Petrel v. Vyper :)

[LowVizWiz]

I know a lot of people dog Suunto computers because they are conservative and everyone loves the Petrel. Even people with no aspirations of ever doing planned deco dives. I like them both for different reasons and applications and that's why I own both.
I have never been limited on recreational dives because of my computer and I have been diving with 4 different Suuntos for the past 9 years.

So with that said, I decided to do a little test and took them both down on a pair of rec. dives diving EANx .33 in which I would put my Vyper in deco for ~10 minutes and compare the Petrel (GF 30/85)

First dive The Capt. Dan ~120 to the sand, max depth 110', ave. depth 75', duration 51 min.:

The Vyper Air entered deco at the 25 minute mark (the sample rate is set to 60 sec. so it could have been closer to 24 minutes), I ascended slightly and continued to dive for another 10 minutes before initiating my ascent to the deco stop. At 20' the computer showed a deco obligation of 7 minutes. The NDL for a square profile to 110' on EANx 33 is 25 minutes according to the tables I have in front of me.


The Petrel entered deco exactly at 23 minutes and 10 sec. and after reaching the deco stop depth it showed a 7 minute obligation.



Dive two: After a 53 minute S.I. did a drift dive on the 3rd reef line with a max. depth of 57', avg. depth 45' and a duration off 66 minutes:

Vyper Air entered deco at 56 minutes which cleared while I leisurely reached the surface 10 minutes later.


The Petrel showed an additional 47 minutes of bottom time remaining after 56 minutes

Clearly the Petrel is more liberal than the Vyper when it comes to repetitive dives, but I wouldn't consider the Vyper profiles limiting by any standards.

So where does the hate for Suuntos come from?
Is it the computer or the way rec. divers want to dive their computers?

Fire away...

 

[Superlyte27]

It's not hate for Suuntos. It's admiration for Shearwater. The Shearwater is simpler to use, easier to read, impossible to outgrow and has the best customer support on the planet compared to any company in any industry ever.

Except for price, why on earth would anyone choose any other computer?

 

[LowVizWiz]

It's not hate for Suuntos. It's admiration for Shearwater.
Except for price, why on earth would anyone choose any other computer?

But people have been dogging Suunto computers way before the Predator or the Petrel were even around. Mainly because of this perceived extremely conservative and limiting algorithm.

 

[djtimmy77]

Probably because they do fast ascents and see-saw profiles and their NDL gets hammered by the Suunto. Also after maximizing the time on their first dive, being forced back into the water with a short SI so the boat can meet the schedule, the Suunto punishes them with short NDL.

 

[commitch]

It's not hate for Suuntos.

there's plenty of tech divers here that hate Suuntos.

Except for price, why on earth would anyone choose any other computer?

Because different divers have different likes. The Petrel doesn't do AI. Some love it, some hate it. The Petrel doesn't have audible alarms. Some like them, some hate them. Some people want crazy conservatism when they are doing 30 dives in a week. Others don't want the limitations of something like the Suunto algorithm when doing repetitive dives. It's all about what the individual diver paying their own money actually wants.

I get why people think Shearwater and their computers are awesome. I agree with them. I just don't get why people think they are perfect, even ignoring price.

 

[Dr. Lecter]

But people have been dogging Suunto computers way before the Predator or the Petrel were even around. Mainly because of this perceived extremely conservative and limiting algorithm.

Is your set of two dives really clearing up the issues with the Suunto? Try doing another dive later, or a set the next day, and see what happens. Also consider the fact that I can do more or less whatever I want with the Petrel, not just 30/85. Not so with the Suunto.

 

[victorzamora]

I'm one of the people speaking poorly of Suunto computers. Your data backs me up, actually. I'm not saying that the first dive is too conservative. I'm saying that repetitive dives get goofy on the Suunto algorithm. Not only do they get far more conservative within NDLs, repetitive deco dives get HARSHLY penalized. Unrealistically so, on some profiles. The conservatism for the Suunto isn't conservative, it's unrealistic. They get SUPER goofy under some scenarios, and I want a computer that can handle anything I throw at it and more. Suuntos work well under a very strict set of parameters, and start acting goofy outside of them.

The other point against Suuntos I have is that their proprietary algorithm makes them nearly impossible to match to anything else, and the ones with the stupid heart rate monitor are even worse because they're trying to account for stuff that no decompression studies have ever found correlation between....and they apply it seemingly randomly. With any other brand of computer, you can get close to others with some tweaking of conservatism. On Suuntos, they'll start out liberal and then swing heavily "conservative" for seemingly no reason.

As for AI and audible alarms: There are too many reasons to not have them. I can understand why people like them in theory, but in reality they just suck. Also, if that's the only thing keeping you from getting a Petrel, your priorities are WAY out of whack. Shearwaters are arguably the most reliable computers on the market, supported by arguably the best company on the market, with arguably the best screen on the market, and they can go above and beyond what nearly any diver could ever dream of doing.

 

[LowVizWiz]

Is your set of two dives really clearing up the issues with the Suunto?

That's exactly what I'm trying to find out.
The issue that people bring up all the time is how conservative the computer is during repetitive diving.
I realize my two dives don't represent every situation there is, but maybe you would agree that for a recreational diver these two profiles wouldn't be out of the norm for a day of diving and would not limit them at all?

Try doing another dive later, or a set the next day, and see what happens. Also consider the fact that I can do more or less whatever I want with the Petrel, not just 30/85. Not so with the Suunto.

I have done multiple days of diving with Suunto computers doing up to 5 dives in a day. Dives on the following day are not even an issue as far as I'm concerned.

Please, don't get me wrong! I'm not trying to knock the virtues of Sharewater.

My only point in comparing the two was that one is well liked and with plenty of reason, while the other seems to be a whipping dog because of some perceived limitation. Yet, on the first dive both computers gave similar bottom times and on the second dive the Suunto also provided plenty of bottom time on a typical recreational dive which is the intended target for the computer. And it's my experience that this also holds true over multiple days of diving.

It seems irrational IMO or I'm really missing something! I have more issues with the lack of support and really poor desktop software than the computer itself.

 

[JohnN]

. . . and the ones with the stupid heart rate monitor are even worse because they're trying to account for stuff that no decompression studies have ever found correlation between. . .

You sure you're not talking about $cubaPro ?? I'm a happy (recreational diver) Suunto owner and have never heard of this feature on their dive computers.

 

[sphyrnidus]

A nice way to tell someone....