looking for my first dive comp

[Tbar]

What if you're a regular woman with a decent SAC (as even new diver women often do have), diving a typical reef profile and you happened to rent a 100?

Your buddy will be low on air...

You will reach the dive operators max dive time...

Rent a smaller tank it will be more comfortable

(note you describe my dive buddy, smaller, experienced woman, she dives with an appropriate tank)

We use Mares Puck computers and don't find a limit due to NDL on 'normal reef' dives, we have just done a live aboard, 21 repetitive dives over 7 days, most days were 4 dives, typical dive time 60minutes, and this was the limit set by the dive operator.

 

[Nicole Chan]

There is no service except battery change. The only "after sales service" issue I can think of is, in the very unlikely event that it breaks during warranty, who pays the shipping back to the manufacturer for repairs: you or the shop you bought it from.

I don't suppose it's the amphos air model for under $360? -- that would be a better deal in case you decide to add air transmitter later.

In the US at this point the cheapest options are mares puck, cressi leonardo, suunto zoop (but that one doesn't even have a gauge mode), or the last of aeris a300s on amazon (if there's any left) -- all in the $150 - $200 range. I don't know if you can get them where you are for that money.

Hi! The suunto vyper here costs about the same as the oceanic and sherwood. Would you recommend i buy from an authorized dealer abroad where it will most probably cheaper? Would i have any problem along the way? The only issue with oceanic here in the Philippines is the slow requisition of parts in case something breaks down. I saw the sherwood online for $260 though.

 

[Nicole Chan]

So you want to buy a new computer?

Yes. Well, it does not have to be brand new if i can get a good deal where i'm from

 

[Nicole Chan]

Hi Nicole,

The Sherwood Amphos runs the DSAT decompression algorithm, basis for the PADI RDP. The Oceanic Geo 2 runs DSAT and PZ+, a proprietary version of Buhlmann ZHL-16C, somewhat more conservative than DSAT. I dive a Geo 2 as a backup to my VT3, running DSAT.

Mares , Suunto, and Cressi all run proprietary versions of RGBM decompression algorithm and are generally more conservative. Mares and Suunto appear to run similar to PZ+, Cressi is the most conservative of the group. Many divers prefer a more liberal algorithm, particularly when their initial air consumption improves to the point where NDL makes a difference compared to air consumption. I believe dmaziuk dives a Cressi, his air consumption must make NDL less of a consideration. This debate has been played out in numerous computer threads on SB

If I were you, I would go with the Geo 2.

Best of luck, good diving,

Craig

Thank you Craig! I think the Oceanic would be great too especially down the road if i will end up getting a more sophisticated one at least they would "match"

 

[Tbar]

Yes. Well, it does not have to be brand new if i can get a good deal where i'm from

So you want to buy a new computer?

I am not sure you are aware, this was a link posted than may give more information on computer 'features'.

 

[Nicole Chan]

So you want to buy a new computer?

I am not sure you are aware, this was a link posted than may give more information on computer 'features'.

oh yes, i read this already.

 

[stuartv]

Your buddy will be low on air...

You will reach the dive operators max dive time...

Rent a smaller tank it will be more comfortable

(note you describe my dive buddy, smaller, experienced woman, she dives with an appropriate tank)

We use Mares Puck computers and don't find a limit due to NDL on 'normal reef' dives, we have just done a live aboard, 21 repetitive dives over 7 days, most days were 4 dives, typical dive time 60minutes, and this was the limit set by the dive operator.

I have rarely been limited by my buddy getting low on air.

I have never had to end a dive because of hitting an operator's time limit. Operators in the Outer Banks don't give a time limit that I'm aware of and the operators I've gone out with in Hawaii were chosen, in part, because they specifically allow their customers to dive their tank - even the ones like me that rent a 100 or a 120.

I have done a number of dives (of my limited number, total) where I was able to stay down until the NDL of my liberal computer - and my buddy with me. I HAVE had to end dives earlier than my computer required because my buddy had a Cressi computer that gave a shorter NDL.

Your liveaboard experience suggests that maybe your dives tended to have average depths closer to maybe 60 feet or less, where NDLs are longer and an AL80 also lasts longer. Some people (me, for example) more normally do dives in the 100+ foot range where NDLs are short, even on Nitrox, and it's not that hard for even a plus-sized man like myself to outlast the NDL, even on a liberal computer - especially if using any size tank that is larger than an 80.

 

[stuartv]

In general, it seems like I often see posts recommending to new or new-ish divers to buy a computer based on their current needs. The needs of new and new-ish divers is on the steepest part of the curve. Their "needs" are likely to change more in their next 20 dives than they will after they are more experienced.

Why would anyone think it's a good idea to recommend buying what is good for today and ignore what you could very likely want in 6 months or a year? Sure, don't worry about buying a tech computer today if you're just starting out. But, it does seem like a smart thing to do to buy based on what you anticipate your needs to be in 6 months or a year. Or in, say, the next 20 - 40 dives.

 

[gopbroek]

Depending upon the type of diving you do, NDL times can become an issue very quickly and it might be a good idea to allow for flexibility from the start. As an example in low stress drift diving such as Cozumel (where ideally you drift along trimmed out and expend as little energy or air as possible) it is not uncommon to get times of 70 - 80 minutes off of AL80's and if you are attempting to do multiple dives a day after multiple days you may run into issues with a Pz+ or RGBM algorithms. The DSAT algorithm seems to be one of the more liberal algorithms available on a lower end computer. I run an Oceanic on DSAT and Nitrox and I still need to limit my diving to keep it happy over a week of diving.

In a more stressful and physically demanding type of diving it is doubtful that you would achieve these types of times but regardless I would probably want a little more conservative algorithm such as the PZ+ as an extra safety factor.


If you have access to Amazon here is a cheap (orphaned but warranty still honored by Oceanic) dual algorithm (PZ+ & DSAT) unit that should be good from beginner to beginning tech.

Amazon.com: Aeris A300 Wrist Computer ~Includes now FREE the Digital online class to get the most out of your dive computer.: Sports & Outdoors

 

[dmaziuk]

Some people are not obsessed with NDLs, but nevertheless would prefer to have longer NDLs, so that they can enjoy more time actually diving. Are you suggesting that the new diver OP should start doing deco dives as soon as she is at the point where she her dives are no longer being limited by the gas she's carrying?

What I learned so far is the longer you stay down below, the more gas gets into your tissues. The more gas you have in your tissues, the longer it takes to off-gas. The difference between NDL and Y(es)DL is

• NDL: you can slowly swim up all the way, but you really really should make an optional but highly recommended safety stop, and have a one in bazillion trillion chance of getting DCS.
• YDL: you can slowly swim up, but you must make a non-optional deco stop in order to keep your chances of getting DCS down to the same one in bazillion trillion.

To me it looks like the key in both cases is having enough gas for the stop. I would think, the chances of having enough gas for the stop would be better had one actually planned for it in the first place.

Aside from that, the way computers work is they periodically recalculate stuff. If you come up to depth X and see 2 minutes NDL: wait a few seconds and 2 may change to 99. If you come down to depth X and see 2 minutes, then you have a choice of staying down for 119 seconds or "blowing past" NDL and making your safety stop mandatory instead of optional. If you stay long enough at shallower depth after blowing the NDL, you may well find your mandatory deco obligation has magically disappeared from your computer screen.Etfc.

But like I said, that's just me -- if your definition of "better computer" includes bigger NDL numbers, that's NMP.