Why are my Vytec and Cobra so different?
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You're right... but once edited, we could still compare the two. And run the sim on it.
Even if you've edited it, it won't necessarily prove your point, because the software will still generate different sims.
Perhaps it's just your Cobra that's messed up, Karl.
And my Vyper is also identically messed up?
I own one of each, and they behave the same way....
BTW, don't believe the "conservatism" of the Suuntos you hear about. Take some of the profiles that you generate with those Suuntos and feed them into VPlanner - you might get a surprise or two....
I own one of each, and they behave the same way....
BTW, don't believe the "conservatism" of the Suuntos you hear about. Take some of the profiles that you generate with those Suuntos and feed them into VPlanner - you might get a surprise or two....
Charlie99
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I don't understand why anybody would doubt what Karl reports. Jamiei makes a lot of noise, but the few number Jamiei has provided agree with Karl.
Suunto says that they have significantly reduced limits on O2 CNS exposure between 1.4 bar and 1.6 bar on the Vyper and Cobra.
Karl's main complaint is that the limits are significantly reduced, even if you set the alarm to 1.6 bar/ata. I fully believe him, since that's what the manual says the Cobra will do.
Since that "problem" exists, it isn't a big stretch of the imagination that the exact point at where the CNS limits are reduced and the 1.4bar/ata alarm go off might differ by a foot or two. That is Karl's secondary complaint. While since it is subtle, and therefore hard to show clearly, it is easy to believe since Suunto uses the term "BAR" in the manual and 1.4 BAR is at 105.2', not 107' that is 1.4ata for FO2 of 33% (which Suunto uses if you enter 32.
Being newly married (Aug 2nd), having to build a lot of interfaces, showing people my puppies, along with the many other things I have to do with my life (real job), I have not been able to video the simulation process yet (I wanted to have it by this past friday). I did the simulation dives on my cobra only so I don't know of a good way to download the simulation to divemanager. There is quite a bit of doctoring that one can do no doubt, but a video of the simulation from start to end (showing po2 setting and fo2 settings) can't be rigged that I know of.
We all agree that the OLF calculations are at a faster rate when you reach suunto's MOD of a particular mix. This only occurs when you maintain this MOD. In doing a dive like the one mentioned before, you one hit 107' about 1.5-2 minutes into the dive and remain at 107' until around 22 minutes before the OLF actually goes into the yellow and red. The OLF graph increases at a steady rate from the time you hit 107' until the end of the dive. This gives you 15 minutes or more to notice the faster rate. It is the diver's responsibility to pay attention to the OLF graph. In 15 minutes I think anyone has plenty of time to see when they need to end the dive. To some I think this may not be clear. The OLF graph does not jump from 10% to 100% during the last few minutes of the dive. It is a constant, gradual increase.
A few complain that this would cause a dangerously quick ascent because there is no warning. All you have to do is take a look at your dive computer every minute or so as you should anyway and you can easily see that the OLF graph is climbing. Again, it doesn't stay at 10% for the first 10 minutes of the dive and then all of a sudden jump to 100%. The diver has plenty of time to notice that their OLF graph is filling up faster than usual and they will have to call the dive soon. A diver that pays their computer no attention and also doesn't plan thier dive using tables as backup is looking for trouble anyway and is indeed an accident waiting to happen. You can't protect these divers. If you don't know your limits its your own fault, not a computers. I've never heard a single person say that you should rely on your computer, any computer. Karl doesn't even rely on his vytec (as he shouldn't). If a person happens to be a bad enough or unexperienced enough diver that they don't know what to expect and rely completely on thier dive computer, they shouldn't be diving anything other than air and shouldn't be diving anywhere near the depths that these problems occur usually in the first place. I would argue that they shouldn't be diving at all. Can't we all agree on that? Do any of us really think that all these factors would ever come together for such an accident to happen? Would this type of diver really sit at 107' for 15 mihutes or more? Would any of us? Ever? No one has mentioned it? And if they had and had the dive log to show it this thread wouldn't still be going.
As far as proof and doctoring and whatever else, can we all agree that a video of a simulation would rule out those possibilities? In addition to that... not a single one of us knows that any of the simulations are anywhere near an accurate measure of how the dive computer will react during an actual dive. The dive simulation, in my eyes, is a simple and most likely unreliable measure of a dive computer's dive calculations. If I can find a buddy to make the dive with me soon, I want and plan on attempting to duplicate the 107' for 15 minutes dive that has up til now only been simulated. Not to prove my simulation or disprove anyone elses, but more importantly see if these simulations are accurate at all and if the simulation, even while trying my best, can even be duplicated during a dive. Thats the most important thing. I don't care to doctor anything because it doesn't do me or anyone else any good. Does anyone think that a video of the simulation would not be valid? Again, if any simulation is valid in the first place...
