Let's compare our conservatism setting

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zixzax

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Hi all. May I propose we compare our computers conservatism setting and dive plan results, so that everyone has an idea about NDL on different brands and conservatism settings. If you think it's an interesting idea, join me with following format:
Garmin Descent MK1
30m (or 100ft)
AIR
Low(45/95) NDL 14'31"
Medium(40/85) NDL 11'42"
High(35/75) NDL 9'12"
(Nitrogen in tissue: 0%)
 
Good idea. It will give you an idea for the first dive but some computers will start to yield more significant differences after repetitive diving vs just the first dive, especially when diving a see-saw profile or with quicker ascents. ( The latter I am thinking of Suunto specifically re: profile and ascents.)
 
Good idea. It will give you an idea for the first dive but some computers will start to yield more significant differences after repetitive diving vs just the first dive, especially when diving a see-saw profile or with quicker ascents. ( The latter I am thinking of Suunto specifically re: profile and ascents.)
You are right. Maybe we add a value like Remaining N2?
 
If you're really interested in this stuff, I recommend you first download the 1994 DSAT report (free from Rubicon Foundation) and read at least the intro. Then there's Powell's Deco for Divers that may be available on interlibrary loan, ask your librarian. Erik Baker's papers are freely available on-line in PDF format, though they assume you're already familiar with the background information.
 
Good idea. It will give you an idea for the first dive but some computers will start to yield more significant differences after repetitive diving vs just the first dive, especially when diving a see-saw profile or with quicker ascents. ( The latter I am thinking of Suunto specifically re: profile and ascents.)

I'm with @outofofficebrb 1st dive NDLs tell only a small part of a computer's decompression algorithm behavior.

This is what I see.

Compiled from my recollection and data in Macdive.
Dive 1
Gas: EAN31
Max depth: 115fsw
Avg Depth: 75fsw
Length: 37minutes
Shearwater Teric at 45/85: 1 minute no stop time left at ascent
Suunto Cobra 3: about 10 minutes no stop time left at ascent (can't say for sure as Suunto doesn't report that to Macdive)

1 hour surface interval

Dive 2:
Gas: EAN31
Max Depth: 114fsw
Avg Depth: 60fsw
Length: 45minutes
Shearwater Teric: 1 minute stop at 10fsw that cleared on ascent
Suunto Cobra 3: 15 minutes of deco at 10fsw
 
Hi all. May I propose we compare our computers conservatism setting and dive plan results, so that everyone has an idea about NDL on different brands and conservatism settings. If you think it's an interesting idea, join me with following format:
Garmin Descent MK1
30m (or 100ft)
AIR
Low(45/95) NDL 14'31"
Medium(40/85) NDL 11'42"
High(35/75) NDL 9'12"
(Nitrogen in tissue: 0%)

I too like your general concept and I'm also quite interested in those things, and it's an important one (IMO at least) to for divers to know (how their computer works, and relative to other computers), but to get 'meaningful info' (<--that's heavily relative!), it needs to be on a repetitive dive basis and then there's the problem of matching profiles, computer settings (GFs, other 'conservatism etc, SIs, and how they're handled), and then there's the problem of what to measure and when. Say you select NDL, when do you measure it?

What it comes mainly down to is the algo the computer uses. If you have a search of my name you'll see I've started and been involved in many computer/algo related threads. Several of us on here have crunched the ScubaLab data in different ways and have come up with similar conclusions which more or less (broadly speaking) is about your topic. Keep in mind that the ScubaLab results are just snapshots for certain dive profiles; it's not a scientific study and apart from ScubaDada's extensive experience with DSAT and 16-C that you'll see in the other posts there's not a lot of data out there. Also @CandiveOz has done some nice threads listing default & pre-set GFs.

One thing I think that is current and interesting is how RGBM2 handles various SIs relative to Fused and 16-C.

Anyways, don't be dissuaded in your endeavour ... :)
 
I too like your general concept and I'm also quite interested in those things, and it's an important one (IMO at least) to for divers to know (how their computer works, and relative to other computers), but to get 'meaningful info' (<--that's heavily relative!), it needs to be on a repetitive dive basis and then there's the problem of matching profiles, computer settings (GFs, other 'conservatism etc, SIs, and how they're handled), and then there's the problem of what to measure and when. Say you select NDL, when do you measure it?

What it comes mainly down to is the algo the computer uses. If you have a search of my name you'll see I've started and been involved in many computer/algo related threads. Several of us on here have crunched the ScubaLab data in different ways and have come up with similar conclusions which more or less (broadly speaking) is about your topic. Keep in mind that the ScubaLab results are just snapshots for certain dive profiles; it's not a scientific study and apart from ScubaDada's extensive experience with DSAT and 16-C that you'll see in the other posts there's not a lot of data out there. Also @CandiveOz has done some nice threads listing default & pre-set GFs.

One thing I think that is current and interesting is how RGBM2 handles various SIs relative to Fused and 16-C.

Anyways, don't be dissuaded in your endeavour ... :)
Great reply and I appreciate. I will look into it.
 
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Hi guys. I am a newbie and to be honest I don't quite understand your reply which is out of my knowledge. But I am happy to learn.
I guess I might not have explained my intention well enough. I have got my first computer recently and I am curious about whether there is huge gap in terms of NFL between different brands even if they are set with similar conservatism (GF value).
I can do a dive plan (by an app) on my computer and get the result. I just input the depth and GF and oxygen proportion and get the result. I assume that your computers can do the similar thing.
To make it simple, we calculate our first dive only. And maybe Buhlmann GF algorithm computers only..
Cheers
 
https://www.shearwater.com/products/teric/

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