39 replies to this topic

[annasea]

Which computer do you use and why? Also, what features are a necessity and what should be avoided?

TIA!

[PerroneFord]

I suggest diving without a computer for a while. That's my personal opinion.

As for diving computers, they are mostly all the same. Some have some important differences and I'll try to touch on those.


Things to look for:

1. Wrist mount (since you're going Hog)

2. Large numbers for Depth and NDL Time Remaining

3. A guage mode so if you ever move forward with your diving, you can still use it

4. Download ability to analyze your dives. And yes, you SHOULD be doing this.

5. User replaceable batteries. Surprisingly, most computers don't have this.

6. A decent backlight in case you do some night diving.


Most computers are programmed with the same algorithm as the tables. That algorithm is tried and true though it has some serious limitations in how it models the body. The Algorithm most use is called Buhlmann, and again this is what your dive tables are derived from.

There are some newer algorithms out there that take other physiological factors into account. Some of the more popular ones are RGBM and VPM. Very few computers use these more modern algorithms. I sought one out specifically. VPM is unavailable in dive computers except for some VERY expensive models.

Suuntos products use a modified RGBM algorithm. They also have user replaceable batteries, and all but the Gekko have download capabilites built in. The Vyper is one of the most popular models. DSS makes a nice wrist mount boot for it. It has a guage mode, and big numbers. It's also reasonably priced. When searching, it was one of only 3 computers I found viable for my needs. But you need to assess your own needs.

Scubapro have a couple of nice computers. I don't care for most of the others for various reasons. Gregg uses the VR3 which is great if you want to spend $1200.

Others will have varying opinions and most people will tend to recommend what they have. Consider the features, drawbacks, and how "future-proof" the computer you will purchase is. Then spend your money and enjoy!

-P

[shadragon]

I have an Oceanic VEO 200 wrist mount I got on sale at my LDS. Had a $599 CDN pricetag, I paid $350, 18 months ago. It was an older model so I got it cheaper.

Specs here...

Decent rec computer with up to 50% EAN. Only handles a single gas. Downloadable data into my PC so I can see my dive profiles like this...

I have had it on 50+ dives with no issues. My only bug with it is it has three ascent measurements. 0 - 20 FPM, 20 - 50 FPM, and >60 FPM. Would love to see it more granular, but it has served me well. Stores about 25 dives in memory @ 10 second intervals. I set mine to 30 seconds and have lots of dives on there (Did the Red Sea for a week with no trouble). Auto "on" in water (selectable) and auto-off to save power. Comes with 24 hour FLY clock countdown. Has a backlight with user set time to turn off, you change the batteries yourself (They are available in my local drug store for about $7 each. Bit tricky. You have to change it out in 5 seconds or less or lose your stored dives. Battery hatch is also a little finicky to put back on.), big numbers, gauge mode and both audible / visual alarms if you do something silly. Shows N2, O2 loading with ascent descent rates and you can set your PO2 threshold to whatever you like.

USB interface cable for the PC runs $99 more. Software is available for a free download on their web site.

Does everything I need it too... Note: I am staying on the rec side of diving. If I were to consider tech diving I would have to upgrade. This is a general purpose recreational dive computer. I give it an 8 out of 10.

[Penguin]

I personally dive with the Suunto D9. It has 3-gas ability and gauge mode as well. One of the primary reasons that I originally bought it was because of the sending unit and therefore the ability to eliminate one hose from my equipment.

The Good-
--I love being able to eliminate the additional HP hose
--Although the wrist unit is slightly larger than a watch, it also doubles as a watch and I can wear it everywhere I go on dive trips--and do.

The Bad-
--Numbers are smaller than other computers. I have excellent vision so it is not a factor for me but certainly is for other divers.
--When doing shutdown drills, the unit WILL NOT pick up the tank pressure once the air is turned back on.

