Use of a Dive Computer and Planning the Dive with a Desktop Software

[exposure]

I use to plan my deco dive with V-Planner and dive the plan on a slate with two basic computers on gauge mode. So I just follow my plan without surprise, and I am fine with that. But as I want to do more and more deco dives I wonder if buying I dive computer like OSTC MKII or Liquidvision or even Shearwater could be a nice choice or add some uncertainty in diving. So then I have a question: When you plan a dive with V-Planner or other softwares, your planning will follow the decompression model that is on your software and you plan your gas consumption according to this model too, including the reserve. The decompression model can be different than on the computer software (ie. VPM for V-Planner versus ZHL16 for the OSTC MKII). Then different case can happens:
- Your dive plan is longer on deco than the dive computer, so that's fine you follow the dive plan, there's no surprise.
- Your dive plan is less conservative than the dive computer but not very far, so I guess you will follow the dive computer instead of your slate and probably use your reserve. Am I right?
- Your dive plan is really really less conservative than the dive computer so by following it you'll be in trouble with your gas comsumption. What to do in this case?

As generic question, how do you manage your dive when planning your dive on a desktop software (deco stops and gas consumption) then dive your plan on a slate with a dive computer?

Yvan

 

[DuboisP]

also depending of the buddy equipment

i plan my dives with vplanner, and i have a OSTC MKII, but not my buddy.
so, we dive the runtime(s), and the OSTC is here in case of less/more time, less/more depth, although we also plan emergency runtimes...
you can run the OSTC with LH16 - Gradient Factors, and it's possible to set LH16 GF and/or VPM settings to be close to the other.

options :
- your computer is running VPM-B and you're using V-Planner. same durations
- your computer is running LH16 GF and you're using MV-Plan (example, or others) with GF. same durations
- adjust as noticed
- and add time if needed...

 

[RTee]

In my case, they are both the same.

My Shearwater Predator is presently running Buhlman which also happens to be the algorythm of MV-Plan, the software i use to cut my tables. Shearwater recently announced a VPM-B algorythm through their news letter. Not sure yet if I am going to go that route or not as it is impossible to get a V-planner laptop/desktop and a mobile device license under one subscription.

During my AN/DP course, my instructor had two Nytek computers. Not sure if he cut his tables from MV-Plan or V-Planner but I did cut mine from MV-plan and then we dove the same mixes, followed our runtimes but stuck to the most conservative schedule coming up...and it worked out just fine. In some scenarios, there is very little difference.

 

[Red Sea Shadow]

Best bet, IMHO, is to use a software that incorporates both VPM-B and Buhlmann-GF.

 

[ianr33]

Just use planning software that matched the computer. Problem solved.

 

[exposure]

Thanks for your feedback. I was looking at the OSTC MKII but as my computer is a Mac, it seems that the only one choice for desktop software is V-Planner. That's why my question, but sure it make more sense to run the same software on the computer and the desktop.

 

[Bombay High]

Asser Salama - On a Trimix dive to, say, 80 metres with a 15 minute bottom time, if you ascend on a strict Buhlmann model in one case, and if you ascend on a strict VPM-B model in the other case, do you find a difference in the way you feel later ?
I ask this because I feel very different using the 2 models on Trimix dives. VPM-B seems to suit me a lot better. It is not the case with Nitrox or Air dives.

 

[down4fun]

Thanks for your feedback. I was looking at the OSTC MKII but as my computer is a Mac, it seems that the only one choice for desktop software is V-Planner. That's why my question, but sure it make more sense to run the same software on the computer and the desktop.

For us it's not really a problem to run your planner off of one software and have your actual computer be another. FWIW we are on rebreathers. We have mac's in the house and V-planner but dive shearwater's. After a few dives you can figure out which settings most closely align. The actual stops and times will vary. We only use the V-planner for rough planning and a set of back up tables for the Oh-s*** mode. It helps with gas planning and rough run time. Then we each have two shearwater's so the chance of having to go to tables is pretty slim.

 

[DuboisP]

Thanks for your feedback. I was looking at the OSTC MKIIn but as my computer is a Mac, it seems that the only one choice for desktop software is V-Planner. That's why my question, but sure it make more sense to run the same software on the computer and the desktop.

jdivelog and mv-plan (incorpored in jdivelog) are pure java programs and can be run on windows, linux and mac_osx.

mac_osx packages are available
JDiveLog » Download | the open source logbook for scuba divers
JDiveLog » Téléchargement | the open source logbook for scuba divers
http://www.jdivelog.org/how-to/mac-os-x/

http://www.users.on.net/~wittig/diving/mvplan_download_alternate.html

 

[Red Sea Shadow]

Asser Salama - On a Trimix dive to, say, 80 metres with a 15 minute bottom time, if you ascend on a strict Buhlmann model in one case, and if you ascend on a strict VPM-B model in the other case, do you find a difference in the way you feel later ?
I ask this because I feel very different using the 2 models on Trimix dives. VPM-B seems to suit me a lot better. It is not the case with Nitrox or Air dives.

Personally I don't use Buhlmann-GF for planning my dives.

My reply was to how match your software-generated plan with your real-time dive computer.