Atomic Aquatics Cobalt Dive Computer

[Dr. Lecter]

What lb said. From what I recall, if you're spending the whole dive around 30' or shallower, it just doesn't trigger one.

 

[jlevine]

I just bought a Cobalt!

My 1st gen Cobra totally died after several years and was way out of warranty. So, I went back and forth between the Oceanic Pro Plus 3 and the Cobalt and decided to go with the Cobalt. Having this jumbo thread really helped me to make the decision. I can't wait for my next trip!

 

[RonR]

Hi Ron:

I’ve just returned from my second dive trip with my Cobalt working in tandem with an Oceanic OC1 (with wireless integration) as a backup unit. The unit is working great – but I’ve noticed one thing that I’d like your input on.

All of my dives are either two or three tank dives. The first dives – everything works perfect and the Cobalt initiates the 3 minute safety stop routine as I reach about 19 feet to end the dive. Perfect.

On dives two and three (when there is a third dive), my Cobalt does not initiate the 3 minute safety stop routine as I end my dives – it just continues to operate in the normal diving mode all the way through my surfacing. The OC1 on my wrist initiates it’s own 3 minute safety stop routine without fault, and I’ve followed that with no issue.

This pattern repeated itself each day whilst diving this past week and last month.

My question is, is there a setting on the Cobalt that I need to change so that it will initiate the 3 minute safety stop routine on each incremental dive on any given day?

Let me know.

Thanks !

John

Can you give some more information as to the dive profiles, and firmware version of the Cobalt?

Dives shallower than 40' won't necessarily trigger a safety stop, it's not just a mechanical process on every ascent, as it is on some dive computers. We use an algorithm for determining the need for a safety stop- for divers who are bouncing around in the 39' to 15' zone, we don't want to be constantly generating safety stop alerts. And when your dive is that shallow, the safety stop is a non issue as far as actual safety is concerned. In effect, it would just make your dive longer.

If your subsequent dives were deeper than 40' and didn't generate a safety stop, that would be something we would want to look at further.

Ron

 

[master_diver_UJ]

Can you give some more information as to the dive profiles, and firmware version of the Cobalt?

Dives shallower than 40' won't necessarily trigger a safety stop, it's not just a mechanical process on every ascent, as it is on some dive computers. We use an algorithm for determining the need for a safety stop- for divers who are bouncing around in the 39' to 15' zone, we don't want to be constantly generating safety stop alerts. And when your dive is that shallow, the safety stop is a non issue as far as actual safety is concerned. In effect, it would just make your dive longer.

If your subsequent dives were deeper than 40' and didn't generate a safety stop, that would be something we would want to look at further.

Ron

Hi Ron:

Thanks for taking a look at this. I don't have my logs or the Cobalt with me at work today, so I can't give you exact numbers. I'll sign back in this evening and post some dive information (dive length, max depth) on a three-tank dive day along with the firmware version on my cobalt.

Any other information that you'd like me to post on the dives that would help??

Thanks !

John

 

[GMScuba]

Hi RonR,

I got my Cobalt back in March and I love it. Awesome computer. The other divers that I have been with have seen it and are amazed by it. My instructor is even buying one since he saw mine in use and saw how easy it is to work with. However, this past weekend while working as a DM, I have a complaint. Actually more of a feature that can be improved. The problem is the fact that when you come to the surface longer than 2 minutes, the Cobalt wants to end that dive. Now it isn't abnormal for me to be accompanying a student and we come to the surface for a couple of minutes, I explain something, and then go back down. Unfortunately, this is very bothersome when trying to log a dive in a classroom setting. Would it not be beneficial to be able to increase the amount of time before the computer starts a new dive? For some people 2 minutes is just fine, however I'm pretty sure that 2 minutes is just too short of a time for other people as well. On my old Aeris Atmos AI, it didn't start a new dive until after a 10 minute surface interval. Is there a possibility to be able to change that setting in a future firmware update? It would be great if there is an option in the Settings to where a user can modify the time before the Cobalt starts a new dive. Another neat feature would to be able to combine two dives if in fact you come up for 3 minutes to do some minor instructions and then go back down. For instance, on CESAs, when an instructor brings a student to the surface, it might take longer than 2 minutes to explain to the student what all he/she did wrong and ways to improve upon their technique.