I also Dive with a Suunto Cobra. My personal preference is to keep the branding the same so that the underlying algorithms match one another. Personally, I prefer a back-up computer for safety reasons but also when on a liveaboard or week-long dive trip I do not want to lose any diving in the event of a computer failure. I find the additional cost for a secondary unit small in comparison to lost dives--especially if travelling to do the diving.

Like most any other piece of primary equipment, it is user-prefrence. Most everything on the market these days is high quality, it just comes down to what you prefer for the type of diving that you do and how much you want to spend. Like your investigating the used reg issue, you are doing the right thing by gathering information and making an informed decision as to what will meet YOUR diving needs.

[cmt489]

I dive with the Suunoto Cobra. It is not a wrist mount and replaces your depth gauge and pressure gauge on your octopus. It also has a compass that is specifically designed to fit onto it. My batteries have lasted several years and almost 100 dives and are still over half their capacity. I am very happy with it.

The draw backs are:

1. If you want a wrist mount this is not the computer for you; and
2. They are expensive.

[Geek]

We had a long thread on this once before. While Perrone and I were pretty much on the same page with regulators, we have a couple differences of opinion on the computers. Note that this isn't one of us being right and the other wrong, just a difference of opinion among home shoppers. These differences may seem minor to some readers, but we wound up going round and round last time.

Basically I agree with most of his criteria above, but I differ in opinion as follows:

Perrone likes to download his data and that is an important feature to him. Not everyone does this. If you care about this feature, then it will limit your model choices and you will pay a bit more, but if you aren't going to use this feature then I would drop it. Also note that the download kits are generally an extra cost accessory and don't come with the computer.

Perrone encourages doing without for awhile. I suggest, purchasing an inexpensive nitrox computer, with a gauge mode. An air only computer will not save you much vs. the nitrox computer. Also a computer of this type will not cost much more than a bottom timer, and you do at least need a bottom timer.

This level of computer will serve a new diver well for a number of years. While you may eventually need features included in some of the latest whiz bang models, it is unlikely that you will need them soon and computers are a rapidly evolving technology. Today's $1000 model may cost $300 in five years. In addition, if you get to the point that today's high end features are what you need, you'll also need a back up and the low end model can often serve as an adequate backup, particularly in gauge mode.

Note that my advice here is different than my advice on regulators. With regulators, I recommend that you get top quality. The regs are life support and the technology changes rather slowly. With computers a failure will mean abort the dive, not your life is in danger. Also the technology is changing rapidly and technological obsolescense is likely to occur within a few years no matter what you buy. Why spend a lot on something that will need frequent replacement?

The one other feature I would tend to emphasize is the screen. For some of us "visually challenged" divers some of the screens are hard to read. Make sure that whatever you pick you can read the display.

Edited by Geek, 22 March 2007 - 10:39 AM.

[dustbowl diver]

I purchased an Aeries Atmos2 a couple years ago for around 350. Geek is correct in that the down load cable was an extra $50. While a wrist mount, it has air and EAN capabilities. I think the display is easy enough to read. What Scuba Toys locally allowed me to do was rent a couple on some excursions to see what I liked best-perhaps your local dive shop will do the same for you!!

[Moose]

I purchased an Aeries Atmos2 a couple years ago for around 350. Geek is correct in that the down load cable was an extra $50. While a wrist mount, it has air and EAN capabilities. I think the display is easy enough to read. What Scuba Toys locally allowed me to do was rent a couple on some excursions to see what I liked best-perhaps your local dive shop will do the same for you!!

I also ended up buying this model. I'm not really happy with it. It's not that intuitive. Also, there are only 2 buttons (instead of 3), and it seems like it's always a pain to get where you want to be with it.

In a year or two, I will replace it. I'm holding out for a heads-up display in the mask! (Hopefully it will be at BTS this weekend!

[nydiver]

In a year or two, I will replace it. I'm holding out for a heads-up display in the mask! (Hopefully it will be at BTS this weekend!


