Suunto Zoop v Cobra

[JohnN]

His original question was never addressed in the first place.
That comment of yours goes both ways.

You are correct. I became fixated on his perceived 'bargain' and misperceptions about what a LDS can do about manufacturers warranties.

Apologies to you and the OP for this

Both the Cobra 1 & Cobra 3 tracks your remaining air time. So to your question, yes, it will tell you an estimate of X minutes remaining at your current breathing rate.

So now you've got my curiosity piqued. The time remaining on a tank is a function of the air remaining and your air consumption rate. For any individual, that consumption rate is a function of your SAC and your depth. (lets dismiss increased consumption due to panic/exertion) So the time remaining on a tank will depend on the upcoming (not past) dive profile. I know those Finn's are a clever bunch, but exactly how does any computer predict what your will be doing?

 

[vladimir]

So now you've got my curiosity piqued. The time remaining on a tank is a function of the air remaining and your air consumption rate. For any individual, that consumption rate is a function of your SAC and your depth. (lets dismiss increased consumption due to panic/exertion) So the time remaining on a tank will depend on the upcoming (not past) dive profile. I know those Finn's are a clever bunch, but exactly how does any computer predict what your will be doing?

It calculates your current SAC (previous 30-60 seconds) and tells you how long your air will last at that rate and at the current depth. They (those clever Finns) assume that a certified diver will know that ascending will extend that time and descending will diminish it. It factors in a reserve of 35 to 50 bar, depending on SAC. So a diver with a low SAC will have 35 bar remaining in his tank when the remaining air time equals zero.

 

[taucherguy]

I personally have the Suunto Cobra and like it. I hate to distract you from the Suunto here but if I were to replace it, I would go with an Oceanic VT4 or similar.

 

[JohnN]

It calculates your current SAC (previous 30-60 seconds) and tells you how long your air will last at that rate and at the current depth. They (those clever Finns) assume that a certified diver will know that ascending will extend that time and descending will diminish it. It factors in a reserve of 35 to 50 bar, depending on SAC. So a diver with a low SAC will have 35 bar remaining in his tank when the remaining air time equals zero.

Thanks, makes sense. Sounds like a compelling argument for ignoring this 'feature'. To safely conclude your dive, you're going to need to guestimate how much air you need to make it to your safety-stop plus whatever cushion you are comfortable with (including potentially taking care of your buddy). I just don't see where this can help you that much.

For example: 5 of air on the computer @ 100' is entirely different than 5 minutes of air at 25' (and yes I understand you're minutes of air will increase as you ascend)

 

[DitrasetMan]

As a new diver, I am still not settled as to whether I will use these extra features in the Cobra over the Zoop. I am just not sure if it is worth the extra $233.

 

[RonFrank]

This would be from an AL authorized shop. I am not a fan of buying things on the internet for scuba.

Any thoughts on the actual tech differences for a new diver who will be only using them less than 100 feet.

LOL! I not only buy online I have my gear serviced online as well. The difference is I am not driving an hour one way twice, and its half the price. They do a great job, and send me my original parts so I can inspect them for wear and determine if my service intervals are too long/short.

Both computers are Suunto and use the same decompression algorithms. You pay more for the AI, digital compass and maybe a newer model. If that is important to you then..... They both will work to depths deeper than you want to dive.

Suunto uses very conservative algorithms which I find the whole varying conservatism thing pointless, and they are already more conservative that most.

---------- Post Merged at 03:54 PM ---------- Previous Post was at 03:09 PM ----------

Thanks, makes sense. Sounds like a compelling argument for ignoring this 'feature'. To safely conclude you're dive, you're going to need to guestimate how much air you need to make it to your safety-stop plus whatever cushion you are comfortable with (including potentially taking care of your buddy). I just don't see where this can help you that much.

For example: 5 of air on the computer @ 100' is entirely different than 5 minutes of air at 25' (and yes I understand you're minutes of air will increase as you ascend)

There is no guessing. When you get to 15' it will tell you if you have the necessary gas. If not you will be going into your reserve or ending the dive early. If you are using you gas up prematurely it will be beeping at you.

