Tec Computers?

[PerroneFord]

DrBill,

If the occasion should ever strike, I think you'd be a prime candidate for learning about ratio deco and depth averaging. Beyond that, your scenario sounds very much like something I do, though at shallower depths. I have wetnotes that indicate deco plans. Basically, it's a page for every 20ft so there's an 80ft page, a 100ft, a 120, etc. On each page there is a table for bottom time over NDL in 5 minute increments. So if NDL for 80ft was say 45 minutes, I'd have an 80ft page with 50, 55, 60, 65, and 70 minutes on it. Then on the chart it would say what stops need to be made and for how long.

This is a conservative way of doing things, but I wanted something in case my computer broke. You could have something like this down to 200ft just in case you ran into real trouble, and needed an emergency bailout plan.

I've done this for EAN32, but will soon do something similar for other gases and for when I am carrying O2 or EAN50 as deco gas. You could do something more coarse like every 40ft and every 10 minutes, and put it all on one page. Then just select the plan that is closest to what you dove, on the competitive side. Such as you did a 150ft dive for 32 minuts, you'd select the 180ft plan for 40 minutes...

 

[rjack321]

I do frequent dives in the 150-200 ft range using my Uwatec Aladin Pro dive computer. However, I don't rely 100% on the deco obligation it indicates. I generally double or triple it, which is easy since the offshore slopes allow me to spend a lot of time in shallow water (20-50 ft) as I ascend.

Although many of the dives I do would be considered technical in some senses of the word, I am not able to plan my dives the same way most technical divers do. I am not diving sites with known bottom depths (such as wrecks). I dive to take video footage, and stop wherever I find something interesting within the depth range I go. For that reason the computer is pretty essential, a backup very helpful. I pretty much know the profiles I can dive, so as long as I have a backup depth gauge and bottom timer I can recover without much trouble even if the computer fails (as it has).

So how do you know if you've got the deco gas? What happens if you lost a deco gas?

I preplan my deco dive gas use within a general ~40ft depth range. Mostly I trade depth for time or vice versa with ratio deco (DOTF) once in the water.

 

[karstdvr]

I didn't either in the past...... but man is life easier with a computer.....

Don't get me wrong, GUE training is superb, but everything is just so much easier when a computer keeps track of actual profiles, especially in caves

I agree 100%!!!

I know how to use tables,bottom timer etc etc but a computer in my opinion is the best thing for scuba diving since the demand valve regulator. It is funny when talking with some cave divers who have been around for 30 years,and they marvel at the equipment advances that have occured,but think it is so funny that we want to go backwards and give up the dive computer for their old technology of the tables/depth guage/bottom timer.

Not to poke fun,but the other thing that is about useless in cave diving is the wrist mounted compass. I know some are required to wear it,but ironically it sits there unused because the is the least useful form on navigation in a cave.

 

[PerroneFord]

Not to poke fun,but the other thing that is about useless in cave diving is the wrist mounted compass. I know some are required to wear it,but ironically it sits there unused because the is the least useful form on navigation in a cave.

So when are we going diving? I need to check out Madison...

 

[rjack321]

Not to poke fun,but the other thing that is about useless in cave diving is the wrist mounted compass. I know some are required to wear it,but ironically it sits there unused because the is the least useful form on navigation in a cave.

I used my compass on about 1/2 of my Cave1 training dives. Chris LM gave us general headings on where to find the mainline. Super helpful.

I tend to remember turns by left right not compass headings. So I agree unless you have some insider knowledge like we were given its not super useful.

 

[karstdvr]

I used my compass on about 1/2 of my Cave1 training dives. Chris LM gave us general headings on where to find the mainline. Super helpful.

I tend to remember turns by left right not compass headings. So I agree unless you have some insider knowledge like we were given its not super useful.

Caves change shape and direction so much that unless you have a long linear trunk passage that doesn't deviate in heading I find a compass useless. I do a lot of surveying,and even with my survey data in my hands I find my compass about useless. I say it is good that you get the experience because compass use is a dying art,even most cave divers have never had exposure to surveying techniques. Actually the best technique to learn navigation is through progessive penetration and learning the caves.

 

[karstdvr]

So when are we going diving? I need to check out Madison...

Unfortunately I will be in your backyard guiding a dive.

 

[PerroneFord]

Emerald or Indian?

 

[karstdvr]

Emerald or Indian?

Indian

Will Greg be open Saturday for gas fills?

 

[PerroneFord]

He said he was not going anywhere this weekend. I'll verify for you and get back to you.

(what do you need? I can have him boost Friday)