Charlie, my numbers don't agree with everything Karl has said. The rate is faster, we all know that and as you've said Suunto says it in the manual so it doesn't really matter that its faster. The graph I've posted doesn't reach 100% at 15 minutes as originally reported by Karl. The question isn't whether its faster or not, but that this faster rate has been overstated at times. On a normal dive profile, 60-70% of the OLF graph is used up at 15 minutes instead of 90-100%. Thats a considerable difference to me. Again, we all agree the rate is faster, but thats suunto's call because its their computer and they make note of the faster rate. It's our choice to buy it or not. Once we buy it, we can't expect to change the way it was built whether it matches up to the standards of the tables we want it to or not. If we wanted a computer that was equal to or more liberal than the tables, we should buy a different computer. You can compare the suunto's NDLs in plan mode to any table and see that its more conservative. It is a recreational dive computer and most of the dives mentioned, while within the limits of the tables, push the limits much more than the vast majority of divers ever will intentionally. While the cobra and vyper do feature decompression calculations, this is for safety more than it is a feature to plan and execute decompression dives. I think you'll also find that in the manual. It's more conservative than anything I've compared it to ( I did a project for school comparing tables and various dive computers). Anyone?
We all agree that the OLF calculations are at a faster rate when you reach suunto's MOD of a particular mix. This only occurs when you maintain this MOD. In doing a dive like the one mentioned before, you one hit 107' about 1.5-2 minutes into the dive and remain at 107' until around 22 minutes before the OLF actually goes into the yellow and red. The OLF graph increases at a steady rate from the time you hit 107' until the end of the dive. This gives you 15 minutes or more to notice the faster rate. It is the diver's responsibility to pay attention to the OLF graph. In 15 minutes I think anyone has plenty of time to see when they need to end the dive. To some I think this may not be clear. The OLF graph does not jump from 10% to 100% during the last few minutes of the dive. It is a constant, gradual increase.
A few complain that this would cause a dangerously quick ascent because there is no warning. All you have to do is take a look at your dive computer every minute or so as you should anyway and you can easily see that the OLF graph is climbing. Again, it doesn't stay at 10% for the first 10 minutes of the dive and then all of a sudden jump to 100%. The diver has plenty of time to notice that their OLF graph is filling up faster than usual and they will have to call the dive soon. A diver that pays their computer no attention and also doesn't plan thier dive using tables as backup is looking for trouble anyway and is indeed an accident waiting to happen. You can't protect these divers. If you don't know your limits its your own fault, not a computers. I've never heard a single person say that you should rely on your computer, any computer. Karl doesn't even rely on his vytec (as he shouldn't). If a person happens to be a bad enough or unexperienced enough diver that they don't know what to expect and rely completely on thier dive computer, they shouldn't be diving anything other than air and shouldn't be diving anywhere near the depths that these problems occur usually in the first place. I would argue that they shouldn't be diving at all. Can't we all agree on that? Do any of us really think that all these factors would ever come together for such an accident to happen? Would this type of diver really sit at 107' for 15 mihutes or more? Would any of us? Ever? No one has mentioned it? And if they had and had the dive log to show it this thread wouldn't still be going.
As far as proof and doctoring and whatever else, can we all agree that a video of a simulation would rule out those possibilities? In addition to that... not a single one of us knows that any of the simulations are anywhere near an accurate measure of how the dive computer will react during an actual dive. The dive simulation, in my eyes, is a simple and most likely unreliable measure of a dive computer's dive calculations. If I can find a buddy to make the dive with me soon, I want and plan on attempting to duplicate the 107' for 15 minutes dive that has up til now only been simulated. Not to prove my simulation or disprove anyone elses, but more importantly see if these simulations are accurate at all and if the simulation, even while trying my best, can even be duplicated during a dive. Thats the most important thing. I don't care to doctor anything because it doesn't do me or anyone else any good. Does anyone think that a video of the simulation would not be valid? Again, if any simulation is valid in the first place...
Charlie, my numbers don't agree with everything Karl has said. The rate is faster, we all know that and as you've said Suunto says it in the manual so it doesn't really matter that its faster. The graph I've posted doesn't reach 100% at 15 minutes as originally reported by Karl. The question isn't whether its faster or not, but that this faster rate has been overstated at times. On a normal dive profile, 60-70% of the OLF graph is used up at 15 minutes instead of 90-100%. Thats a considerable difference to me. Again, we all agree the rate is faster, but thats suunto's call because its their computer and they make note of the faster rate. It's our choice to buy it or not. Once we buy it, we can't expect to change the way it was built whether it matches up to the standards of the tables we want it to or not. If we wanted a computer that was equal to or more liberal than the tables, we should buy a different computer. You can compare the suunto's NDLs in plan mode to any table and see that its more conservative. It is a recreational dive computer and most of the dives mentioned, while within the limits of the tables, push the limits much more than the vast majority of divers ever will intentionally. While the cobra and vyper do feature decompression calculations, this is for safety more than it is a feature to plan and execute decompression dives. I think you'll also find that in the manual. It's more conservative than anything I've compared it to ( I did a project for school comparing tables and various dive computers). Anyone?
Eyyeball
Guest
I've lost all interest in the content of the argument at this point, now I'm just scanning for more insults.
cornfed
Mindless lemming
Then there really isn't any need to reply, now is there?
Way to make a good impression with your first post!
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