets of diving, definitely take a look at this computer.
As always, Safe diving!