VPM V-planner help

[W Wilberforce]

Hello all,
I was advised to get some software tables to carry as backup for my trusty apeks
quantum when solo diving ( i like to use 80% for accelerated deco'ing ). I decided to buy V-planner as various people have talked about it and it seems popular.

However, when i put it into practice I am finding that it gives short shallow stops and lots of apparently OBLIGATORY deep stops, is this correct and usual?

Also it seems to use a completely new physical bubble model ('VPM') and was wondering if people have had much success on it and, more importantly, what safety factor they use and if it's best to use VPM or VPM b/ / b/e. Hope to be diving up to 50metres on air/ nitrox.

Also is it best ( cuts most time) to use weak nitrox and switch early or to do air up to 10m and use 80/ 100? (because of the deep stopping)?

Any information would be great!
Thanks
Will

[finbar.taylor]

Originally Posted by spunkmire

Hello all,
I was advised to get some software tables to carry as backup for my trusty apeks
quantum when solo diving ( i like to use 80% for accelerated deco'ing ). I decided to buy V-planner as various people have talked about it and it seems popular.

However, when i put it into practice I am finding that it gives short shallow stops and lots of apparently OBLIGATORY deep stops, is this correct and usual?

This is normal for VPM. By adding the deep stops your reducing the stop times of the shallower stops

Originally Posted by spunkmire

Also it seems to use a completely new physical bubble model ('VPM') and was wondering if people have had much success on it and, more importantly, what safety factor they use and if it's best to use VPM or VPM b/ / b/e. Hope to be diving up to 50metres on air/ nitrox.

There are a lot of people using it on some very serious dives. You can change the safty factors in the config options I personaly use VPM b with a safty factor of 2

Originally Posted by spunkmire

Also is it best ( cuts most time) to use weak nitrox and switch early or to do air up to 10m and use 80/ 100? (because of the deep stopping)?

If the table is cut to switch at 10m then switch at 10m if cut to switch at 21 then likewise switch at 21.

Originally Posted by spunkmire

Any information would be great!
Thanks
Will

I would recomend going back to your instructor and asking them to run over the theory of deco again or similary Mak Powell is runnign some deco theory lectures which I can highly recomend!

Fin

[rossh]

Originally Posted by spunkmire

However, when i put it into practice I am finding that it gives short shallow stops and lots of apparently OBLIGATORY deep stops, is this correct and usual?

That would depend on the settings you have selected. The Extended stops controls this area. See the help file (press F1), and adjust your settings to see the changes.

Regards

[Mark Powell]

Originally Posted by spunkmire

Hello all,
I was advised to get some software tables to carry as backup for my trusty apeks
quantum when solo diving ( i like to use 80% for accelerated deco'ing ). I decided to buy V-planner as various people have talked about it and it seems popular.

However, when i put it into practice I am finding that it gives short shallow stops and lots of apparently OBLIGATORY deep stops, is this correct and usual?

For a bubble model this is correct and usual. A bubble model puts emphasis on deep stops to stop bubbles growing during th ascent and so reducing the need for long deco stops in the shallows.

Originally Posted by spunkmire

Also it seems to use a completely new physical bubble model ('VPM') and was wondering if people have had much success on it and, more importantly, what safety factor they use and if it's best to use VPM or VPM b/ / b/e. Hope to be diving up to 50metres on air/ nitrox.

VPM is the original model and was very aggressive - Do not use this version - VPM-B is much better and is the one I would recommend for most people. VPM-BE is for extreme dives and unless you are in the advanced Trimix range doesn't really need to be considered. For UK diving I recommend +2 or +3 conservatism as normal.

I would also recommend using Trimix at 50m and to take a suitable buddy but that's not a V-Planner issue.

Originally Posted by spunkmire

Also is it best ( cuts most time) to use weak nitrox and switch early or to do air up to 10m and use 80/ 100? (because of the deep stopping)?

This will depend a lot on the profile. As a bubble model gives you deeper stops a deco gas (like 50%) which you can switch to deeper will give more of an advantage with a bubble model then a traditional Buhlamnn model.

Originally Posted by fin

I would recomend going back to your instructor and asking them to run over the theory of deco again or similary Mak Powell is runnign some deco theory lectures which I can highly recomend!

Welcome back fin! The lecture Fin is talking about is
Feb 24th Decompression Theory and Physiology

Originally Posted by spunkmire

my trusty apeks quantum

I also use an Apeks Quantum, one of the reasons I like these is that they do not penalise you for deep stops. Unlike some other computers which add on more time for deep stops the Quantum will still credit you for a 21m stop even if it thinks your deco ceiling is at 6m. Obviously it will count down slower but it still counts down so you can manually put in deep stops or follow a VPM type profile and the Quantum will quite happily match it. I find the Quantum on +1 with manual deep stops matches VPM +2 quite closely for overall run time.

[Skiverdiver]

Originally Posted by Mark Powell

Welcome back fin! The lecture Fin is talking about is
Feb 24th Decompression Theory and Physiology

Sorry to hijack thread.

Mark,

Are you running this course down south some time??....

Roy

[markosis]

Mini Me uses V Planner a lot, he'll help you out if you phone him.

[MJH]

Originally Posted by Skiverdiver

Sorry to hijack thread.

Mark,

Are you running this course down south some time??....

Roy

He did and you missed a really great lecture!

Definitely worth driving to Nottingham for

[Skiverdiver]

Originally Posted by MJH

He did and you missed a really great lecture!

Definitely worth driving to Nottingham for

Doh!....

Thanks

Roy

[W Wilberforce]

Hello all again,
thanks for all your help. Will be trying out the runtimes on the New Year with some (one) of you and hope it goes well!
Unfortunately my TDI decompression procedures course was done at Deep Blue diving which is not answering its telephone regularly which is why I am on here surfing the information superlowway.

V-planner finally send me through the unlocking keys for mixed-gas calculations, looking at the results it seems better to use weaker gas (50%) starting deeper than stronger (80%) later in the ascent, if that makes sense (i.e. it gets me out of the water quicker).
As for buddies, well iv'e tried but they just can't keep up no seriously I am too
dopey to stick with my buddy on the good dives. The course is interesting but seems a bit expensive when I am using nitrox mixtures only for recreational diving, though will be useful, in the future maybe.
Also I am diving that weekend. Will look out for the book if and when it hits the shops.
Now I only have to work out how to fit my laptop into the waterproof see-through box unfolded!

Thanks for all your help,
will call/ email Rich about it soon thanks for the tip Mark! See you on the 13th
Will