Multi deco vs V-planner vs GUE Deco Planner

[Wibble]

Ok, maybe I'm stirring the wasp nest with a stick once again, but just for argument sake, have a look at the 2 run times on the enclosed document, doesn't the VPM one looks a lot like the Buhlmann + GF ?

Absolutely. The difference is that Buhlmann's far more standardised across the devices and if you're diving with someone else -- or a different backup computer -- it's so much more convenient that they match each other.

Bloody Suunto Tax where you *must* stay down for another 5 or 10 minutes past clearing deco lest you brick the thing.

 

[Wibble]

The software to install VPlanner or MultiDeco onto an X1? I don't think so. MultiDeco has always worked for me, both the IOS and MacOS versions.

By X1, do you mean a new-fangled M1 CPU, or is that a PowaPC from 2007?

(It should work on an M1 through Rosetta -- don't have an M1 so can't tell you. It does work on several of my Intel MacBook Pros)

 

[tbone1004]

Ok, maybe I'm stirring the wasp nest with a stick once again, but just for argument sake, have a look at the 2 run times on the enclosed document, doesn't the VPM one looks a lot like the Buhlmann + GF ?

on individual dives you can massage the GF's to correspond roughly to VPM. The issue is that VPM+2 is being compared to 35/85 and current researchers are saying that 50/70 is showing less signs of decompression stress and is what they are personally diving. 35/85 is going to show a LOT more considering the shape of that ascent curve and the total amount of decompression. If it matched something like 50/80 or 60/80 or even somewhere remotely close to that then there would be some room for discussion but the profiles drop the GF-lo and have very aggressive GF-hi's and that is where the issues arise.

 

[kensuf]

By X1, do you mean a new-fangled M1 CPU, or is that a PowaPC from 2007?

(It should work on an M1 through Rosetta -- don't have an M1 so can't tell you. It does work on several of my Intel MacBook Pros)

I can confirm multideco works on an M1 mac.

 

[rongoodman]

By X1, do you mean a new-fangled M1 CPU, or is that a PowaPC from 2007?

(It should work on an M1 through Rosetta -- don't have an M1 so can't tell you. It does work on several of my Intel MacBook Pros)

No, I was referring to the Liquivison X1 dive computer, introduced around 2008. I don't remember much about the supplied software, but you could buy a copy of VPlanner(MultiDeco came later) to install on it. The tool required to do that install was a Windows .exe file, in spite of much whining to Ross on the part of us Mac users. It was discontinued in 2013 and Liquivision was later bought out by Huish and disappeared. The X1 was in some ways ahead of its time, with an OLED display (bright enough to follow a cave line), tap interface, and the power to run VPM-B or Buhlmann GF. One of their later models, the Xeo I think, had a full implementation of RGBM available from a third party vendor. There's a nice review of the X1 by TS&M floating around here someplace.

 

[boulderjohn]

No, I was referring to the Liquivison X1 dive computer, introduced around 2008. I don't remember much about the supplied software, but you could buy a copy of VPlanner(MultiDeco came later) to install on it. The tool required to do that install was a Windows exec file, in spite of much whining to Ross on the part of us Mac users. It was discontinued in 2013 and Liquivision was later bought out by Huish and disappeared. The X1 was in some ways ahead of its time, with an OLED display (bright enough to follow a cave line), tap interface, and the power to run VPM-B or Buhlmann GF. One of their later models, the Xeo I think, had a full implementation of RGBM available from a third party vendor. There's a nice review of the X1 by TS&M floating around here someplace.

The VPM version that ran on the Liquivision was called V-Planner Live and was created by Ross Hemingway. Ross is also the author of V-Planner and Multi-deco, but they are different programs.

V-Planner Live VPM-B, VPM-B/E dive deco computer firmware

www.hhssoftware.com

 

[boulderjohn]

Which is why I qualified with "as in". I am told Suunto DM will let you plan a deco dive for Zoop so they support that kind of "recreational". I don't believe there is a deco planner from my Cressi so it doesn't.