It will be, both Oceanic and Aeris (basically the same company in the end) will be displaying the same heads up unit. Its OK, nothing overly special, does not have the capability of having perscriptions (while not needed for the nearsighted of us to read the headsup info, people with bifocals for reading will hate to try and read it), Also the proto we had the display was "annoying", it really got in the way after a while, and you needed to keep hitting the button to scroll to see all the info you wanted. Eventually they'll get it perfected, just not yet. Also as I understand it it will be a while before there is a HUD competitior, Patents were filed for the idea of a HUD in a dive mask and are working thru the court, results are favorable.

[PerroneFord]

A number of good point have been raised here, and I wanted to comment and clarify (and pose a question) so here goes....

In response to Geek's points:

I wanted or needed a computer that downloads because I do not do a paper log. This this feature is crucial to me. I know some, like Walter, prefer narrative on paper. I put important info in my online log, and that's good enough for me.

I encourage divers to do without a computer for a while to develop comfort diving without one. Any diver should be able to continue a trip or even a dive, without a computer. It's electronic, and it CAN fail.

Geek mentions that technology is ever evolving. This is true. Which baffles me when people talk about buying a new computer based on tables that were outmoded 30 years ago. Regardless, if your computer is guage mode, you don't really need anything other than a set of tables to dive on the newest algorithms. This is precisely what I do. I build my dive profiles at home, but bring my palm pilot with me in case I need to modify something before I hit the water. That way, a computer failure underwater has no bearing on whether I can complete my dives safely. For a recreational diver, if the computer fails, thumb the dive, make your safety stop at 15ft (use your buddy for reference) and exit the water.

He and I both agree on not spending a load of money on a whiz-bang computer. The ONLY exception I would give in to, is if you're on CCR. If you are, you know why.



Moose's comments:

I have seen some info on the HUD mask. My questions are:

1. Can you replace the lenses with prescription ones without losing the HUD?

2. If the mask fogs, does the HUD fog?

3. If you flood your mask, do you lose all your info? You certainly wouldn't be able to see it?

4. Does it dim for night diving?



A question for Penguin:

I have often seen divers talk about wanting to rid themselves of an extra hose, so the idea to go wireless seems appealing. Frankly, I wouldn't know my HP hose was even attached based on how my gear is configured. So my question is, what is so bothersome about having an extra hose? And could it be mitigated by simply reconfiguring how you store your hoses?


Thanks,

-P

[nydiver]

1. Can you replace the lenses with prescription ones without losing the HUD?

NO

2. If the mask fogs, does the HUD fog?

In a word, Yes, the HUD is imbeded in the glass plate in the version we had


3. If you flood your mask, do you lose all your info? You certainly wouldn't be able to see it?

The info doesn't get lost, but it would be like trying to read a dive watch in the water with no mask from 1 1/2" away

4. Does it dim for night diving?

Didn't see a way to "dim" it, but it wasn't that bright that it would be annoying, you just scroll till the display disappears.


I have often seen divers talk about wanting to rid themselves of an extra hose, so the idea to go wireless seems appealing. Frankly, I wouldn't know my HP hose was even attached based on how my gear is configured. So my question is, what is so bothersome about having an extra hose? And could it be mitigated by simply reconfiguring how you store your hoses?

So many rec divers are buying higher end computers, and with that usually comes a hoseless computer, one does not need to use the hoseless portion for the computer to function. Penguin may still use a guage for pressure with his hoseless computer if he chooses, but like many rec divers he chooses to use the hoseless portion. For many its handy, its downfall is that if the transmitter battery fails you lose the ability to read tank pressure and the dive will need to be aborted. To each his own, rec divers want gadgets and gizmos, but above all they want simplicity, they don't need tables that goto limits of testing, they don't need 3 let alone 10 gases available for tracking, they just need simplicity. Most of the rec computers are just that, simple, and contrary to your assumption many of the newer computers do not use outdated Buhlman tables, they have modified tables to try and stretch the limits also, just like your tables do.

