When is ZH-L16C GF not ZH-L16C GF? When it is a G2 Tek computer

[lexvil]

So the “plan” is flexible, if everything goes sideways do you adapt or die, DCS is a bit more treatable than drowning. All computers only offer solutions based on guessgorythims anyway since every persons physical needs are different and some times change.

The lock out is a disappointing “feature” but I understand the point behind it which isn’t much different than the instructor who only allows shearwater.

 

[stuartv]

So the “plan” is flexible, if everything goes sideways do you adapt or die, DCS is a bit more treatable than drowning. All computers only offer solutions based on guessgorythims anyway since every persons physical needs are different and some times change.

Obviously, we adapt. The question is, which computer decides HOW to adapt? The one on your wrist, or the one between your ears?

The lock out is a disappointing “feature” but I understand the point behind it which isn’t much different than the instructor who only allows shearwater.

I'm not sure I follow how a computer that will lock out and an instructor that only allows Shearwater are "not much different".

What I will say from an instructor's point of view are the following:

- I'm not able to be fully proficient and knowledgeable about every computer on the market. Not even every tech-capable computer. And I kinda feel like it would be unreasonable for a student to expect that.

- I need for my students' computer to behave in a way that is predictable and that I expect. Giving a really long deco stop when nobody else on the dive had a deco stop at all was - from my perspective - not something I could predict or would have expected. As such, I choose not to accept future students that use that computer. I.e. based on both the manual (as reported by Sevenrider860) and my personal experience, I find that computer unacceptable for use in tech diving.

- In the future, I may be asked to teach someone with some other non-Shearwater computer that is purported to be tech-capable. Say, for for example, a Ratio or HW OSTC computer. As I don't KNOW those computers, accepting that would run the risk of finding out that, like the G2Tek, that other computer behaves in some unpredictable and unexpected way that makes it unacceptable for tech diving. Maybe not. But, as I am not fully proficient and knowledgeable on those other computers, I would not want to run the risk. I would accept other computers, as long as the student has at least one Shearwater. I might even rent or loan a Shearwater to a student that doesn't have one. But, I don't think I would take on another student that did not have a Shearwater and wouldn't use one that I provided. They can do whatever they want after (if) they finish their certificaiton. I am not the Scuba Police. But, it disrupts the class and impedes progress when you have to deal with a computer that does not work as expected.

 

[Kendall Raine]

and it is nothing to do with teams.

Perhaps for solo divers, but if the team consists of a dive team plus surface support (support divers and boat crew), not knowing your deco time in advance because the computer is doing it on the fly based on proprietary coefficients for each diver then team planning (e.g. gas, CNS%, etc) kind of goes out the window and the team is left with decoing to the most conservative schedule not known in advance.

I agree with you this kind of "ad hoc" deco has no place in technical diving. Divers can modify the deco based on how they feel (stress, exertion, sleep, etc), but relying on a black box to tell each diver their required deco based on mysterious coefficients (aka "see you when I see you" dive planning) doesn't work for me.

 

[BoltSnap]

I hope that you guys eventually and soon will narrow down your complaints and reasoning in a more concise way so that I can go back to SP with a concise and comprehensive report/complaint

At this point, the initial OP complaint/observation and supported by @stuartv that appeared to be strong and to the point is now diluted and appear to be just personal "opinions" from people with different tastes (with dogma and loyalty to one brand's way of doing things).

 

[stuartv]

I hope that you guys eventually and soon will narrow down your complaints and reasoning in a more concise way so that I can go back to SP with a concise and comprehensive report/complaint

At this point, the initial OP complaint/observation and supported by @stuartv that appeared to be strong and to the point is not diluted and appear to be just personal "opinions" from people with different tastes (with dogma and loyalty to one brand's way of doing things).

What is our motivation to do this work for you?

 

[BoltSnap]

What is our motivation to do this work for you?

1. Determine if there is actually an issue or it is a "user error/misunderstanding."

2. If it is a real issue caused by mfg., you can have a say in "addressing/solving/correcting" the issue.

3. If you just want to whine, you don't have to do anything.


P.S. It isn't for "me" really.

 

[lowwall]

I hope that you guys eventually and soon will narrow down your complaints and reasoning in a more concise way so that I can go back to SP with a concise and comprehensive report/complaint

It doesn't seem that complicated to me. All they are asking for is a true technical deco mode: straight ZH-L16C with the only modifications a result of the user selected Gradient Factors and no more than 3 ascent rates which are either fixed or (better) user selectable within each depth range.

It doesn't have to be the only deco mode if they want to keep their existing algorithm as the default.

 

[BoltSnap]

It doesn't seem that complicated to me. All they are asking for is a true technical deco mode: straight ZH-L16C with the only modifications a result of the user selected Gradient Factors and no more than 3 ascent rates which are either fixed or (better) user selectable within each depth range.

It doesn't have to be the only deco mode if they want to keep their existing algorithm as the default.

Perhaps a question about what changes/modifications (if any) SP made to their algorithm first? (In addition to what you said)

 

[stuartv]

1. Determine if there is actually an issue or it is a "user error/misunderstanding."

2. If it is a real issue caused by mfg., you can have a say in "addressing/solving/correcting" the issue.

3. If you just want to whine, you don't have to do anything.


P.S. It isn't for "me" really.

I posted screenshots of 3 portions of the manual. I verified that what Sevenrider860 quoted from the manual is also in there.

Those are the issues. I don't believe I have misunderstood the manual. They are real issues.

I have no real investment in whether they change their computer.

I'm not whining. I have done my analysis and posted my thoughts.

I'm really done with this thread, other than friendly banter with you, my esteemed colleagues.

If you want to tilt at ScubaPro windmills, have at it. But, I'll not be your steed. I'm happy in the peanut gallery.

 

[Sevenrider860]

1. Determine if there is actually an issue or it is a "user error/misunderstanding."

2. If it is a real issue caused by mfg., you can have a say in "addressing/solving/correcting" the issue.

3. If you just want to whine, you don't have to do anything.


P.S. It isn't for "me" really.

I think it is pretty clear. Scubapro claims they have implemented ZH-L16C with Gradient Factors in the G2 Tek. This is an open algorithm and it exists because users of this specific algorithm expect it to to generate NDL times and decompression stops in a specific and expected manner that can be replicated across multiple dive computers and offline computer programs/apps. Users expect that they can change initial stop depths and final surface gradient settings using the same gradient factor values they use on other computers or offline programs/apps and get similar results.

My personal experience shows that the computer is not implementing ZH-L16C with Gradient Factors in a manner that matches products from Garmin and Shearwater. Scubapro Tec Services has stated "I will note that our unit is more conservative intentionally."

In the end, I don't care what Scubapro does. I have reported my findings to Scubapro and they have stated that they have intentionally implemented an algorithm that is more conservative. To me, that means they have not implemented a valid Buhlmann ZH-L16C algorithm.

I personally think implementing a standard Buhlmann ZH-L16C with GF algorithm would have been to their benefit. If the G2 Tek implements the same algorithm and behaves the same was as the Shearwater and Garmin computers, then a Scubapro dealer could sell more of these in the technical diving space. Dealer margins on the G2 Tek are much higher than margins on Shearwater or Garmin. They seem to think differently.