Is a Computer essential kit?

[boulderjohn]

I'm pretty sure there were none capable of running Buhlmann GF, VPM, or the full iterative RGBM. As far as I recall, the first was the Liquivision X-1, introduced around 2008.

Really reaching back in my memory on this. I had a USD M1 in 1990 ($400!) and I want to say it was on the Haldane Algorithm? I could be mistaken though

Buhlmann with GFs, VPM, and RGBM were not available in 1990.

The primary usage for those algorithms was technical diving, and the original question in this thread was about very shallow recreational diving, so shallow, in fact, that the use of tables is not really necessary.

My original tech training was DIR, and computers were absolutely not allowed, whether for shallower training diver or decompression diving. When I did my trimix with TDI, everyone was following V-Planner schedules (VPM), determined the day before the dive on a desktop computer. No one used a computer in the water. Then people went to desktop plans with dive computers (mostly Liquivision) as a backup. Then they followed the dive computer with the desktop plan as a backup. Now it has been years since I have seen a technical diver with anything other than 2 Shearwaters.

 

[Gareth J]

Buhlmann with GFs, VPM, and RGBM were not available in 1990.

The primary usage for those algorithms was technical diving, and the original question in this thread was about very shallow recreational diving, so shallow, in fact, that the use of tables is not really necessary.

My original tech training was DIR, and computers were absolutely not allowed, whether for shallower training divers or decompression diving. When I did my trimix with TDI, everyone was following V-Planner schedules (VPM), determined the day before the dive on a desktop computer. No one used a computer in the water. Then people went to desktop plans with dive computers (mostly Liquivision) as a backup. Then they followed the dive computer with the desktop plan as a backup. Now it has been years since I have seen a technical diver with anything other than 2 Shearwaters.

Interesting the evolving way we dived.

This side of the pond, we where using pro planner - which was a DOS based program. Then VR3's came on stream and became very popular very fast. Although we all still carried hard tables, especially with the risk of the warning 'revert to table' appearing (although it did try to give you a best fix).
I still liked pro planner, even when some of the other packages came on line. Although pro planner was clunky to use, I had confidence in it.

There was an American computer that did appear, but had limited traction. I can't honestly remember the name or manufacturer, it could be Liquivision. I seem to remember the Nitrox version was lime green, although its possible my memory is playing tricks on me.

 

[tridacna]

There was an American computer that did appear, but had limited traction. I can't honestly remember the name or manufacturer, it could be Liquivision. I seem to remember the Nitrox version was lime green, although its possible my memory is playing tricks on me.

You thinking of Cochran?

 

[Gareth J]

You thinking of Cochran?

Yay - that's right, it's been bugging me for the last hour or so.

 

[arew+4]

Then, in 1983, Orca Industries introduced the Edge, and multilevel diving and dive computers were in. I jumped on the bandwagon immediately. Sure, the unit had a few weak links: the battery compartment flooded too often and it ate 9-volt batteries the way a kid eats candy, but it was easy to use, and the increased bottom time made the $675 price tag look reasonable. Hell, it was more than reasonable: it was wonderful. It changed diving.

Within a few years of the Edge’s introduction, technological developments and a multitude of other manufacturers reduced dive computers’ size from the Edge’s hefty 1.6 pounds down to wrist models and console inserts. The reduction prompted some sardonic postings on online scuba groups suggesting “One Hundred Things to Do with the Brick (Edge).”

From Undercurrent July 1999

 

[TMHeimer]

Aside from air capacity a diver can almost always get more diving time with a PDC than without one, if changing depth is possible during the dive. At the same depth for the duration of the dive then there isn't a big difference; for a dive like that using a single tank my only use for a PDC would be as depth gauge and thermometer.

Does any of this sound essential?

How true. Almost all of the charter dives I've done (mostly Gulf of Mexico) were going down the anchor line, swimming around a wreck near the bottom, ascending. A DC would be very useful if doing a TRUELY multi-level dive, like to the bottom first for 8 minutes, then 10 mins. at 70', then 20 mins. at 40'. And if it were exact like that, one may even find a use for the old eRDPml.....

 

[Gareth J]

How true. Almost all of the charter dives I've done (mostly Gulf of Mexico) were going down the anchor line, swimming around a wreck near the bottom, ascending. A DC would be very useful if doing a TRUELY multi-level dive, like to the bottom first for 8 minutes, then 10 mins. at 70', then 20 mins. at 40'. And if it were exact like that, one may even find a use for the old eRDPml.....

You'd like the Scapa Wrecks (Light Cruisers).
Down the shot, onto the side of the hull, over the hull, down the superstructure side to the sea bed.

Bit of a mooch along looking at the sea bed wreckage, and under the wreck. Half an eye on the computer, then up a few meters and carry on going (or double back on yourself and zig zag). Working your way up the wreck, managing the deco as you go. There's a lot of wreck to ascend on.

If you're doing scenic's much the same process.

It's when your diving three steel plates on the seabed and a boiler that it doesn't much work.

 

[Celt]

How true. Almost all of the charter dives I've done (mostly Gulf of Mexico) were going down the anchor line, swimming around a wreck near the bottom, ascending. A DC would be very useful if doing a TRUELY multi-level dive, like to the bottom first for 8 minutes, then 10 mins. at 70', then 20 mins. at 40'. And if it were exact like that, one may even find a use for the old eRDPml.....

I made the same dive every day for 3 months to a wreck the mound of brass bars was so big. Dive, dig and fill the cradle. Back up and sit on the deco station. It was some sight when you go down after setting of a blast and they’d shine like gold. A watch was all that was needed.

 

[MichaelMc]

I made the same dive every day for 3 months to a wreck the mound of brass bars was so big. Dive, dig and fill the cradle. Back up and sit on the deco station. It was some sight when you go down after setting of a blast and they’d shine like gold. A watch was all that was needed.

Is your argument that lack of a computer never prevents any dive as people can just use their own boat?

That is what I get from your several posts here.

So lack of a few hundred dollar tool can be solved by having a few tens of thousand dollar tool? Or am I missing something in your argument?

 

[OTF]

a computer is absolutely essential kit, how else would you access scubaboard??