First Dive Computer

[Jewls]

Hello All,

I have decided that I am going to pursue more diving adventures and am ready to start saving and investing in some scuba equipment. Right now I have the basics (mask, snorkel, fins) and am seriously considering a dive (wrist) computer as my first piece of major equipment. I have been doing a bit of research here and there on the different brands and what they have to offer. Considering that I’m new to scuba, I would really like to keep it under $300. I kind of have my wish list already, but don’t know if I’m going to find all these things in a $300 computer……

fresh / salt water
cold / warm
altitude
NDL
Ascent rate
Depth
Nitrogen levels
Compass
Backlight (for night dives)
Logged dives
I know some have the air source integration, but those are way out of my price range right now, although that would be a nice a back- up if I could find one in my price range (doubtful :depressed

I have been looking at the Cressi Archimede II, seems to have most of what I want minus compass and air source intigration.

Any suggestions, tips or advice for a first time dive computer whether it's the Cressi or another brand or just things I should look for in a computer would be really helpful.

 

[scubamarketing]

Most computers will have all of those features, the compass is the one that's a bit more specific and can boost the price. Here's a link to several wrist style computers with a compass: Computers | Dive Computers at LeisurePro.com

I've personally used Suunto for the last several years and I love it. Some people say their algorithm is too conservative, but I can manage my air better than anyone I dive with, so my calculated bottom time isn't a big concern for me.

Let me know if you have any other questions I can help with!

 

[Bubbletrubble]

You listed "nitrogen levels" as one of the features of dive computer. The ones I've seen have a green-yellow-red visual system to represent nitrogen loading. NDLs (no deco limits) take nitrogen loading into consideration. A separate nitrogen level read-out is redundant. FWIW, no dive computer actually measures "nitrogen levels" in the body. The "level" is calculated according to a deco algorithm using current dive profile data (time, depth) and previous nitrogen exposure.

Some people like air-integration. Some people don't.
If you're on a budget, I'd recommend buying a simple dive computer (non-air-integrated) in addition to an analog SPG and separate compass (Suunto SK-7).

The Archimede II is a wrist computer. That's my preference. Some advocates of console-mounted computers cite the convenience of having all critical dive information in one place. Personally, I haven't had an issue with keeping the compass and computer on my wrists and the SPG clipped off on the left waist D-ring. Find out what system works best for you.

If you have a hard-to-fit body type, I'd recommend purchasing a wetsuit before a dive computer.

 

[DiveNav]

Start here: How to Choose a Dive Computer - FREE Online Class

 

[Jewls]

You listed "nitrogen levels" as one of the features of dive computer. The ones I've seen have a green-yellow-red visual system to represent nitrogen loading. NDLs (no deco limits) take nitrogen loading into consideration. A separate nitrogen level read-out is redundant. FWIW, no dive computer actually measures "nitrogen levels" in the body. The "level" is calculated according to a deco algorithm using current dive profile data (time, depth) and previous nitrogen exposure.

Bubbletrubble - as I am still learning about dive computers and what they have to offer, the Cressi Archimede II states "The new software analyzes the data of 12 sample tissues (previously 9) for even more accurate monitoring of tissue saturation and de-saturation mechanisms." Do you know how this process works? How do they obtain the sample tissues? Is this from the diver or is this maybe from a study they used in order to create the "estimated" nitrogen levels?

If you have a hard-to-fit body type, I'd recommend purchasing a wetsuit before a dive computer.

I forgot to mention that my basic equipment includes a 3 mm shorty and 7 mm long wetsuit. Unbeleivably I purchased both for under $50

 

[The Chairman]

One of my faves that fits your budget is Ocanic's Veo series. Way easy to use and very reliable.

 

[Stu S.]

The Cressi is a good computer. That and some others are made by the Seiko watch people. Oceanic/Aeris is a good one, with a more liberal algorythm that should calculate more bottom time. (some may say less safety)

Computer compass? Many of us prefer the compass on a little slate or by itself. For me, a wrist compass will say North is my steel tank. For true reading, I prefer to hold the compass further in front of me than wrist mounting allows. It also is in better focus for a guy my age.

 

[Jewls]

Computer compass? Many of us prefer the compass on a little slate or by itself. For me, a wrist compass will say North is my steel tank. For true reading, I prefer to hold the compass further in front of me than wrist mounting allows. It also is in better focus for a guy my age.

Interesting fact, I hadn't thought of the magnetic pull from the tank effecting the direction of the compass. That’s good to keep in mind and I am now considering the compass as a separate piece of equipment. We used a compass on a slate with top and side reading for my open water certification. It was very easy to use. I think this might be the best to go…at least for me.

 

[mitsuguy]

"The new software analyzes the data of 12 sample tissues (previously 9) for even more accurate monitoring of tissue saturation and de-saturation mechanisms." Do you know how this process works? How do they obtain the sample tissues? Is this from the diver or is this maybe from a study they used in order to create the "estimated" nitrogen levels?

Without getting too deep into decompression theory, all decompression models have somewhere between 6 and 14 theoretical tissues... There is no proof that more = better, all models appear to work just fine... Each theoretical tissue has its own half time (the rate at which that tissue absorbs and offgasses nitrogen), and its own M-value (the maximum nitrogen level for that tissue). Most models are based on RGBM, Buhlmann, DSAT, the US Navy, or one of a few others, and sometimes they are bastardizations of one of the above or combinations even...

The Cressi stuff is pretty nice stuff... You should also look into the Oceanic lineup - the new VEO and GEO series are pretty nice - most allow the option of two different algorithms, as well as conservative factors. Suunto makes a nice computer as well, but in comparison, it is much more conservative than all of the others out there. While other computers can be used more conservatively, Suunto can punish you for not.

 

[Jewls]

Without getting too deep into decompression theory, all decompression models have somewhere between 6 and 14 theoretical tissues... There is no proof that more = better, all models appear to work just fine... Each theoretical tissue has its own half time (the rate at which that tissue absorbs and offgasses nitrogen), and its own M-value (the maximum nitrogen level for that tissue). Most models are based on RGBM, Buhlmann, DSAT, the US Navy, or one of a few others, and sometimes they are bastardizations of one of the above or combinations even...

The Cressi stuff is pretty nice stuff... You should also look into the Oceanic lineup - the new VEO and GEO series are pretty nice - most allow the option of two different algorithms, as well as conservative factors. Suunto makes a nice computer as well, but in comparison, it is much more conservative than all of the others out there. While other computers can be used more conservatively, Suunto can punish you for not.

Thanks Mitsuguy, this does give me a general impression of what they mean by "tissue samples" and how they estimate the nitrogen intake and release. If you don't mind me asking, what exactly do you mean by

Most models are based on RGBM, Buhlmann, DSAT, the US Navy, or one of a few others.

(Sorry if this should be known, but that's kind of why I posted the thread, to learn more about this stuff )