Pros and cons of various compasses ?

[Trace Malinowski]

My best compass is a $5 compass I purchased at Walmart a decade ago. It lives in the clear pocket on the back of my wetnotes. If I extend the notebook in front of me, I now have a compass board. I got tired of expensive scuba compasses forming bubbles, leaking, etc. I originally grabbed it for hiking one day when I forgot my good one. I decided to use it for cave survey to see how it worked underwater. Then, both my Ikelite and Suunto compasses both went bad. I switched to just using the Walmart compass. It's been the best since. The only con is that it doesn't work like an airplane compass where I can read through the side window. I have to top read it.

 

[Roger Hobden]

My best compass is a $5 compass I purchased at Walmart a decade ago. It lives in the clear pocket on the back of my wetnotes. If I extend the notebook in front of me, I now have a compass board.

Amusing and efficient. What is the name of the brand ?

 

[Roger Hobden]

For most stuff, however, I just use the electronic compass built into my Perdix and don't carry the physical compass at all.

On which arm do your wear your Shearwater Perdix ?

 

[Lorenzoid]

There is a bewildering array of diving compasses currently on the market.

What are the pros and cons of the most recommend models ?

A "bewildering array" of compasses? I guess I haven't bothered to look at what's out there, because I knew I just wanted a traditional wrist-mounted compass with decent tilt tolerance. As others have said, the DGX compasses work great. The Suunto SK had been the gold standard, but I don't think it offers any advantage over the DGX Pro.

Now I'm curious. What are some examples of compasses that deviate from this style?

 

[Roger Hobden]

Do divers who use a computer compass also bring along another compass just in case the computer floods, for reasons of redundancy ?

 

[Lorenzoid]

Do divers who use a computer compass also bring along another compass just in case the computer floods, for reasons of redundancy ?

If your computer malfunctions, your OW training suggests you should end the dive as expeditiously as possible. There is no need to bring a backup.

That said, I suppose there are some very limited situations where even an OW cannot directly ascend to the surface immediately, such as if you're diving in a shipping lane (St. Lawrence seaway, for example). Maybe those people take backup compasses to get them out in the right direction.

 

[Roger Hobden]

If your computer malfunctions, your OW training suggests you should end the dive as expeditiously as possible.
.

Correct. I was just curious about other divers practices.

 

[stuartv]

On which arm do your wear your Shearwater Perdix ?

The right - where everyone should wear their computer.

I say it with a smile, but I am actually serious. Your left hand is for controlling your buoyancy compensation. You should be able to look at your computer and monitor your depth while you are adding or dumping as from your BCD. It's even more important in a rescue scenario, where you might be attempting to surface with a non-responsive diver. In that case, your left hand will be controlling buoyancy compensation - possibly yours or possibly theirs. And your right hand may be reaching around from behind to hold their reg in their mouth. In that scenario, it really needs to be on your right wrist if you're going to have any chance of monitoring your depth as you ascend.

If your computer malfunctions, your OW training suggests you should end the dive as expeditiously as possible. There is no need to bring a backup.

What if you are on a recreational dive on a wreck and, for safety reasons, you really need to get back to the anchor line before you start your ascent? And if you are relying on your compass to help you find your way back to said anchor line?

As with any other gear in diving, if you NEED it during the dive, then you should give some solid thought to whether to carry redundancy on whatever it is. If your backup is the one your buddy is carrying, then fine. But, make that decision consciously. And in this case, make sure your buddy also takes appropriate compass headings and doesn't just rely on you to get you back to the anchor line safely.

 

[Roger Hobden]

The right - where everyone should wear their computer.

I say it with a smile, but I am actually serious. Your left hand is for controlling your buoyancy compensation. You should be able to look at your computer and monitor your depth while you are adding or dumping as from your BCD. It's even more important in a rescue scenario, where you might be attempting to surface with a non-responsive diver. In that case, your left hand will be controlling buoyancy compensation - possibly yours or possibly theirs. And your right hand may be reaching around from behind to hold their reg in their mouth. In that scenario, it really needs to be on your right wrist if you're going to have any chance of monitoring your depth as you ascend.



What if you are on a recreational dive on a wreck and, for safety reasons, you really need to get back to the anchor line before you start your ascent? And if you are relying on your compass to help you find your way back to said anchor line?

As with any other gear in diving, if you NEED it during the dive, then you should give some solid thought to whether to carry redundancy on whatever it is. If your backup is the one your buddy is carrying, then fine. But, make that decision consciously. And in this case, make sure your buddy also takes appropriate compass headings and doesn't just rely on you to get you back to the anchor line safely.

Very useful advice.

Thank you very much for sharing these considerations. Most appreciated.

 

[Lorenzoid]

. . .

What if you are on a recreational dive on a wreck and, for safety reasons, you really need to get back to the anchor line before you start your ascent? And if you are relying on your compass to help you find your way back to said anchor line?

Dude, did you overlook the second paragraph where I said there are exceptions?