You may not like it, but after OW, most students will not use tables, I have to imagine you have not been in a nitrox course with people who got cert'd at least a few years before, a DM class is the same way, its scary noone knows how to use the tables, Why? because they've been diving a computer since OW class and just plain never use tables, they do no pre-dive planning, they just listen to a DM and dive the general plan, putting complete faith in the computer. Is this a problem? Statistically it is not, there are less accidents these days with more active divers then there were before the advent of computers with a smaller number of active divers. Is it foolhearty to put complete faith in a piece of electronics, in my opinion it is and I know you agree, but reality speaks quite the opposite, the majority of rec divers put complete faith in their computer and that is the reason for buying the "Best" computer they can afford.

[Squishy Monkey]

I have an Oceanic VT Pro which is wrist-mount and hoseless. Personally I would NOT recommend going hoseless. My first dive on my first day on my first trip to the ocean and my transmitter goes out five minutes into the dive. We had to thumb the dive immediately. Thankfully the DM on the boat brought extra gear, so I was able to do the other 3 dives that day, using the the VT Pro as a non-air-integrated computer.

First thing I did when I got back from that trip ( and after getting the transmitter replaced) was to purchase an analog SPG to use as a backup. So I still have a high pressure hose coming off of my first stage.

I still dive that computer and have not had any more problems with the transmitter with the exception that it does lose sync sometimes and I have to hold my wrist close to the transmitter until it picks back up. When it comes time to replace, I am planning on using an analog SPG with a wrist mount computer that is not air integrated. It's really handy having the computer on my wrist, but I don't trust the transmitters any more. But that's just my opinion.

[Capn Jack]

Which computer do you use and why? Also, what features are a necessity and what should be avoided?

TIA!

Right now, I have two - because I just bought a new Cochran , and am donating the old one to my youngest.

I was very happy with my wrist mounted Aeris Atmos II - why and necessity are one list:
1. simple
2. Large display
3. Does Nitrox
4. User replaceable battery
5. Calculates and displays deco in case I screw up
6. Reasonable price ($300)

I decided to buy the Cochran EMC-20H (through OTWDiver) based on my experiences with it on the DAN study on two SD Trips.

Additional features to the above I needed to do the diving I have now decided to get into:
7. Switchable multiple gas
8. Upgradeable to Helium if I move on to trimix
9. Upgradeable to PPO2 if I want to sell it to a CCR diver

Since I'm looking at buying another set of O2 clean regs, redundant wing and a few other goodies, "reasonable" price for computer has also moved up. Contact OTWDiver for SD sweet deals.

Edited by Capn Jack, 22 March 2007 - 12:36 PM.

[Dive_Girl]

I was very happy with my wrist mounted Aeris Atmos II - why and necessity are one list:
1. simple
2. Large display
3. Does Nitrox
4. User replaceable battery
5. Calculates and displays deco in case I screw up
6. Reasonable price ($300)

The only draw back was no instructional booklet in German, right?

TAUCHEN!!

[Geek]

I wanted or needed a computer that downloads because I do not do a paper log. This this feature is crucial to me. I know some, like Walter, prefer narrative on paper. I put important info in my online log, and that's good enough for me.

He and I both agree on not spending a load of money on a whiz-bang computer. The ONLY exception I would give in to, is if you're on CCR. If you are, you know why.

I do keep a paper log, hence our difference on the download capability. You do a lot of diving, so I am sure you get value from that feature. My comments apply to the newbie diver who really doesn't know how much diving they will be doing or knows it will be a limited amount.

Speaking of whiz bang computers, I am looking for a multi-gas computer, so comments from those who own them would be appreciated. Last year there was a great sale on NiTek HE models that were being discontinued, but those seem to be gone. CCR's are a whole different discussion on which I am not qualified to offer an opinion.

I should also comment that I own a Sherwood Wisdom, which is great for those that find the displays hard to read. The display on the Wisdom is great, but I would not recommend the extra expense unless you really want that large display. I consider it a niche product.