VR3 BUH or VPM

Serge · 11th April 2008, 03:29

Quote: (Originally Posted by tecdivertraining)

That doesn't make sense by staying at your last stop to clear some of the Buh time remaining, which is what I think lance is saying he would be on-gassing inerts?

What I inferred from Lance's post was that he's planning to follow VPM on deep stops, and complete the other half of deco on Buhlmann; that did not not make sense. If all he's trying to do is clear his computers, that's another issue.

tecdivertraining · 11th April 2008, 03:30

It seems to me theirs quite a few getting these X1 computers and using VPMB live, so what I would like to know is on what big dives has it been used and followed sub 150m

as anything thats a complete rewrite makes me shiver at what funky business it could do on a long deep dive.

I feel confident that the vr3 has been used and followed on many successful sub 150m dives.

"V-Planner Live is a full decompression firmware program that uses genuine VPM-B and VPM-B/E for its decompression calculations. This "Live" version is a complete rewrite of the VPM algorithms to perform continuous underwater decompression calculations. V-Planner Live computes the ascent every few seconds, starting with regular NDL limits, and progressing into the decompression limits".

diverklondike · 11th April 2008, 03:31

Quote: (Originally Posted by Meng_Tze)

X1 was +2 and VR3 was 0

Were you running VPM B or VPM B/E at +2 on the X1

tecdivertraining · 11th April 2008, 03:34

Quote: (Originally Posted by Serge)

What I inferred from Lance's post was that he's planning to follow VPM on deep stops, and complete the other half of deco on Buhlmann; that did not not make sense. If all he's trying to do is clear his computers, that's another issue.

That would need lance to confirm but I'm sure thats all he is planning to do just a little padding.

Drmike · 11th April 2008, 03:44

Quote: (Originally Posted by Meng_Tze)

For my frame of reference, what would you consider a big dive and what would be a small or medium dive?

I mean big in terms of deco time.

Im often doing dives where the difference in deco between models can be several hours.

Take a 100m dive for say 40mins. Difference in deco time between models is around 2+hours!

For dives down to 50m for say 40mins the difference (VR3VPM, VR3BUH, VPMBE) isnt really much, but deeper and longer it can be significant

Drmike · 11th April 2008, 03:56

Quote: (Originally Posted by Serge)

What I inferred from Lance's post was that he's planning to follow VPM on deep stops, and complete the other half of deco on Buhlmann; that did not not make sense. If all he's trying to do is clear his computers, that's another issue.

in practice (on dives of reasonable size) the two different VR3 algos give very similar deco other than the few (and longer) deep stops vr3buh start deeper and spread over longer. The middle deco is practically identical and then only the tail end (last few stops) are longer on VR3BUH

So yes he will be ongassing a tad more at depth but in practice the vr3buh algo ends up catching up with the vr3vpm algo on most dives shortly after last pyle -esq deep stop so difference isnt much. Then matches all the way up untill you get to the shallow stops where buh is longer (by matching I mean not significantly different)

usually on dives down to say 50m ish the two computers are only a few mins apart after deep stops.

The main sign. difference in stop times comes in the tail - where it can be significant

So I think doing the vr3vpm all the way up to the shallow then finishing with vr3buh is more conservative than sticking to vr3vpm

..but Im not a deco expert - this has worked for me in past

tecdivertraining · 11th April 2008, 04:01

Quote: (Originally Posted by Drmike)

in practice (on dives of reasonable size) the two different VR3 algos give very similar deco other than the few (and longer) deep stops vr3buh start deeper and spread over longer. The middle deco is practically identical and then only the tail end (last few stops) are longer on VR3BUH

So yes he will be ongassing a tad more at depth but in practice the vr3buh algo ends up catching up with the vr3vpm algo on most dives shortly after last pyle -esq deep stop so difference isnt much. Then matches all the way up.

usually on dives down to say 50m ish the two computers are only a few mins apart after deep stops.

