Video 9 - The Amazing Power of GF 99 (FINAL Video based on Andy Davis’s article)

GF99 (Woody calls it “the speedometer of Gradient Factors”), if used properly with PROPER TRAINING, can be very powerful!
Quoted from Andy Davis below in his article “Shearwater Dive Computer Settings: Become A Power User!”
Know if you are absorbing or releasing nitrogen.
Understand your off gassing efficiency.
Help avoid causing decompression stress.
Have flexible real time control over conservatism.
Optimize the length and depth of safety stops.
Monitor how quickly your nitrogen level drops.
Conduct ideal multi level dives.
It’s totally OK to leave your Shearwater computer on the default settings. In fact I recommend you do until properly trained and fully show an instructor that you have a very good understanding of the settings discussed in this series. But Shearwater computers are powerful and if utilized correctly, you can take advantage of your Shearwater’s dive instruments (such as GF99 and SurGF) and really enhance the efficiency of your off gassing.
Andy’s full article can be downloaded at (highly recommended):
www.buymeacoffee.com/andydavi...

[@piotrweclewski5857]

I think your next favourite article in series of 'shearwater power user' could be Mark Powell's 'Evolution of dive planning' from shearwater blog

[@391wombat]

Thanks Woody, very well done. I generally understood the concepts before your videos, but they really drove it home. Tell Andy he owes you some royalties, or at least some post dive day cocktails!

[@picahudsoniaunflocked5426]

Found the second channel yay! Woody looks different without a crochet cephalopod on his dome. Great to see his in-depth [no pun intended] teaching.

[@PedroOjeda]

I LOVE Gf99 and GfSur. Main reason I will never switch away from shearwater

[@robertrichard8716]

Thanks!! That will change my diving, it will help to dive more safely.

[@diversdown2116]

thank you i have learned a lot now i cant wait to watch my computer. keep the shearwater stuff coming

[@JamesTurner-xf6fn]

Thanks Woody!!! The whole series has been awesome. Has motivated me to research myself. BIG THANK YOU 👏👏👏👏👏

[@DIVETALKPLUS]

Important to understand it fully before making any setting changes but so glad Andy published this great article. We all learned a lot from it including me. Better to be conservative that’s for sure.

[@davedonati206]

Hi Woody, thanks for educating us on this subject. Well done!

[@RAVINGMUNSTER]

Really enjoyed this series - I had already read the article some months ago, but this refreshed and clarified it for me. Would love to see a video on the learning from your DCI incident- I know that you're friends with the likes of Doug Ebersole (who could perhapsbe involved), so I'm guessing you've received some awesome advice- which would make for a great educational video for viewers. You seem really confident getting back in the water, I'm think many of us would love to hear about the advice that has maintained that positive Woody confidence!

[@DIVETALKPLUS]

Thanks for the post. Yes thankfully all dive’s since have gone without incident. I discuss it some in an upcoming dive talk video so stay tuned and we will eventually do a follow up once we meet with DAN. I must say im pressed with changes I’ve been told they are making. Thanks again for the post.

[@picahudsoniaunflocked5426]

I hope they do multiple follow ups on both channels. There are so many ways to discuss & learn from Woody's experience, from the psychology of returning to the waters to perspectives on how surface teams can be better prepared for incidents, to the DAN aspects, & a dozen more . I wonder if Woody + Gus would consider doing an AMA specifically about the incident once they catch us up on DAN responses.

[@ianstockdale964]

Hi woody I’m from the Uk. I’ve tried to purchase this but it doesn’t seem to let me. Is this for USA only

[@ronenshaul1217]

A question: I’m a technical diver, enjoying and understanding my Shearwater well. However many times I go for no-stop dives with friends that own other computers, simpler ones, recreational dives only, with far less information. And always, at the end of the dives, my NDL is shorter than theirs by few minutes. My question (theoretically only, I’m not going to do it, just for my understanding): What should I have done in order to get the same NDL as theirs? Set my GFhigh to 100? Thanks, Ronen

[@DIVETALKPLUS]

Thanks for the question. I would not recommend setting GF High to 100. Many factors can contribute to different NDLs. No way to answer from this text and without understanding the entire dive profile. I’d suggest using the default settings at medium to high conservative level and then perhaps get with your local dive shop or instructor to review your dive log and compare to theirs and see if you can determine the difference. There are so many variables that can affect that. But please don’t change that setting to 100. That would not be prudent. I’d much rather have a shorter NDL then change settings without fully understanding their impact. Stay safe, that’s the most important lesson of this video series.

[@ronenshaul1217]

@@DIVETALKPLUS thanks!

[@albertokusmic9239]

Great collection of videos full of concepts, valuable content, expertise and passion. Many thanks for sharing all this, Woody! Is GF99 and SurfGF a peculiar feature of Shearwater products (I own a Petrel2, btw..), or it is shared also by other dive computer brands? Thanks and ciao from Italy 👋👌

[@DIVETALKPLUS]

I only use Shearwater so I’m just not qualified to comment on any other computer. For me I simply will only use Shearwater computers for many reasons. They are an amazing company with amazing dive computers.

[@391wombat]

Woody do you have to have a tech diving Shearwater computer for this article to be relevant? In other words if you’ve got a Peregrine or the new Tern TX, does this article apply?

[@DIVETALKPLUS]

I don’t dive with those two models but their user manual would show you what functions are available. However for recreational diving, I’d recommend using the default settings until you can take a class with an instructor related to deco diving. Stay safe!

[@391wombat]

@@DIVETALKPLUS Trying to absorb it all. It kinda sounds like every dive really has its own ideal safety stop depth and duration. Yes?

[@dpthdiver]

All Shearwater computers have the GF99, SurfGF, @5 and ^5 displays.

[@andrewhughes7190]

Awesome stuff again Woody 👏 Question 🙋‍♂️ was your GF high at 70% when you got bent ? Or is it your new GF ? Once again thanks 🙏 for your brilliant content

[@DIVETALKPLUS]

I was using a 40/70 GF

[@andrewhughes7190]

@@DIVETALKPLUS interesting 🧐 I’m pushing 53 years and thought I was conservative with a GF high of 80 ! Diving CCR I get out of the water feeling better than when I get in lol