Announcing the SubGravity H3 - Powered by SeaBear

[Lorenzoid]

. . .
Or is there a presumption that these Rec computers have a GF setting that they just don't tell you what it is or let you change it? So, every Rec computer could be different for that just depending on what GF the manufacturer chose to use?

I believe that is essentially true. I recall reading (you like that citation?) that the "pure" Buhlmann ZHL-16C (i.e., GFs set to 100/100, i.e., zero conservatism) is estimated to result in a measurable incidence of DCS--like on the order of several percent. No Rec computer manufacturer would be crazy enough to let a diver dive that. I have to believe that all manufacturers add a safety or conservatism buffer, whether that's by gradient factors or some other means of providing a buffer.

 

[stuartv]

I believe that is essentially true. I recall reading (you like that citation?) that the "pure" Buhlmann ZHL-16C (i.e., GFs set to 100/100, i.e., zero conservatism) is estimated to result in a measurable incidence of DCS--like on the order of several percent. No Rec computer manufacturer would be crazy enough to let a diver dive that. I have to believe that all manufacturers add a safety or conservatism buffer, whether that's by gradient factors or some other means of providing a buffer.

Oh, really?

So, I just ran some things through Multi-Deco with GF100/100, compared to the NOAA NDL Air tables and the NDL table in the Oceanic Atom 3.0 manual.

NOAA Air NDL table gives 1:00:00 at 60'
M-D says 57:00 gives no deco. 1:00:00 gives 1:40 deco @ 20'
Atom gives 57:00.

NOAA gives 25:00 @ 100'
M-D says 16:00 gives no deco. 18:00 gives 0:20 deco @ 20'. 21:00 gives 2:20 deco @ 20'. 25:00 gives 4:20 deco @ 20'
Atom gives 19:00.

NOAA gives 10:00 @ 130'
M-D says 10:00 gives no deco. 11:00 gives 0:20 deco @ 20'
Atom gives 11:00.

Are NOAA tables considered too liberal to actually use for Recreational diving? I don't have a PADI RDP or other "rec agency" version of an NDL table to consult.

Is an Oceanic computer using DSAT too liberal?

It seems like using a Tech computer set to GF100/100 and diving to NDLs is slightly more conservative than an Atom 3.0.

And considering the it seems like most everyone does a 3:00 safety stop at 15', which is 3:00 of deco that isn't even required, really how crazy do you think it is to do NDL dives with your computer set to GF100/100? It seems like it may be less crazy than diving an Oceanic Rec computer to its NDLs...

And yes, I realize this is not reflecting what they all might do for repetitive dives ... but the Oceanic computer and Multi-Deco are both using Buhlmann ZH-L16C, right? So wouldn't we expect those results to be similar also?

Also, I am not talking about using GF100/100 for deco dives. I am just talking about using a Tech computer to do Recreational NDL dives and setting it to give bottom times that match a common Recreational computer (presuming that many Aeris and Oceanic computers have the same DSAT algorithm and would produce basically the same results as an Atom).

 

[THRASH]

Also, still anxiously waiting for news on the H3 AI transmitter.

I fear with the way Randy has responded regarding this and the fact that it was mentioned on their website and now has been removed that AI might not be on the radar anymore. I am just presuming. I say this because if I was a merchant or manufacturer and had mentioned something was coming and then basically removed that information, and people repeatedly ask about it....I would at least say something like "It's coming guys don't worry about that. We are just facing some delays I don't wish to comment on." Something that would relay rest assured. That's my take at least.

 

[stuartv]

I fear with the way Randy has responded regarding this and the fact that it was mentioned on their website and now has been removed that AI might not be on the radar anymore. I am just presuming. I say this because if I was a merchant or manufacturer and had mentioned something was coming and then basically removed that information, and people repeatedly ask about it....I would at least say something like "It's coming guys don't worry about that. We are just facing some delays I don't wish to comment on." Something that would relay rest assured. That's my take at least.

Just for the record, the Sub-Gravity website does still list hoseless AI as optional for the H3. At least, in the comparison chart.

https://www.sub-gravity.com/comparison-chart/

But, since it appears that Sub-Gravity is a distributor and not the actual manufacturer, and I don't see AI mentioned anywhere on the SeaBear, I suppose the Sub-Gravity comparison chart must be taken with a small grain of salt.

 

[MixAddict]

Guys, please rest assured that the GFs are completely user adjustable and the user can make the NDLs as conservative or as liberal as he wants. In this regard, IMHO, the computer is suitable for both recreational as well as technical divers. It should literally last you throughout your diving career, at least until we come out with something much cooler!

With regard to AI - when we know something, you will know! I am not at liberty to say more than that at this time!

By the way, I will be in Cave Country for the next week with some demos if anyone wants to take one for a spin!

