Why are my Vytec and Cobra so different?

[Genesis]

BTW, CNS "clock" exposure for a dive at a PO2 of 1.6, with an actual bottom time of 20 minutes, is 13%.

This according to the SSI tables, once again.

According to Suunto, the actual loading is close to TEN TIMES that value.

They're simply wrong.

(The "acceleration" happens when you get within a foot or two of the MOD - without warning. If you are at 105 and tooling along, you see nothing unusual. 2' deeper and suddenly the computer is loading at a rate that grossly exceeds the actual clock exposure, even though no alarm has sounded to warn you of the incursion below the MOD. Worse, if you set an acceptable exposure of 1.5 or 1.6, you STILL get penalized, even though you've intentionally requested a higher exposure limit.)

 

[Genesis]

They represent commonly-accepted limits.

Now small differences between tables, or between tables and computers, are to be expected.

But a 1,000% difference? C'mon Jamie. That's obviously an eror. Its so obvious that unless someone is paying you to shill for the people who made the mistake I find it nearly impossible to believe that you would take the opposing point of view.

Go ahead and bleat in reply - the facts are what they are on this one.

 

[jamiei]

I never said the dive profile pushed the limits of the tables now did I?

What I said was that it pushed the limits of the computer's algorythm which is what really counts when talking about using the computer isn't it? Do you want to talk about a suunto or tables? They aren't the same... Use one or the other.

show me 1000%? Again, the OLF is in no way comparible to the CNS O2 clock. Thats what you are comparing and the two aren't even taking into consideration the same info. The CNS clock is for all dives in a 24 hour period. The OLF graph represents that dive only. Try a different mix to its suunto MOD and see what happens. Its the same thing. You can't sanely expect the suunto computer to abide by your tables. They make their own rules. How many people have actually made a dive to 107' for over 15 minutes on 32%? How many would? So does it really matter? Would it make you feel better if suunto officially said, do not dive to 107' with our computers using 32% nitrox?

One other question for you... when you do these simulations using the vytec, are you using the factory conservative settings or are you using the more liberal setting? I can confirm it as well if need be. You haven't mentioned the last pic I posted? its a simulation of what an actual dive would look like to 107'.

 

[jamiei]

If its 1000% faster (10x quicker OLF increase, right?) , I should be able to get in about 220 minutes at 106' using the cobra, right? Thats what you're saying, you are comparing the cobra to itself aren't you? You couldn't possibly be once again comparing it to the tables could you? Of course, you are and that doesn't mean a thing.
You say that there's his terrible bug at 107' that's so much faster accerlating than at 106' (1000%, so fast you can't detect it in time) but you get this info based on the CNS O2 limits of a table, not the dive computer. You're saying its errored as compared to the tables, which of course, it isn't based on.

 

[Genesis]

They make their own rules. How many people have actually made a dive to 107' for over 15 minutes on 32%? How many would? So does it really matter? Would it make you feel better if suunto officially said, do not dive to 107' with our computers using 32% nitrox?

They'd be lying.

I made a dive Saturday to a depth of 137' maximum with a total runtime of 31 minutes (15 minutes of actual bottom time between 115 and 137, most of it in the mid to upper 120s) on 28% Nitrox.

Over 1.4 PO2 according to the Suunto. That very computer, at the end of the dive, showed TWO - count 'em - TWO - bars on the OLF graph. (Oh, that was a deco dive too.....) Wanna see the profile?

How come? The computer in question is a Vytec and doesn't have the bug.

Again, this is a specific problem (bug) with the Vyper and Cobra. It does NOT extend to the Vytec.

 

[jamiei]

The conservatism on the vytec can also be made more liberal as I'm sure it was set for that dive. yes... more BS from you

by lying about what? that comment made no sense... again... put on a spin... who's talking about the vytec? we know you can make it more liberal to make that dive doable with the vytec... you're saying all the cobras, vypers, and I assume mosquitoes are all errored, right? Or just the old or new?

as I have said, 28% is the mix you should be using on the 107' dive anyway. conservatism is the key...

To karl, the bug is that the vyper and cobra aren't vytec's... they're different because they are set conservatively. The vytec is a more advanced, technical use computer that can be set to much more liberal than the vyper or cobra. Thats no bug at all. It's a design feature.

 

[Genesis]

The conservatism on the vytec can also be made more liberal as I'm sure it was set for that dive. yes... more BS from you

Nope. RGBM100, conservatism was set to normal.

The Vyper and Cobra have a BUG in their implementation Jamei. It really is that simple. The same profile on a Vytec does NOT show the problem, and I do NOT dive with attenuated RGBM!

Any more questions, and are you man enough to retract the accusation that I set the computer for "liberal" mode yet?

The CNS computation for the Vyper and Cobra is BROKEN.

My Vytec is NOT set to be less conservative, nor are my Cobra or Vyper set to be MORE conservative.

 

[cornfed]

Genesis once bubbled...

There are subtle differences in the NDL computation, and VERY NOT SUBTLE ones in the CNS loading.

Heard anything from Suunto yet?

 

[SM Diver]

Wow, scubaboard sure as hell has become more liberal since I used to hang out here. I haven't seen a thread this ugly since Uncle Pug posted a picture of his boat.

 

[Genesis]

Heard anything from Suunto yet?

As I noted earlier in the thread, Aqualung (their US distributor) said "we don't know why that is" but Suunto Finland has not responded.

At all.