Using the dive planner (new user)

Hi. I am new to the Descent MK1 (and diving in general), and have a basic question. I’m trying to figure out the dive planner. It seems that it computes NDL, assuming you’ll max out your dive? Ie., you enter depth and it tells you maximum minutes or you enter minutes and it tells you max depth, both of which get you to the NDL threshold? I’m trying to figure out how I would plan a dive that falls under the NDL for the dive, and then factor the residual nitrogen into the next dive, similar to how it would be done using the RDP tables. Maybe I’m thinking about it wrong. Can anybody give me some insight on this?

Thanks,
Mark

  • hi 

    I am very confused by the dive planner on the MK2 as the results are way more conservative than the Perdix I have, or the Baltic deco planner software that I use. As for your comment on conservancy, my understanding is that this should be implemented using Gradient Factors (high and Low). This allows the team to all be diving with the same parameters even if using different hardware. 

    Dive planning is extremely important when tech diving or solo diving because it feeds into gas planning, getting bent is a serious issue which may lead to death, running out of gas at depth is a more serious problem. If the planner says you have 12 mins of bottom time and you end up having 15 mins before You have to get to your first deco on the actual dive, you have a choice, cut your dive to the plan or push the gas. Obviously you should dive the plan, but you would not use the planner again as it does not mirror your in water experience. 

    The issue for me is that I bought a Dive computer that uses the Buhlman ZHL16 algorithm so that I would have predictable results when calculating my deco. This is not the case with the planner. I am disappointed. Garmin needs to sort this out. If Garmin took the view that they would build in extra conservancy and not tell anybody, they really should not market to tech divers who at least have a working knowledge of deco theory and have other resources that they would check against. The beauty of Buhlman is that it is published and predictable, if they are not going to implement the algorithm then they end up competing with suunto rather than shearwater and suunto is much cheaper than either.