 

[THRASH]

Just for the record, the Sub-Gravity website does still list hoseless AI as optional for the H3. At least, in the comparison chart.

https://www.sub-gravity.com/comparison-chart/

But, since it appears that Sub-Gravity is a distributor and not the actual manufacturer, and I don't see AI mentioned anywhere on the SeaBear, I suppose the Sub-Gravity comparison chart must be taken with a small grain of salt.

I stand corrected. Thank you @stuartv for pointing that out.

Guys, please rest assured that the GFs are completely user adjustable and the user can make the NDLs as conservative or as liberal as he wants. In this regard, IMHO, the computer is suitable for both recreational as well as technical divers. It should literally last you throughout your diving career, at least until we come out with something much cooler!

With regard to AI - when we know something, you will know! I am not at liberty to say more than that at this time!

By the way, I will be in Cave Country for the next week with some demos if anyone wants to take one for a spin!

I will be in Jupiter, FL diving at the end of September and would love to take one for a spin. smiley face, but totally serious. How about you meet me there. You can even catch some lobster with me.

 

[Divetech99]

Hi, will the wireless integration work for iPhones?

 

[MixAddict]

If you are referring to the NFC, it currently works with Android devices only. Apple has not yet released its NFC protocols to developers except for Apple Pay and other secure transactions. We are seeing conflicting information on the timeframe when this will happen. I'm an iPhone user, so I am just as anxious as you are!

 

[scubadada]

Oh, really?

So, I just ran some things through Multi-Deco with GF100/100, compared to the NOAA NDL Air tables and the NDL table in the Oceanic Atom 3.0 manual.

NOAA Air NDL table gives 1:00:00 at 60'
M-D says 57:00 gives no deco. 1:00:00 gives 1:40 deco @ 20'
Atom gives 57:00.

NOAA gives 25:00 @ 100'
M-D says 16:00 gives no deco. 18:00 gives 0:20 deco @ 20'. 21:00 gives 2:20 deco @ 20'. 25:00 gives 4:20 deco @ 20'
Atom gives 19:00.

NOAA gives 10:00 @ 130'
M-D says 10:00 gives no deco. 11:00 gives 0:20 deco @ 20'
Atom gives 11:00.

Are NOAA tables considered too liberal to actually use for Recreational diving? I don't have a PADI RDP or other "rec agency" version of an NDL table to consult.

Is an Oceanic computer using DSAT too liberal?

It seems like using a Tech computer set to GF100/100 and diving to NDLs is slightly more conservative than an Atom 3.0.

And considering the it seems like most everyone does a 3:00 safety stop at 15', which is 3:00 of deco that isn't even required, really how crazy do you think it is to do NDL dives with your computer set to GF100/100? It seems like it may be less crazy than diving an Oceanic Rec computer to its NDLs...

And yes, I realize this is not reflecting what they all might do for repetitive dives ... but the Oceanic computer and Multi-Deco are both using Buhlmann ZH-L16C, right? So wouldn't we expect those results to be similar also?

Also, I am not talking about using GF100/100 for deco dives. I am just talking about using a Tech computer to do Recreational NDL dives and setting it to give bottom times that match a common Recreational computer (presuming that many Aeris and Oceanic computers have the same DSAT algorithm and would produce basically the same results as an Atom).

Hi Stuartv

Pelagic DSAT (Diving Science & Technology ) is based on the Spencer/Powel database with human Doppler studies and is the basis for the PADI RDP. Pelagic Z+ is based on Buhlmann ZHL-16C. I have asked Oceanic in the manufacturer's forum and by email what GF hi is for PZ+ and have not received a reply. I will have to call their tech support someday.

Air NDLs (min)
Depth (ft)	PZ+	DSAT	PADI RDP	NOAA
60	48	57	55	60
70	35	40	40	48
80	26	30	30	39
90	19	24	25	30
100	16	19	20	25
110	12	16	16	20
120	10	13	13	15
130	8	11	10	10

Nobody generally argues that any of these decompression algorithms is not safe. They do vary in the conservative to liberal spectrum. Neither Shearwater or Seabear includes NDL tables in their manuals. The Shearwater Petrel 2 recreational manual states that the low conservatism GFs of 45/95 yield similar NDLs to PADI and NOAA NDLs. Somebody with a Petrel and somebody with a H3 could fill in the missing columns in my spreadsheet. The H3 has default GFs of 35/85 but has 95/95 for comparison.

These are all 1st dive NDLs and do not represent repetitive dives. These, also, do not reflect deco dives. From personal experience, DSAT and PZ+ do not behave similarly for deco or repetitive deco dives. DSAT was developed for recreational diving whereas Buhlmann has broader application. This is another discussion.

Good diving, Craig

 

[Lorenzoid]

Stuart, I can't speak to the sample dives you ran through the different computers. Maybe the tests I had in mind were done for a broader sample of dives, including dives that would necessarily involve deco stops. Maybe they were even based on Buhlmann A or B rather than C. I do not believe the Petrel allows the user to set 100/100 in normal mode, though. As someone else pointed out, the Petrel Recreational Mode's "Low" conservatism setting corresponds to 45/95.