On a NDL dive, which computers' NDLs are not affected by GFLo?

[KenGordon]

Well yeah, to repeat what I said elsewhere, that was an example designed to illustrate an extreme case, not a recommendation for how to plan that dive. I think it's still a valid observation even for less extreme cases. See also: 10,000 forum posts about how deep stops have probably been overemphasised in the past.

(Also, that is kind of a weird response - do you suggest picking your deco gases to work around quirks in your algorithm? Particularly when it is kind of obvious that there isn't any real physiological basis behind it, it's just a mathematical quirk?)

Well, Bühlmann didn't talk about gradient factors at all, that was that Erik Baker bloke.

Since GFs are already a graft on top of Prof. Bühlmann's work, why not discuss other approaches of grafting...

Because by varying the GF per compartment you are directly changing the relationship between compartments. The choice of the relationshipsis part of Bulhman work. I am not sure how you’d reason the choices, but then your new algorithm would have no more in common with ZHL16 than with DSAT, a Suunto or 1950s tables.

 

[jale]

Checked with a Divesoft.
GFlo doesnt affect NDL

 

[jale]

with AV1 it does affect it!

 

[Jay]

Checked with a Divesoft.
GFlo doesnt affect NDL

with AV1 it does affect it!

Thanks @jale for the info. Looks like we've found our first computer.

Was the NDL difference large?

 

[scubadada]

with AV1 it does affect it!

Hi @jale

I've never seen an AV Underwater Technologies AV1. They appear to have 1 US dealer on Maui, Hawaii. Where are you located? Where do AV1 computers come from, Russia? Only other link I could find as Divex3me, ? from Italy

 

[stuartv]

Thanks @jale for the info. Looks like we've found our first computer.

Was the NDL difference large?

Well.... I finally did a search and found where I checked this info a couple of years ago.

Shearwater Perdix AI oddities: GF settings and dive planning

The Seabear H3 did have it where the GF Lo affects the NDL.

You may also notice my post immediately following the one I linked, with an email from Shearwater that says "Note that this is consistent with saying that only GF_High controls the NDL time".

 

[jale]

Thanks @jale for the info. Looks like we've found our first computer.

Was the NDL difference large?

Will recheck the details later when i am home but 3 min for a 30M 20min on 32%

 

[jale]

Hi @jale
I've never seen an AV Underwater Technologies AV1. They appear to have 1 US dealer on Maui, Hawaii. Where are you located? Where do AV1 computers come from, Russia? Only other link I could find as Divex3me, ? from Italy

I ordered directly in Russia. I live in Asia.
Good and fast service.
I use it with my Sidekick and no problems after about 200 hours with longest dive at almost 4 hours and deepest to 122M. Most dives in sea water.

 

[dmaziuk]

Because by varying the GF per compartment you are directly changing the relationship between compartments. The choice of the relationshipsis part of Bulhman work. I am not sure how you’d reason the choices, but then your new algorithm would have no more in common with ZHL16 than with DSAT, a Suunto or 1950s tables.

You'll still have 16 compartments and their half-times. (And the choice of 4 or 5 minutes for the first one.) Where do you draw the line, though: by adding varying degree of conservatism w/ the sliding slope of factors, don't you change the overall off-gassing dynamics enough to not be "Buhlmann" already?

 

[Jay]

Here's an updated list ... not many to go now.

GFLo basically* does not affect NDL on a NDL dive (source)
Shearwater
Dive Rite's discontinued Nitek - Q (post#2)
Deep 6 (post#93 and via PM)
Garmin Descent (from a Descent diver via PM)
TDC-3 (email and post#69)
Seabear H3 (the link in post#126)
Heinrichs Weikamp (post #4 of StuartV's link in post#126)
Dive Soft (post#122)
AV1 (post#123) <--?provisional (post#135)

GF Lo affects NDL on a NDL Dive
none yet

Unknown (yet) but do have custom GFs (i.e. easy to know if GFLo affects NDL)
Mares - Genius (awaiting email response - if someone's near a shop with one feel free ....
Ratio/SEAC (Tech+ has custom GFs)
Scubapro - HUD (anyone got access to play with one?)
Suunto EON Steel <-- need to wait for 16C implementation (?post launch of the D5)

Unknown but doesn't have custom GFs (probably impossible to discover)
Liquivision Lynx

Well.... I finally did a search and found where I checked this info a couple of years ago.

Shearwater Perdix AI oddities: GF settings and dive planning

The Seabear H3 did have it where the GF Lo affects the NDL.

You may also notice my post immediately following the one I linked, with an email from Shearwater that says "Note that this is consistent with saying that only GF_High controls the NDL time".

Thanks for that @stuartv. A very interesting and relevant thread.

*basically means for all intents and purposes e.g: stops clear as you arrive at them, or, there is only a small unique window (e.g. a few meters to the surface) etc etc .... and rather than making a blanket statement which could be argued is technically incorrect ... leading to ambiguity of what the results practically mean for other divers that haven't read the whole thread in detail.