Dive computer necessary?

[Belmont]

Another time I thought we were all pretty much doing the same dive but low and behold three members of the group (including the DM) ended up getting locked out by their computers and had to sit out the next days dives.

With my bottom timer (showing average depth) and tables I don't risk being locked out of the next day's dive.

Also, my Scubapro bottom timer is sealed, no O-ring, and has a battery good for 7 to 10 years.

After 500 dives I still don't see the need for a computer.

Aren't computer dives "trust it dives"?

 

[dmoore19]

Computers use the same theories and calculations as tables for NDLs. If using a computer is a trust "it" dive then diving tables must be a trust "them" dive, the same thing.

 

[Belmont]

With tables it's your brain doing the computing and the interpretation of those theories. If you use your brain and judgment it's not a "trust" them dive.

 

[diverrex]

With tables it's your brain doing the computing and the interpretation of those theories. If you use your brain and judgment it's not a "trust" them dive.

So you're doing every calculation with your brain from scratch?

 

[Belmont]

I prepare a dive plan and I dive it.

I also carry a wet notes booklet and submersible tables for use underwater in case of an unforeseen change in the dive plan.

That type of situation happened a few times and it took me less than a minute to adjust it.

 

[D_B]

no, but here's the drawback - if you are diving without a computer, then you are diving with tables. tables assume a square profile, which means that if you really drop down to 80 feet to see a wreck then spiral up a coral wall slowly for the rest of the dive - so you spent less then 5 minutes at 80 - by tables, the whole dive counts as 80ft. i know you know that from class, but might not be sure what it means. it means that if your first dive is 30 minutes, then your second dive to the same place an hour and 15 minutes later will be 7 minutes...*and that's the maximum*.

you can't dive using someone else's computer because they aren't diving your dive. you are. and your dive is by tables, every time that day or that trip. when the tables say you are done, then you're done, even if others are going for their fourth or more dive of the day. is it a penalty? sort of. but that's the choice you make. the whole point is keeping track of your nitrogen load, and you are using tables.

if this is acceptable, if you have the discipline to perhaps cut the first dive short to save some time for other dives, or if you're only doing one dive a day, then wonderful. problem solved. but me, unless i'm doing one really big dive a day, i'll be using a computer.

if you plan on tables, double check with the op. around here, they want you to have a computer *or* a bottom timer, but are fine either way.

if you are totally aware of all this, please don't take offense. consider it a note to others with the same question who don't have your experience.

This

If your planned dive is to a single planned depth, tables will allow all the NDL time your allowed ... change the depth, several times, or over the entire dive like a shore dive , a computer is going to allow much more NDL time

 

[vladimir]

.....

 

[beaverdivers]

I prepare a dive plan and I dive it.

I also carry a wet notes booklet and submersible tables for use underwater in case of an unforeseen change in the dive plan.

That type of situation happened a few times and it took me less than a minute to adjust it.

You plan a dive to 100' for 19 minutes. At 17 minutes in the dive you are at 71'. A manta ray shows up. I am able to get excellent video of you messing w/ your wet notes and tables. As the manta ray goes to 81' you are further engaged with your tables, as you head up. Then after all the table divers are gone a squadron of 20 eagle rays flys by in perfect formation at 61'. At 51', a school of 200 hundred hammeheads swim by, then a sailfish cruises over head to ckeck me out. At 41'. a male sea lion leaves an oil slick of dung. The dive ends with a huge green turtle.

I get out of the water after an amazing 70+ minute dive.

The table divers have been out of water the for 45 mintutes, sun burned and seasick.

One question I have for someone still using the dive tables " Have you ever heard of this new technology called email or the internet? "

BTW, you will need a computer to play.

The live-aboard that I was on last month required that everyone had at least one dive computer. I believe most divers were using two computers for redundancy.

 

[Belmont]

You plan a dive to 100' for 19 minutes. At 17 minutes in the dive you are at 71'. A manta ray shows up. I am able to get excellent video of you messing w/ your wet notes and tables. As the manta ray goes to 81' you are further engaged with your tables, as you head up. Then after all the table divers are gone a squadron of 20 eagle rays flys by in perfect formation at 61'. At 51', a school of 200 hundred hammeheads swim by, then a sailfish cruises over head to ckeck me out. At 41'. a male sea lion leaves an oil slick of dung. The dive ends with a huge green turtle.

I get out of the water after an amazing 70+ minute dive.

The table divers have been out of water the for 45 mintutes, sun burned and seasick.

One question I have for someone still using the dive tables " Have you ever heard of this new technology called email or the internet? "

BTW, you will need a computer to play.

The live-aboard that I was on last month required that everyone had at least one dive computer. I believe most divers were using two computers for redundancy.

I owned an Apple II in 1976.

Nice caricature.

Remember, I wear a bottom timer that gives me my average depth. I have my NDL in my memory from my dive plan.

The only reason I need to pull my tables is if I exceed my planned time and depth. At a glance I can recalculate my deco if needed (that would happen at the end of the dive anyway) and come out clean as a whistle.

This way I would not end up locked out of diving the next day and miss the rays, hammerhead sharks and mermaid
and have to stay on the boat seasick and sunburned.

 

[peterbj7]

How do you plan a dive in an area you haven't been to before? I'm thinking of a reef dive, NOT a wreck dive with a largely square profile.