Posted by Chuck Tribolet on February 21, 2005 at 22:27:17:
In Reply to: you just cannot trust dive computer posted by northcoast diver on February 21, 2005 at 21:33:41:
If dive computers were highly untrustworthy, we'd
be bending recreational divers left and right, and
we're not. When dive computers fail, they usually
fail in an obvious manner, like not working at all
(typ. dead battery), or giving a completely wonky
reading (I had one tell me I was at 255 feet,
ox-toxed, and bent). Given I was at the bottom of
the deepest macrocystis which only grows to about
70', and that Phil had said that the anchor was in
70', and that my other computer said I was at 70',
I knew the computer was busted. And in a
recreational profile, if the computer breaks, you
abort the dive, or in my case, use the backup
computer. No big deal, there's always tomorrow.
I'm perfectly capable working this stuff in my
head, and I play a little head game guessing at
what the computer is going to say, and I'm usually
real close. I trust that if the computer is
giving me a reasonable answer, it's giving me
an accurate answer, or at least as accurate as
its algorithms.
And yesterday we had a great example of why your
idea to limit the size of the bottle is silly.
There was a rather ripping current at Ball Buster.
Surface currents aren't uncommon there, but this
one went top to bottom. Linda and I were kicking
like crazy the whole dive, and we had a 40 minute
aerobic workout. Obviously, the gas consumption
was higher, but with the larger tanks, we still
had a full length dive. And it was worth it --
we had a Giant Pacific Octopus. I've seen a
couple before in Monterey, but this one was huge.
Its biggest suckers were the size of the top of
a Coke can.
Once again: a one hour surface interval doesn't
work for me. It's not enough time to stow the
gear, pull the hook, go whale or dolphin watching,
have lunch, decide where to go, drop the hook, and
gear up. Today's surface interval was 1:55. And
I typically don't do more than two dives,
occasionally three, so I don't care about doing
little short dives all day.
You act as if that dive to 175' requiring a safety
stop is unusual. ALL dives require safety stops.
But there aren't any in your best mix profiles.
Given that I haven't gotten bent in 1400 dives,
and that you've gotten bent at least once, and
I've heard reports of a second time, in a lot less
dives than that, I'll follow my own counsel, and
not yours.
Chuck