 

[RonR]

Hi RonR,

I got my Cobalt back in March and I love it. Awesome computer. ....<snip> Would it not be beneficial to be able to increase the amount of time before the computer starts a new dive? For some people 2 minutes is just fine, however I'm pretty sure that 2 minutes is just too short of a time for other people as well. On my old Aeris Atmos AI, it didn't start a new dive until after a 10 minute surface interval. Is there a possibility to be able to change that setting in a future firmware update? I....<snip>

I understand the issue with the two minute surface interval, particularly for instructors. There is a reason for it though, it's not arbitrary. The interval between dives is defined by the algorithm, and by extension, the physics of bubble formation. After you have been at the surface for two minutes, the algorithm will treat any re-descent as a new dive, which will have repetitive dive factors added, and have shortened no-stop times. The time at zero depth with quick re-descent is an additional risk factor for DCS, as there is time for seeds to expand,but not time for re-absorbtion or off gassing. Since the algorithm treats this as a new dive, we mirror that in the display.

However, we have tried to mitigate the irritation value by preserving the dive screen, along with any compass bearings, for five minutes of continuous surface time. We plan to, in a future firmware update, offer the ability to merge/ link dives in the log, so instructors don't end up logging 8-10 dives on what was really one pool session. Hopefully this will go at least partway towards what you want, unfortunately the two minute barrier for starting a new dive is not likely to be changed- that requirement is coming from the algorithm developer, not from us or Atomic.

Ron

 

[citycountryguy]

I have a question that I probably should know the answer to already, but I don't...Is the quick release mechanism for the Cobalt proprietary, or will it work with other air integrated computers that also have a quick release mechanism? I'm going to lend my daughter my reg, and she has the Oceanic ProPlus 2.1 with quick release, while I have a Cobalt. Do I need to change the hose, or can she just use what is there?

 

[RonR]

I have a question that I probably should know the answer to already, but I don't...Is the quick release mechanism for the Cobalt proprietary, or will it work with other air integrated computers that also have a quick release mechanism? I'm going to lend my daughter my reg, and she has the Oceanic ProPlus 2.1 with quick release, while I have a Cobalt. Do I need to change the hose, or can she just use what is there?

The Cobalt's system is a custom one- for actually some very good reasons. You can change either the entire hose, or just the end part that is the female QD connector- it will thread onto any standard HP hose.

Ron

 

[master_diver_UJ]

Can you give some more information as to the dive profiles, and firmware version of the Cobalt?

Dives shallower than 40' won't necessarily trigger a safety stop, it's not just a mechanical process on every ascent, as it is on some dive computers. We use an algorithm for determining the need for a safety stop- for divers who are bouncing around in the 39' to 15' zone, we don't want to be constantly generating safety stop alerts. And when your dive is that shallow, the safety stop is a non issue as far as actual safety is concerned. In effect, it would just make your dive longer.

If your subsequent dives were deeper than 40' and didn't generate a safety stop, that would be something we would want to look at further.

Ron

Hey Ron:

Ok, here's the information you had asked for. Firmware version on my Cobalt: v.1.41/2.

Three tank dive stats from May 6, 2013. A disclaimer of sorts - the dive profiles are a bit wonky, but this was a day of guide led shark diving in Costa Rica:

Dive 1.
Dive start time: 9:42am
Dive length: 49 minutes
Max depth: 86 feet
3 minute safety stop routine initiated by my Cobalt
Surface interval: 46 minutes

Dive 2.
Dive start time: 11:16am
Dive length: 53 minutes
Max depth: 59 feet
3 minute safety stop routine not initiated by my Cobalt
Surface Interval: 1 hour 18 minutes

Dive 3.
Dive start time: 1:26pm
Dive length: 51 minutes
Max depth: 73 feet
3 minute safety stop routine not initiated by my Cobalt.

Let me know what you think, Ron.

Thanks !

John

 

[RonR]

Hey Ron:

Ok, here's the information you had asked for. Firmware version on my Cobalt: v.1.41/2.

....
John

John,

This certainly looks like you should have seen a safety stop alert, with the countdown timer appearing around 25' depth. I will run some tests tomorrow to approximate these profiles- if you have downloaded these dives would it be possible to send the files to us?

Thanks,

Ron