An AI computer does the calculations for you. You can set your reserve, it does the rest regardless of errors you could make or how narced or confused you get. Just do not shut down the audible alarms and wonder why it never alerted you.

I dive an AI computer and they are very nice. Your remaining air is calculated and expressed in time, so you have 5 minutes at 100', rather than 1250 psi which is more abstract. Plus you remaining time may be based on NDL or gas and the computer shows the lowest time. This is based on whatever is most critical. You can display any of the values, but if your just diving on remaining time your good. If your not paying attention you will still do the correct thing as long as you follow the computer which is how most of the world dives.

While many in the scuba world make the argument that technology = bad, I feel technology = great. Are brass gauges better? My brass SPG is off vs my digital SPG which is correct (verified via the LDS, multiple commercial SPG's). My brass SPG reads approx 200 lbs less than what I have... not good but I know this.

I like my AI SPG for many reasons. One gauge, everything on one readout, easy comprehension, why do I want multiple devices to check when one has everything I need? The Luddites will disagree but for the rec diver the AI computer works. I do carry a backup SPG and puter but the SPG stays in my dive bag.

 

[slugdiver]

Bit of past history. My first computer was the Orca Edge. Graduated to the Skinny dippers.
Recently bought used gear and it had a Sherwood Source mounted. I thought to myself, "What a piece of crap." But guess what? I absolutely love it now because it closely mimics the Edge graphic display.
My point is this, in my mind there is great value to having a graphical display (tissue loading bars) of NDL. A quick glance and I have the crucial info I need. So few computers have this display.
So I went and bought a Genesis React Pro. Love it too. Least expensive, but most feature-rich computer I found.
My advice? Look around. Don't be swayed by brand or price, buy what you are comfortable with.
And what is it with the 100' comment? If you don't break that by your tenth dive I would be surprised.

 

[Willar]

Yes, the Cobra shows Air Time Remaining in minutes based on your current dive air consumption rate and current depth, assuming you surface with 700psi. If you move shallower you will may see the air time remaining actually increase. I found this really handy as a guideline as a new diver but I don't follow it as much anymore, I read the pressure more often than ATR. But I still like the feature.

As far as the price, if it is the Cobra (1) and not the Cobra 3, you are paying about $100 for the analog compass and $130 for the computer. I REALLY like the analog compass over an electronic one. Having a good compass, and the Suunto SK7 is one of the very best, is a great thing on almost every dive. After having the Cobra/compass combo, I would not enter the water without a good compass as I use it very often to check my bearings and maintain in my mind a picture of the site and my position. The remaining extra $$ for the Cobra are for the backlight and other added capabilities.

To my mind, for that price, the Cobra and compass are a great deal compared to the Zoop Console.

 

[DitrasetMan]

As far as the price, if it is the Cobra (1) and not the Cobra 3, you are paying about $100 for the analog compass and $130 for the computer.

What did you mean by these prices?

I believe that $563 is a good price for the unit, but I would appreciate everyone's input.

I keep going back and forth. One thing that bothers me about the Cobra unit (as opposed to the Zoop unit) is not having a manual pressure guage. The thought of relying on a piece of electronics to tell me how much pressure I have in the tank worries me.

 

[vladimir]

The thought of relying on a piece of electronics to tell me how much pressure I have in the tank worries me.

This has been discussed in numerous threads. I am one of the early adopters of wireless AI, starting with US Divers Monitor 2 (or 3?) in the early 90s. The data transmission back then was typically interrupted on every dive. They have gotten progressively better as I've updated (Uwatec Air X, Uwatec Air Z, Suunto D9), to the point that I have never caught my D9 in a signal lapse. Strobes are the most commonly cited reason for data interruption, and I carry two on every dive.

When I go for a long weekend of diving I leave my glass-and-brass SPG at home. If I go for a week of diving I bring it, along with a spare computer. I don't bring them to save a particular dive, but rather the next day or days of diving.