Compass issues
- Thread starter bc214
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freeclimbmtb
Contributor
I seem to remember my compass having a small air bubble in it...keep that centered on the compass face and you know it's level...
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Sent from my iPhone using Tapatalk
I may be wrong here and if so please don't tell my wife.
But I have always considered the bubble (if present) to be a tolerable manufacturing defect. I don't think the lens is domed to make the bubble's position indicate anything. If you can center the bubble them it probably is level and you have more patience than I do.Pete
I concur. If you are serious about underwater navigation you cant beat a swim board with a good compass. What makes a good compass? Generally a large diameter in a spherical housing is more sensitive, accurate, and less influenced by being out of level. I have a friend who is a retired SEAL who uses one of these and can hit the target on a two mile underwater swim but I think theres more to it than just the compass.
RJE International - Diver Navigation
We used SK7s for years, but I have given up on them. The plastic of the case simply isn't durable, and eventually, they all leak and have to be replaced. We're using the Uwatech compasses now, which look quite similar to the OP's. You do have to be very careful to hold them level.
It's my opinion, in general, that you can't hope for the kind of accuracy the OP wants, when navigating with an underwater compass. Plus or minus 15 is pretty typical accuracy; I usually try to head for something sufficiently large that I'm not going to miss it with that, and I also incorporate as much natural navigation information (depth contours, topography, sometimes even specific animals!) as I can.
It's my opinion, in general, that you can't hope for the kind of accuracy the OP wants, when navigating with an underwater compass. Plus or minus 15 is pretty typical accuracy; I usually try to head for something sufficiently large that I'm not going to miss it with that, and I also incorporate as much natural navigation information (depth contours, topography, sometimes even specific animals!) as I can.
AfterDark
Contributor
Current alone could throw one off that much, 15 deg. As a tadpole I practiced UW NAV in a fresh water lake using both snorkel (being able to "cheat" helps the learning process in this case) and with scuba. The kind of accuracy the OP is looking for was quite do able in the lake. I've never been able to duplicate that in the ocean. The 1st compass I had did indeed have a bubble that when at the top in the dome indicated the compass was level, said so right in the instructions.
Most problems using a compass originate in the user staring at it while swimming. Just point your compass to a point as far away as possible and swim to it. Repeat. It's that easy.
If you stare at your compass, you will veer off in one direction.
If you stare at your compass, you will veer off in one direction.
AfterDark
Contributor
Staring at the compass and don't see it move when veering off course? How does that work? I usually hold a course say 180 deg and watch ?stare? at it to make sure I don't veer off course. I'm in less than 10' vis most dives so pointing like on land doesn't work here, the OP will be doing his NAV dives in RI.
A compass needle does not need to move for you to veer off.
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