On the money it also works for me

The main sign. difference in stop times comes in the tail - where it can be significant

So I think doing the vr3vpm all the way up to the shallow then finishing with vr3buh is more conservative than sticking to either (vr3vpm or vr3buh)

..but Im not a deco expert - this has worked for me in past

On the money, it also works for me. I'm also able to walk up my stairs to bed on my own after the dives.

diverklondike · 11th April 2008, 04:24

Quote: (Originally Posted by Drmike)

in practice (on dives of reasonable size) the two different VR3 algos give very similar deco other than the few (and longer) deep stops vr3buh start deeper and spread over longer. The middle deco is practically identical and then only the tail end (last few stops) are longer on VR3BUH

So yes he will be ongassing a tad more at depth but in practice the vr3buh algo ends up catching up with the vr3vpm algo on most dives shortly after last pyle -esq deep stop so difference isnt much. Then matches all the way up untill you get to the shallow stops where buh is longer (by matching I mean not significantly different)

usually on dives down to say 50m ish the two computers are only a few mins apart after deep stops.

The main sign. difference in stop times comes in the tail - where it can be significant

So I think doing the vr3vpm all the way up to the shallow then finishing with vr3buh is more conservative than sticking to vr3vpm

..but Im not a deco expert - this has worked for me in past

Ok... Just to keep it interesting... Mike... Are you sticking to an "He" based DIL through your entire dive? My personal contention through all of this is that we still don't understand how to properly handle "He". That's a variable that we have not mentioned to this point. It also effects the definition of what is and or is not conservative.

There are number of people that are doing 100m ish dives using GFs of 15/85 or so on something like a 9/60 dil and switching the computer to "Air" as a dil starting at their first deco stop but staying on their high "He" dil. The goal is to reduce what they feel is an inproper handling of "He" in the Buhl. based deco algo.

M

Drmike · 11th April 2008, 05:12

Quote: (Originally Posted by diverklondike)

Ok... Just to keep it interesting... Mike... Are you sticking to an "He" based DIL through your entire dive?

yup

Quote:

My personal contention through all of this is that we still don't understand how to properly handle "He". That's a variable that we have not mentioned to this point. It also effects the definition of what is and or is not conservative.

There are number of people that are doing 100m ish dives using GFs of 15/85 or so on something like a 9/60 dil and switching the computer to "Air" as a dil starting at their first deco stop but staying on their high "He" dil. The goal is to reduce what they feel is an inproper handling of "He" in the Buhl. based deco algo.

M

Doesnt the algo penalise you for He? In which case doesnt switching comp to air infact give you less conservation?

Personaly when we are less certain about something I lean to side of caution rather than other way around, and I really dont see theres that much hurry to get out the water (cave, OW with good conditions)

I havent ever dived with anyone (or heard of anyone) doing air deco off mix on big dives. I assume theres a big effect on deco time. Theres no way Ive got big enough balls to do that without more validation first. Risk V reward is nowhere near good enough for me to try that.

Unless Im in really truly terrible currents and swell in the middle of a shipping lane (so no floating platform) shaving off half hour here or hour there is really not worth it in my opinion if you consider what your risking. A lot of my dives are long 6-10hrs range so in relation taking risk just to save an hour or so is just not something Im comfortable with - id rather just sit there a few hours longer and know with higher level of certainty that im gonna be able to sustain an erection after the dive

Ive dived with a few guys who were always hunting for quick deco. Both of them still dive and dive deep, but both of them have permanent neurodamage sustained on dives we did together where I did signif longer deco than them. That may be a coincidence but it is something I consider when the urge to cut deco time starts to be so strong

graham_hk · 11th April 2008, 05:32

Quote: (Originally Posted by Drmike)

yup

Doesnt the algo penalise you for He? In which case doesnt switching comp to air infact give you less conservation?

Personaly when we are less certain about something I lean to side of caution rather than other way around, and I really dont see theres that much hurry to get out the water (cave, OW with good conditions)

I havent ever dived with anyone (or heard of anyone) doing air deco off mix on big dives. I assume theres a big effect on deco time. Theres no way Ive got big enough balls to do that without more validation first. Risk V reward is nowhere near good enough for me to try that.

