What made you choose your computer algorithm? Experience? Internet? Price? etc

[Fldvr]

I'm using GF also. Since using a computer was verboten in my past lifeI did start with 30/70 to start. After many years of tweaking and then finally after Peter Sotis's presentation I finally woke up to the fact that even the experts can't prove any specific algorithms within the normal ranges we dive in. So for me it's 80/90 and very little penalty for helium.

This works out great for me but some of my buddy's get a little tweaked and scale it back a bit. Lots more to consider here than one size fits all.

Henry

 

[TxNinja]

For me, originally personal reading and research into the models, then practical experience using them OC and CCR. I use VPM/B. Varying the conservatism according to the dive. Buhlman works, but produces a workable profile for the wrong reasons, or at least incomplete reasons. Bubble models are an offshoot of vpm and have been made overly conservative in most applications, of course s'to isn't really a bubble model. Again I think they are incomplete. Using GF on vpm is like doing precise calculations and then averaging the results for the last sum. So it's vpm/b for me, vpm/be I'd only use sub 120 ish and that's not a mainstream part of my diving!

 

[Fldvr]

And the reason I chose GF was to be able to have more control on the stop and entry points into Deco and time spent at those points.

 

[Baron015]

Started using VPMB originally because we were using tables not computer and I liked the VPlanner software on Mac and iPhone.

Switched to Buhlmann with GFs because I got a CCR which came with it.

 

[MeRodent]

Bubble models are an offshoot of vpm and have been made overly conservative in most applications, of course s'to isn't really a bubble model.

My understanding is that VPM is one of a number of bubble models, not that bubble models are an offshoot of VPM.

 

[Captain Starfish]

I started on hire computers running RGBM, no-deco limits were stupidly short and there was insane punishment if you blew the ascent rate or safety stop, etc, etc. So right there I decided RGBM was not for me because it was over-conservative.

My first computer came with ZHL-16 (dunno which flavour) and it was a lot more aggressive and happy times. Until I got bent.

My next computer was a Suunto again but this time I was only using it as a bottom timer against manual charts. I got excited about VGM and used that on a planner but all the guys I was diving with were using ZHL-16 so I switched back so we could compare plans and have it make sense.

After some recent threads around the net regarding deep stops and the way they were handled by the champion of one of the more popular bubble models I have to say, unfortunately, that any faith in the programmer behind that model has been eroded and the model itself, by association, has lost all appeal to me.

So for a few reasons I stick to Buhlmann with gradient factors:
1. It's the same science that I got hammered with during my DM and instructor training, I have a good gut feel for how the model works.
2. The gradient factors, similarly, make sense in how they work. The whole thing has a feel of transparency of how changing settings affects the way the model is working. I like that.
3. The maths is simple and easy to visualise.
Try as I might, I struggle to get that ease and comfort with the bubble models.
4. Most or all of the tech computers I'd ever consider buying have it pretty much as standard and usually free.
5. All my buddies are using it - so comparisons of plans work nicely.
6. Many of the cheapo computers use it too.
7. I get the feeling that it's by far and away the most dived model with the biggest test pool out there. We know it's good and that it works. We have a feel for how far you can push the GFs without getting bit.

Michael, choosing which model to sling into your controller?

 

[TxNinja]

My understanding is that VPM is one of a number of bubble models, not that bubble models are an offshoot of VPM.

Not really, vpm was the instigator and includes bubble modelling (size, surface tension etc by compartment) in its approach, but also includes tissue saturation and total gas volume.

 

[TxNinja]

Suunto, other that the Dx below 40m is not really RGBM it's suunto RGBM. Behaves a lot like buhlman 20/80

 

[MDiedrich]

I use two X1 computers, have set both to conservatism +2, after a deep dive in France (100m) the team around JP Imbert dedicated a few bubbles in my heart. After then i set the x1 to conservatism +3....( i don`t have a PFO!!!)

 

[Michael Thornton]

I haven't seen much in this thread or any of the other threads about the VGM algorithm the later VR computers were using. Why did this algorithm never catch on. What advantages do you guys think GF has over VGM where you have 3 variable settings instead of 2? Is it just because VR went away? Why is no one else attempting a VGM style algorithm?

 

[jptaylor9]

I haven't seen much in this thread or any of the other threads about the VGM algorithm the later VR computers were using. Why did this algorithm never catch on. What advantages do you guys think GF has over VGM where you have 3 variable settings instead of 2? Is it just because VR went away? Why is no one else attempting a VGM style algorithm?

VR's wasn't a proper implementation, therefore most stuck with their original algorithm.

The problem with VPM is it takes more processor power to run the algorithm, most CPU's used in typical dive computers don't have enough poke....

 

[Hanssing]

Went form VPM-B to GF

Disclaimer - I consider myself to have a predisposition to DCS (wristpain, niggles and skinbends), and accordingly I dive very conservative.

I originally used an Apeks Quantum, which used some sort of Buhlman 12 model - Got slightly bent on single tank 15l OC dives on some occasions (multiple dives, cold water, overweight, etc).

I then switched to CCR.

I had X1 as soon as it was released. I love the V-planner live on it.
But I still get bent using it even with the model set to VPM-BE+5, using direct ascent.

I am now using Shearwater Predator, with GF 25/70 with success. I just did 15 dives in Norway, and since I still dive with my X1 I know that GF25/70 is way more conservative than VPMB+5.
During a Tx18/45 dive to the wreck 'D/S Consul Carl Fisser' for app. 55mins bottom-time between 25-50m the X1 cleared after 20min, and the GF cleared after 30min.
Thats 50% more than the X1....

In summary I switched from VPM since the X1 implementation at maximum conservatism still gave me DCS-symptoms :dizzy:
But I am still running deep-stops as GFLow is 25.

I want my algoritm set so I am confident that I have decoed out cleanly - not at the edge of DCS. And currently due to changes other than algortim alone, it seems I am there
But thats not with VPM.

Hanssing