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GPS doesn't work underwater. Would it be for finding your way back to the boat after resurfacing?

mynameisvlad 4y ago
Also for tagging your dives. Your watch would know where you descended/ascended. It’s great for when you’re in the middle of nowhere on a liveaboard and you forget the names of the dive sites. My Suunto watch uses the phone’s GPS for the same purpose.
- scrumper 4y ago
  Yes exactly, it's for tagging dives. Times and locations only, nothing about what happens underwater. Edit: actually my computer does that too, well, the app does sort of: the app I have for capturing data from it takes the GPS location when you trigger a sync. Since I don't sync on the boat (why play with a phone?!) it's not very useful. You can easily edit though, drag a pin around and plop the rough location. MacDive, it's a decent bit of software.
  - mynameisvlad 4y ago
    I use Dive Log[0] which I believe does the same thing, tags when it syncs. Suunto's app as well. I'll usually initiate a sync when I get back on the boat if only to fill in the additional details like island/country/buddy. I started doing it on my first post-OW class dives so it's nice to look back and see all the dives I've done, who I did them with, what equipment I used, etc. [0]: https://apps.apple.com/us/app/dive-log/id301049600 https://apps.apple.com/us/app/dive-log/id301049600
threeseed 4y ago
If you can't see your boat after you've resurfaced something has gone pretty wrong. Most professional divers will be using a Surface Marker Buoy which indicates where they are underwater and where the boat should be looking to pick them up. One feature that would be very useful under water but was disabled was Compass way tracking. Hopefully Apple thinks about it allowing it.
- mynameisvlad 4y ago
  > Most professional divers will be using a Surface Marker Buoy which indicates where they are underwater and where the boat should be looking to pick them up. These are generally deployed only during the safety stop, not for the entirety of the dive for obvious reasons-- handling up to 120ft of line underwater for the length of a dive would be near impossible. They would be pretty useless if you resurface and can't see the boat. That said, you are right, something would have had to go pretty wrong to not see the boat. During a dive trip earlier this year my buddy and I resurfaced 1mi+ from where we were supposed to. But even then, we saw the boat, they saw us and our SMBs and it wasn't a huge deal other than getting the "pickup of shame".
  - nradov 4y ago
    That really depends on local dive conditions. For drift diving in the Gulf Stream off of Florida it's common to tow a float during the entire dive. For tech diving in the Northeast Pacific Ocean we can't tow a float while on the bottom due to rock structures and kelp. But we will shoot an SMB as soon as we leave the structure (rather than waiting until we reach a shallow stop) so that the boat crew can follow us as we drift during deco. Of course it's always a good idea to carry other signalling devices beyond an SMB in case you get separated from the boat.
    - mynameisvlad 4y ago
      I think the only time I've ever seen SMBs used outside of the safety stop are drift dives. And even then, it's been the exception rather than the norm. It's pretty easy to get tangled up if you're doing anything but a single direction drift dive where you're both away from structures and moving in a continuous straight line that doesn't cross itself.

Also for tagging your dives. Your watch would know where you descended/ascended. It’s great for when you’re in the middle of nowhere on a liveaboard and you forget the names of the dive sites. My Suunto watch uses the phone’s GPS for the same purpose.

scrumper 4y ago
Yes exactly, it's for tagging dives. Times and locations only, nothing about what happens underwater. Edit: actually my computer does that too, well, the app does sort of: the app I have for capturing data from it takes the GPS location when you trigger a sync. Since I don't sync on the boat (why play with a phone?!) it's not very useful. You can easily edit though, drag a pin around and plop the rough location. MacDive, it's a decent bit of software.
- mynameisvlad 4y ago
  I use Dive Log[0] which I believe does the same thing, tags when it syncs. Suunto's app as well. I'll usually initiate a sync when I get back on the boat if only to fill in the additional details like island/country/buddy. I started doing it on my first post-OW class dives so it's nice to look back and see all the dives I've done, who I did them with, what equipment I used, etc. [0]: https://apps.apple.com/us/app/dive-log/id301049600 https://apps.apple.com/us/app/dive-log/id301049600

threeseed 4y ago

If you can't see your boat after you've resurfaced something has gone pretty wrong. Most professional divers will be using a Surface Marker Buoy which indicates where they are underwater and where the boat should be looking to pick them up. One feature that would be very useful under water but was disabled was Compass way tracking. Hopefully Apple thinks about it allowing it.

mynameisvlad 4y ago
> Most professional divers will be using a Surface Marker Buoy which indicates where they are underwater and where the boat should be looking to pick them up. These are generally deployed only during the safety stop, not for the entirety of the dive for obvious reasons-- handling up to 120ft of line underwater for the length of a dive would be near impossible. They would be pretty useless if you resurface and can't see the boat. That said, you are right, something would have had to go pretty wrong to not see the boat. During a dive trip earlier this year my buddy and I resurfaced 1mi+ from where we were supposed to. But even then, we saw the boat, they saw us and our SMBs and it wasn't a huge deal other than getting the "pickup of shame".
- nradov 4y ago
  That really depends on local dive conditions. For drift diving in the Gulf Stream off of Florida it's common to tow a float during the entire dive. For tech diving in the Northeast Pacific Ocean we can't tow a float while on the bottom due to rock structures and kelp. But we will shoot an SMB as soon as we leave the structure (rather than waiting until we reach a shallow stop) so that the boat crew can follow us as we drift during deco. Of course it's always a good idea to carry other signalling devices beyond an SMB in case you get separated from the boat.
  - mynameisvlad 4y ago
    I think the only time I've ever seen SMBs used outside of the safety stop are drift dives. And even then, it's been the exception rather than the norm. It's pretty easy to get tangled up if you're doing anything but a single direction drift dive where you're both away from structures and moving in a continuous straight line that doesn't cross itself.