Jay
Need to dive more!
From what I see with my limited data, is that meandering/slow ascents (even on square-like profiles) have a large effect on reducing SurfGF (of the leading tissue) and whilst NDL has an effect, it seems it's not as large as I thought it would be.
I've enjoyed watching and learning the behaviour of GF99 and SurfGF. SW recently added the ability to graph GF in Cloud. It's very interesting seeing how this plays out in the last 10m, along with its much larger than (I) expected difference vs. GFHi. (GFHi merely representing my user-input of how 'close to the limit' I'm willing to go (based on previous computer use (Geo2) ...). SurfGF tells me how close to that 'limit' in reality I go.
Rec Divers*: for the purposes of the poll, please eyeball you average SurfGF for NDL dives deeper** than 20m.
Please select the closest result. If your result(s) are >5% out of the poll %'s range, please comment and I'll manually add them into a SS and post the results. I'll also pair the above data and calc the differences. It will be interesting to see if GFHi has much effect on SurfGF [EDIT: <-- this comment is incorrect in the sense that SurfGF is profile dependent (see @ChuckP's Post2) and GFHi is merely an input below. GFHi does affect NDL, hence profile ...). Please do comment if you see a NDL <-> SurfGF effect / trend in your data.
Below are some explanations and more detail if some things addressed above are new to you. I've also listed my 'sample' of dives I used.
I use a GFHi of 90 and know of others the use use higher than that. Sometimes I hear 'oh, that's high' ... but it seems that number, whilst at the upper end, and perhaps because of a ?typical? Rec profile, isn't that high.
What, to me, seems to matter more is the SurfGF (my average is 50). Obviously this latter stat is merely the leading tissue, so I'm hesitant to place too much weight on what I *think* are low SurfGF values (relative to my 'high' GFHi) i.e. a high difference I'm 40% (90-50). I'd love to hear from those who possess more deco knowledge to weigh in on this.
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*Why just Rec divers: because Tec divers treat GFHi as a target. Light deco or Tec/Rec are excluded as I don't know if/how much it will bias the results. I'd be interested to hear from light deco say <10-15mins of deco).
**why deeper than 20m: dives shallower than this seem to have SurfGFs close to or below 30. I'm wanting to concentrate the data input range to see if it results in a concentration of SurfGFs.
GF99 at the surface = SurfGF, and when NDL=0, SurfGF=GFHi. If on a dive using a GFHi of 85%, and your NDL=zero, then GFHi=SurfGF=85% and if you went straight to the surface at 9m/min then you'd surface with 85% (of the original (aka unmodified)) M_Value.
I've enjoyed watching and learning the behaviour of GF99 and SurfGF. SW recently added the ability to graph GF in Cloud. It's very interesting seeing how this plays out in the last 10m, along with its much larger than (I) expected difference vs. GFHi. (GFHi merely representing my user-input of how 'close to the limit' I'm willing to go (based on previous computer use (Geo2) ...). SurfGF tells me how close to that 'limit' in reality I go.
Rec Divers*: for the purposes of the poll, please eyeball you average SurfGF for NDL dives deeper** than 20m.
Please select the closest result. If your result(s) are >5% out of the poll %'s range, please comment and I'll manually add them into a SS and post the results. I'll also pair the above data and calc the differences. It will be interesting to see if GFHi has much effect on SurfGF [EDIT: <-- this comment is incorrect in the sense that SurfGF is profile dependent (see @ChuckP's Post2) and GFHi is merely an input below. GFHi does affect NDL, hence profile ...). Please do comment if you see a NDL <-> SurfGF effect / trend in your data.
Below are some explanations and more detail if some things addressed above are new to you. I've also listed my 'sample' of dives I used.
I use a GFHi of 90 and know of others the use use higher than that. Sometimes I hear 'oh, that's high' ... but it seems that number, whilst at the upper end, and perhaps because of a ?typical? Rec profile, isn't that high.
What, to me, seems to matter more is the SurfGF (my average is 50). Obviously this latter stat is merely the leading tissue, so I'm hesitant to place too much weight on what I *think* are low SurfGF values (relative to my 'high' GFHi) i.e. a high difference I'm 40% (90-50). I'd love to hear from those who possess more deco knowledge to weigh in on this.
----------------------------------------------------------------------------------------------------
*Why just Rec divers: because Tec divers treat GFHi as a target. Light deco or Tec/Rec are excluded as I don't know if/how much it will bias the results. I'd be interested to hear from light deco say <10-15mins of deco).
**why deeper than 20m: dives shallower than this seem to have SurfGFs close to or below 30. I'm wanting to concentrate the data input range to see if it results in a concentration of SurfGFs.
GF99 at the surface = SurfGF, and when NDL=0, SurfGF=GFHi. If on a dive using a GFHi of 85%, and your NDL=zero, then GFHi=SurfGF=85% and if you went straight to the surface at 9m/min then you'd surface with 85% (of the original (aka unmodified)) M_Value.