I am not sure I understand what you wrote, so forgive me if I misunderstood. As far as I know, all "recreational" dive computers say that they are not supposed to be used for deco diving, but they will guide you through a deco sequence if you violate NDLs, intentionally or not. Many years ago, long before I had any tech training, I dived the San Francisco Maru in Truk Lagoon (181 feet max) and followed my Suunto Cobra in doing so.

 

[JMBL]

on individual dives you can massage the GF's to correspond roughly to VPM. The issue is that VPM+2 is being compared to 35/85 and current researchers are saying that 50/70 is showing less signs of decompression stress and is what they are personally diving. 35/85 is going to show a LOT more considering the shape of that ascent curve and the total amount of decompression. If it matched something like 50/80 or 60/80 or even somewhere remotely close to that then there would be some room for discussion but the profiles drop the GF-lo and have very aggressive GF-hi's and that is where the issues arise.

Agreed, but the run times I gave here, were used some years back, and the position on GF settings was a bit different by then.

A question still, (and I DO mean just that, so please, don't beat on my head) : you say 85 is very aggressive. Could you elaborate, please ? From what I remember, 85/85, is a recommended setting while diving on air, especially while diving Rec. So according to you : is GF hi 85 aggressive per se, or just in the case of a Trimix dive (Helium and N2 off gasing behaviour are different) ?

 

[scubadada]

Hi @boulderjohn

I may be wrong but interpreted what @dmaziuk wrote as most recreational computers do not supply a deco planner, so that you can plan a deco dive ahead of time using their chosen deco algorithm. I have heard that the Suunto application may be an exception but have no personal experience with it.

Most recreational computers have an NDL planner, but no deco planner. As you said, they will guide you to a safe ascent from a deco obligation, planned or unplanned.

 

[boulderjohn]

A question still, (and I DO mean just that, so please, don't beat on my head) : you say 85 is very aggressive. Could you elaborate, please ? From what I remember, 85/85, is a recommended setting while diving on air, especially while diving Rec. So according to you : is GF hi 85 aggressive per se, or just in the case of a Trimix dive (Helium and N2 off gasing behaviour are different) ?

I think people have different attitudes about this with respect to deco dives and NDL dives. That includes me.

When I do deco dives, use either 70 or 75, depending upon what the others in my team prefer.

When I do NDL dives, I usually use 85, maybe even 90, but that is really something of a deception. Dive boat operators usually insist that you stay within NDLs. If you use something like 75 or 70 and follow those rules, you will have very short dives. So what I do is follow the 85 NDLs and then hang out at the safety stop level until my SurfGF goes below 70. Everyone else is using their 3 or 5 minute safety stop countdown and don't realize I am doing something different.

I used to be a touch more honest about what I was doing. I used to use the same GFs for tech and NDL diving, ignoring the fact that I went into deco on NDL dives earlier than I would if I took a few seconds to change my GFs. Then I made the mistake of writing that on ScubaBoard. I wrote that I went briefly into deco briefly on NDL dives, knowing I would not be in deco if I changed the GFs.

A guy who had taken to hating me for some reason (he seemed to live for the opportunity to attack me) took advantage of that opportunity. Rather than respond in that thread, he started a new thread (so I would not see it for a while and so he could frame the issue his way) in which he misrepresented what I wrote and said I was violating SB norms by advocating unsafe practices by advising divers to ignore NDLs and do deco dives without proper gear or training. It took me 3 days to realize the thread was running, and when I did I found people were so outraged that they were calling for me to be punished for this transgression. I corrected the misinformation on about the 5th page of that thread, but the damage was done, and my reputation was sullied for quite some time.

So I play it safe. I change the GFs to make it more compatible with what other people are doing on the off chance that some dimwit might see that I have gone into deco and go similarly ballistic.