"I was just reading over this thread and wondering where the different times for different depths come from? Are they just that different programs have different ways of doing it? Say one would keep you at 70' a while longer but the other would make up for it at a higher depth?"
Yeah, the two programs are using different alogorithms to calculate deco. VPM is relying on the deep stops more than Deco Planner (modified Bruhlman).
"Also, when you all go diving do you just plan all of this with the software and then write down several different contingency plans? It seems like it would be very hard to plan 2 or 3 days of diving several times a day without having a computer on hand."
Yeah, we have a primary plan; a plan with 50% deco; and a plan with a significaltly extended BT. I generally don't do mutiple days of technical diving. In fact, we usually only do one (two max) deep dive per day. I have a book of premade tables that I take with us on every dive trip of profiles for first dives and second dives that we would likely do.
"Say if you miss one of your stops, would you just go way conservative?"
Discipline is important in this type of diving, so missing stops would only result during some sort of emergency. This is one advantage of deep stops and the 50% gas switch at 70'. It allows you to off gas quicker and deeper in case you have to blow through the shallow stops. They certainly don't guarentee that you won't get bent if you miss your shallow stops, but they may effect the severity.
"I have never heard of tables that one can take with them diving that can be used for trimixes, or can you computate equivalent stats with basic Navy tables?"
Using computer generated tables is the norm in technical diving as there are so many variables that need to be considered (bottom mix, deco mixes, time, etc.). There may be "hard" trimix tables (used by commercial and military divers), but I haven't seen them.
Take care.
Mike