Unless Im in really truly terrible currents and swell in the middle of a shipping lane (so no floating platform) shaving off half hour here or hour there is really not worth it in my opinion if you consider what your risking. A lot of my dives are long 6-10hrs range so in relation taking risk just to save an hour or so is just not something Im comfortable with - id rather just sit there a few hours longer and know with higher level of certainty that im gonna be able to sustain an erection after the dive

Ive dived with a few guys who were always hunting for quick deco. Both of them still dive and dive deep, but both of them have permanent neurodamage sustained on dives we did together where I did signif longer deco than them. That may be a coincidence but it is something I consider when the urge to cut deco time starts to be so strong

Mike - are we meeting for that beer/dinner (give me a call or email me 09285031475)

I can introduce you to some good bag handlers you were talking about earlier.

11th April 2008, 03:29	#71 (permalink)
Serge RBW Member Current Rebreather/s: Evolution Other Rebreather/s: Join Date: Dec 2007 Location: NY Posts: 120	Re: VR3 BUH or VPM Quote: (Originally Posted by tecdivertraining) That doesn't make sense by staying at your last stop to clear some of the Buh time remaining, which is what I think lance is saying he would be on-gassing inerts? What I inferred from Lance's post was that he's planning to follow VPM on deep stops, and complete the other half of deco on Buhlmann; that did not not make sense. If all he's trying to do is clear his computers, that's another issue.
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11th April 2008, 03:30	#72 (permalink)
tecdivertraining EXPLORER Current Rebreather/s: Inspiration Classic Inspiration Vision Evolution Megalodon Ouroboros Dolphin Other Rebreather/s: Not Bought Yet Dolphin Join Date: May 2005 Location: Phuket, Thailand Posts: 532	Re: VR3 BUH or VPM It seems to me theirs quite a few getting these X1 computers and using VPMB live, so what I would like to know is on what big dives has it been used and followed sub 150m as anything thats a complete rewrite makes me shiver at what funky business it could do on a long deep dive. I feel confident that the vr3 has been used and followed on many successful sub 150m dives. "V-Planner Live is a full decompression firmware program that uses genuine VPM-B and VPM-B/E for its decompression calculations. This "Live" version is a complete rewrite of the VPM algorithms to perform continuous underwater decompression calculations. V-Planner Live computes the ascent every few seconds, starting with regular NDL limits, and progressing into the decompression limits". __________________ Mathew Partridge Technical Director Pro-Tech Dive College www.protechdivers.com www.tech-ccr.com
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11th April 2008, 03:31	#73 (permalink)
diverklondike RBW Member Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Oct 2005 Location: Delaware, USA Posts: 1,714	Re: VR3 BUH or VPM Quote: (Originally Posted by Meng_Tze) X1 was +2 and VR3 was 0 Were you running VPM B or VPM B/E at +2 on the X1
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11th April 2008, 03:34	#74 (permalink)
tecdivertraining EXPLORER Current Rebreather/s: Inspiration Classic Inspiration Vision Evolution Megalodon Ouroboros Dolphin Other Rebreather/s: Not Bought Yet Dolphin Join Date: May 2005 Location: Phuket, Thailand Posts: 532	Re: VR3 BUH or VPM Quote: (Originally Posted by Serge) What I inferred from Lance's post was that he's planning to follow VPM on deep stops, and complete the other half of deco on Buhlmann; that did not not make sense. If all he's trying to do is clear his computers, that's another issue. That would need lance to confirm but I'm sure thats all he is planning to do just a little padding. __________________ Mathew Partridge Technical Director Pro-Tech Dive College www.protechdivers.com www.tech-ccr.com
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11th April 2008, 03:44	#75 (permalink)
Drmike RBW Member Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,378	Re: VR3 BUH or VPM Quote: (Originally Posted by Meng_Tze) For my frame of reference, what would you consider a big dive and what would be a small or medium dive? I mean big in terms of deco time. Im often doing dives where the difference in deco between models can be several hours. Take a 100m dive for say 40mins. Difference in deco time between models is around 2+hours! For dives down to 50m for say 40mins the difference (VR3VPM, VR3BUH, VPMBE) isnt really much, but deeper and longer it can be significant __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment Last edited by Drmike : 11th April 2008 at 04:02.
