How fast do prices go down?

[Shotmaster]

Almost everything I dive with is Scubapro. I cheaped out on a mask and bought a Cressi, man, that was a mistake. I really hate it. Once I can bring myself to pay $125.00, I am going to buy the mask I really wanted. I have done this a few times, and I always regret it. I think I am a Scubapro snob! Also, don't listen to the nay Sayers, I have a Luna with air integration, I really like it, you can disable all the beeps, it is highly configurable. I also have a Cobra 3, which I don't like, especially the menu functions. I have had a few others, like Uwatec Air, Nitrox. The Luna is by far the easiest to use and has a good screen and menu system. I like the Petrel, it has the best color screen but there is no air integration. The Petrel also uses a different deco model than Scubapro. Petrel will tell you they cater to the Tech divers and have no plans to add air integration. I know as I called them. It is a shame, I would buy one if it did.

 

[diversteve]

As soon as Shearwater adds a transmitter to the Perdix, then I think a fair comparison to the Galileo will show it to be the better option. Until then for what seems to be mostly recreational use - not so much.

 

[stuartv]

The Petrel also uses a different deco model than Scubapro.

Yep. The ScubaPro one factors in air consumption and heart rate into its deco calculation (according to the SP web page), if the sensors are there to provide it the data.

The Petrel's algorithm is published, peer-reviewed, and replicated in other computers and personal computer software. You can see what it does and compare it to other sources of info that use the same algorithm.

The SP algorithm is proprietary and varies its results based on data that no published or peer-reviewed algorithm that I know of does. You can't model what the SP will do using personal computer software. You can't compare it to any other source of information to figure out if it's working correctly or not.

As far as I know, every published deco algorithm says that heart rate and respiratory rate actually make no difference to inert gas tissue loading. So, I don't know what SP is doing in their computer, but I would not buy one, for that reason.

 

[boulderjohn]

The ScubaPro one factors in air consumption and heart rate into its deco calculation (according to the SP web page), if the sensors are there to provide it the data.

Do a search on the Ask Dr. Decompression forum for one or more of the many threads on the topic, and you will learn that air consumption rates have no effect on decompression. I don't know of any studies whatsoever that can tie heart rate to decompression profiles. It is true that a faster heart rate during the working, deepest portion of a dive aids in perfusion and ongassing, while a slower pulse rate during the decompression part of a dive lessens perfusion and thus offgassing, but I don't know of any study that has quantified this in any way that can be useful in determining a decompression profile.

 

[kelemvor]

The air consumption rate is used to calculate ATR (air time remaining). I don't know how the stuff would factor into decompression either, their site says this:
Integrated heart rate monitor senses your effort, incorporates it into the workload calculation, and then adapts the decompression algorithm.

I don't have the heart rate monitor, and for recreational dives (no deco, 130' or less) the NDL's have stayed very similar between my Galileo and my petrel computers on the occasions I used both. That combined with the thousands (or maybe millions?) of divers not dying with scubapro computers makes me not worry about trusting the deco calculations on a galileo. I'm not saying I'd use it for a technical dive (if I took that up), and I haven't used the galileo in a cave (that's why I bought shearwater). This person isn't doing tech diving though. I expect she'll be just fine with any computer she buys - including a galileo.

If she does take up tech diving, she'll probably buy all new gear anyway...

 

[kelemvor]

As soon as Shearwater adds a transmitter to the Perdix, then I think a fair comparison to the Galileo will show it to be the better option. Until then for what seems to be mostly recreational use - not so much.

Check out the Ratio ix3m. I'm pretty excited about it. It looks to me like it offers everything shearwater does plus a few things it was missing. According to @bhuranmuntasser they're going to release air integration soon. Also, I've seen a video of a rep saying it would get an he analyzer (along with the existing o2 analyzer). Both claim to be coming at the next DEMA. Of course, I've seen scubapro/seabear make claims about stuff coming out at dema, then seen it not happen....

 

[stuartv]

you will learn that air consumption rates have no effect on decompression. I don't know of any studies whatsoever that can tie heart rate to decompression profiles.

I thought that was what I said?

 

[CptTightPants21]

I thought that was what I said?

Your post has the stupid comment first and the smart comment dead last, can't blame people for not reading all the way through....I known I didn't

 

[kelemvor]

Your post has the stupid comment first and the smart comment dead last, can't blame people for not reading all the way through....I known I didn't

Why is it stupid for him to tell you what it says on a web page? It doesn't mean he's agreeing with anything, and is pertinent to the discussion.

 

[CptTightPants21]

Why is it stupid for him to tell you what it says on a web page? It doesn't mean he's agreeing with anything, and is pertinent to the discussion.

Yep. The ScubaPro one factors in air consumption and heart rate into its deco calculation (according to the SP web page), if the sensors are there to provide it the data.

Look how he worded the above. It's a declarative statement that implies agreement. His next sentence is talking about the Petrel. He doesn't talk about the SP again until the last paragraph. There are a lot of things he could have done to make it less ambiguous--remove the "Yep", or move the last paragraph to right below the line, among other things.

I read the first sentence, saw he started mentioning the the Petrel and then just skipped the rest of the post".

I only re-read the post after his comment about "that's what I said"