Off Topic -- slightly. Dive Computers

[Anton Lundin]

On 06 March, 2015 - Steve Butler wrote:

> Any updates to Linus' Dive Computer ramblings regarding the Cobalt2 and/or
> Eon Steel?  Other color, air-integrated DCs folks would recommend?
> 
> Wanita and I have been using Cobras for the last three years.  But we can't
> see the backlight at depth (or in our living rooms) and shining a dive light
> on it produces a lot of glare unless the angle is just right.
> 
> We've both had cataract surgery and I've had a detached retina repaired
> (yes, the surgeon specifically agreed I could dive).  Then there is
> something about four and three score orbits of Sol. Definitely want color
> and lighted.  Our experience at 120' last Sunday while narced convinced me
> we'll never dive deep with the Cobra as the primary DC again.  I'm even
> debating if I want to allow it as the secondary (note, I don't have a
> secondary now).
> 
> --Steve
> 
> PS  We'll finish our deep specialty after  the new DC is tested out.
> 

I'd thought i dump out some thoughts about DC's to.

I started out diving with a Suunto Vyper as my one and only DC, and it
worked pretty well. I like the big clear numbers on the display, and it
got a awesome battery time. But i don't like that you need to push a
button to get the backlight on and trying to do deco diving on it is
just plain stupid. Its actually pretty resonable up to 10 mins of deco,
and past that it just shoots away. We did some wreck penetration
training and doing gas sharing exits passing restrictions we got a bit
delayed, and the Vyper showed 65 min of deco. Subsurface calculates
the TTS based on the same dive to 15 min.
(One of the reasons i wrote that TTS/NDL code was actually to compare
it with the numbers from my Vyper)

I've only seen extensive use of Suunto Vyper/Vytec-series computers and
i haven't seen any of them fail for any other reason than the owner
botching a battery change and thus drowning the device.

I still carry that Vyper in my dry suite pocket as a backup computer in
Gauge mode. Its battery life is great for that.


As my main computer i use a OSTC3 nowadays. I've saw a bunch of them
fail to begin with but now with the replaced and fixed versions all the
ones in my diving team works like a charm.

It got great readability and i love how compact it is. I also like the
mecanical push-buttons better than the piezoelectric ones in the OSTC2
and predator/petrel. It doesn't do air-integration. It would be fun to
have the pressure-sensor data in subsurface for analysis but i don't
care for it during my dive. I don't mind unclipping my spg from my left
hip and looking at it to verify my mental model of what pressure I'm at.

I've done quite a bit of diving with the OSTC2N, and too is a great
computer, but i like the OSTC3 better. The layouts on the OSTC3 is
better and the menus are easier to comprehend.

I also got a OSTC Sport laying next to me here. Its almost the same
hardware as the OSTC3, but with a constrained firmware. I haven't had
time to test it in the water yet.

One big upside with HW computers is the HW team them self. They are just
awesome and have great support for their gear.


One other manufacturer to mention is Shearwater. In my dive team its a
30/70 split between Shearwater computers and HW computers. The Predator
was a great computer and the Petrel is a even better one. Its bulkier
than the OSTC3, and it has piezoelectric buttons. One upside is that you
can get them with fisher-connectors to run as your rebreather monitoring
device, which is way more hassle with the OSTC3.

I've seen some weird failure modes on Petrel's. One stopped accepting
any input at all, but looked fine in surface mode, and another lost half
of its menus. The support from Shearwater was just great, having there
English distributor over night ship a replacement device to Malta so my
mate could continue to dive was just great. It was kinda a show-stopper
when his Petrel died becase he was using that as his way of monitoring
his mCCR.



That kinda sums it up for me. I do technical diving, and don't care
about air integration so here's my 2 ören:

If i where in for a cheap option i would probably by a second-hand OSTC2.
There's a lot of them out there on the market and you could be lucky to
pick one up for the right price.
If i where going to by a new computer it would be a new OSTC3.


//Anton


-- 
Anton Lundin	+46702-161604