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11th April 2008, 03:56	#76 (permalink)
Drmike RBW Member Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,378	Re: VR3 BUH or VPM Quote: (Originally Posted by Serge) What I inferred from Lance's post was that he's planning to follow VPM on deep stops, and complete the other half of deco on Buhlmann; that did not not make sense. If all he's trying to do is clear his computers, that's another issue. in practice (on dives of reasonable size) the two different VR3 algos give very similar deco other than the few (and longer) deep stops vr3buh start deeper and spread over longer. The middle deco is practically identical and then only the tail end (last few stops) are longer on VR3BUH So yes he will be ongassing a tad more at depth but in practice the vr3buh algo ends up catching up with the vr3vpm algo on most dives shortly after last pyle -esq deep stop so difference isnt much. Then matches all the way up untill you get to the shallow stops where buh is longer (by matching I mean not significantly different) usually on dives down to say 50m ish the two computers are only a few mins apart after deep stops. The main sign. difference in stop times comes in the tail - where it can be significant So I think doing the vr3vpm all the way up to the shallow then finishing with vr3buh is more conservative than sticking to vr3vpm ..but Im not a deco expert - this has worked for me in past __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment Last edited by Drmike : 11th April 2008 at 04:01.
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11th April 2008, 04:01	#77 (permalink)
tecdivertraining EXPLORER Current Rebreather/s: Inspiration Classic Inspiration Vision Evolution Megalodon Ouroboros Dolphin Other Rebreather/s: Not Bought Yet Dolphin Join Date: May 2005 Location: Phuket, Thailand Posts: 532	Re: VR3 BUH or VPM Quote: (Originally Posted by Drmike) in practice (on dives of reasonable size) the two different VR3 algos give very similar deco other than the few (and longer) deep stops vr3buh start deeper and spread over longer. The middle deco is practically identical and then only the tail end (last few stops) are longer on VR3BUH So yes he will be ongassing a tad more at depth but in practice the vr3buh algo ends up catching up with the vr3vpm algo on most dives shortly after last pyle -esq deep stop so difference isnt much. Then matches all the way up. usually on dives down to say 50m ish the two computers are only a few mins apart after deep stops. On the money it also works for me The main sign. difference in stop times comes in the tail - where it can be significant So I think doing the vr3vpm all the way up to the shallow then finishing with vr3buh is more conservative than sticking to either (vr3vpm or vr3buh) ..but Im not a deco expert - this has worked for me in past On the money, it also works for me. I'm also able to walk up my stairs to bed on my own after the dives. __________________ Mathew Partridge Technical Director Pro-Tech Dive College www.protechdivers.com www.tech-ccr.com
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11th April 2008, 04:24	#78 (permalink)
diverklondike RBW Member Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Oct 2005 Location: Delaware, USA Posts: 1,714	Re: VR3 BUH or VPM Quote: (Originally Posted by Drmike) in practice (on dives of reasonable size) the two different VR3 algos give very similar deco other than the few (and longer) deep stops vr3buh start deeper and spread over longer. The middle deco is practically identical and then only the tail end (last few stops) are longer on VR3BUH So yes he will be ongassing a tad more at depth but in practice the vr3buh algo ends up catching up with the vr3vpm algo on most dives shortly after last pyle -esq deep stop so difference isnt much. Then matches all the way up untill you get to the shallow stops where buh is longer (by matching I mean not significantly different) usually on dives down to say 50m ish the two computers are only a few mins apart after deep stops. The main sign. difference in stop times comes in the tail - where it can be significant So I think doing the vr3vpm all the way up to the shallow then finishing with vr3buh is more conservative than sticking to vr3vpm ..but Im not a deco expert - this has worked for me in past Ok... Just to keep it interesting... Mike... Are you sticking to an "He" based DIL through your entire dive? My personal contention through all of this is that we still don't understand how to properly handle "He". That's a variable that we have not mentioned to this point. It also effects the definition of what is and or is not conservative. There are number of people that are doing 100m ish dives using GFs of 15/85 or so on something like a 9/60 dil and switching the computer to "Air" as a dil starting at their first deco stop but staying on their high "He" dil. The goal is to reduce what they feel is an inproper handling of "He" in the Buhl. based deco algo. M
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11th April 2008, 05:12	#79 (permalink)
Drmike RBW Member Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,378	Re: VR3 BUH or VPM Quote: (Originally Posted by diverklondike) Ok... Just to keep it interesting... Mike... Are you sticking to an "He" based DIL through your entire dive? yup Quote: My personal contention through all of this is that we still don't understand how to properly handle "He". That's a variable that we have not mentioned to this point. It also effects the definition of what is and or is not conservative. There are number of people that are doing 100m ish dives using GFs of 15/85 or so on something like a 9/60 dil and switching the computer to "Air" as a dil starting at their first deco stop but staying on their high "He" dil. The goal is to reduce what they feel is an inproper handling of "He" in the Buhl. based deco algo. M Doesnt the algo penalise you for He? In which case doesnt switching comp to air infact give you less conservation? Personaly when we are less certain about something I lean to side of caution rather than other way around, and I really dont see theres that much hurry to get out the water (cave, OW with good conditions) I havent ever dived with anyone (or heard of anyone) doing air deco off mix on big dives. I assume theres a big effect on deco time. Theres no way Ive got big enough balls to do that without more validation first. Risk V reward is nowhere near good enough for me to try that. Unless Im in really truly terrible currents and swell in the middle of a shipping lane (so no floating platform) shaving off half hour here or hour there is really not worth it in my opinion if you consider what your risking. A lot of my dives are long 6-10hrs range so in relation taking risk just to save an hour or so is just not something Im comfortable with - id rather just sit there a few hours longer and know with higher level of certainty that im gonna be able to sustain an erection after the dive Ive dived with a few guys who were always hunting for quick deco. Both of them still dive and dive deep, but both of them have permanent neurodamage sustained on dives we did together where I did signif longer deco than them. That may be a coincidence but it is something I consider when the urge to cut deco time starts to be so strong __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment Last edited by Drmike : 11th April 2008 at 05:23.
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11th April 2008, 05:32	#80 (permalink)
graham_hk Custom Title Allowed! Current Rebreather/s: RB80 / Clone Other Rebreather/s: Inspiration Classic Classic Kiss MK 15.X RB80 / Clone Join Date: Nov 2005 Location: Philippines Posts: 107	Re: VR3 BUH or VPM Quote: (Originally Posted by Drmike) yup Doesnt the algo penalise you for He? In which case doesnt switching comp to air infact give you less conservation? Personaly when we are less certain about something I lean to side of caution rather than other way around, and I really dont see theres that much hurry to get out the water (cave, OW with good conditions) I havent ever dived with anyone (or heard of anyone) doing air deco off mix on big dives. I assume theres a big effect on deco time. Theres no way Ive got big enough balls to do that without more validation first. Risk V reward is nowhere near good enough for me to try that. Unless Im in really truly terrible currents and swell in the middle of a shipping lane (so no floating platform) shaving off half hour here or hour there is really not worth it in my opinion if you consider what your risking. A lot of my dives are long 6-10hrs range so in relation taking risk just to save an hour or so is just not something Im comfortable with - id rather just sit there a few hours longer and know with higher level of certainty that im gonna be able to sustain an erection after the dive Ive dived with a few guys who were always hunting for quick deco. Both of them still dive and dive deep, but both of them have permanent neurodamage sustained on dives we did together where I did signif longer deco than them. That may be a coincidence but it is something I consider when the urge to cut deco time starts to be so strong Mike - are we meeting for that beer/dinner (give me a call or email me 09285031475) I can introduce you to some good bag handlers you were talking about earlier.
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