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So if I planned a DECO dive I would also ask my dive partners what GF setting they have for the dive. I prefer everyone is on the same GF for that but hey that's just me. Good thing with the Shearwater is that if you do exceed NDL you would often clear the need for a deep stop by simply ascending to a shallower depth for some time.

The entire concept of having an adjustable or even known GF is pretty modern. Even just 10-12 years ago it was rare to have any kind of way to track how close you were to your hi or low. Most people moved time around and/or especially added time deeper - since "deep stops" were in vogue. Even after using buhlmann based PC software it was common to add 1min stops below the 30/85 or whatever was run. Even today on basic 1 deco gas, 25mins of deco kinds of dives its pretty common to have stops below your GF low because its rare to have a first stop anywhere close to 70ft for the EAN50 switch.

Or the ascent looks like this and doesnt actually match whatever GF you have in your computer. So its been a longstanding issue, that whatever GF low you think you are using, its almost assured that your actual GFlow is much much deeper - it has been that way for years and years
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The answer is always Shearwater :)
You said you're getting on so if your eyes are getting tired, get the Perdix.

I also got tri focal intraocular lenses installed at the Eye Vision Institute in Sydney. Also had cataracts done at same time. They remove you existing lens and replace it with a new improved tailor made lens.

perfect vision now in both eyes. Trifocal allows for good far, intermediate distance vision and close-up focus. 15k poorer but the lifestyle change is great no glasses ever again.

So works great with my Perdix and my Cressi digital console.
 
The answer is always Shearwater :)
You said you're getting on so if your eyes are getting tired, get the Perdix.
Thanks, eyesight is not the best so I use prescription lenses in my mask
 
I also got tri focal intraocular lenses installed at the Eye Vision Institute in Sydney. Also had cataracts done at same time. They remove you existing lens and replace it with a new improved tailor made lens.

perfect vision now in both eyes. Trifocal allows for good far, intermediate distance vision and close-up focus. 15k poorer but the lifestyle change is great no glasses ever again.

So works great with my Perdix and my Cressi digital console.

I had Bausch & Lomb Crystalens HDs implanted 8 or 10 years ago, followd by LASIK operations on my Corneas in order to correct the remaining astigmatism.
Wow, what a difference, the Crystalens are focusable IOLs so my vision is perfect at every distance from 8" to infinity. Best 7 to 8 grand I ever spent.
Michael
 
The other thing is that I may end up diving with others using different dive computers which will give them less time to NDL and I have to remind them to dive to their own dive computer and pay attention. I had one dive buddy who didn't and her Suunto had her do a 25 minute stop at 5m. We were on a second morning dive and she lost track of her dive computer I have no idea if that she must have exceeded NDL ( I had not )

25 min at 5 m would require loading a relatively slow tissue compartment without also loading the faster ones (and requiring deeper stops to clear them). On a no-stop dive that should've generated "light deco" maybe. I suppose it's mathematically possible to keep ascending at a rate that will clear the faster compartments without a stop, until you hit that particular TC... but on a real dive I'd call shenanigans on it.

 
I had one dive buddy who didn't and her Suunto had her do a 25 minute stop at 5m. We were on a second morning dive and she lost track of her dive computer I have no idea if that she must have exceeded NDL ( I had not )

25 min at 5 m would require loading a relatively slow tissue compartment without also loading the faster ones (and requiring deeper stops to clear them).
I, too, find this suspicious. A 25 minute stop at 5mm is a serious decompression obligation, and it should have been preceded by an earlier stop. On the other hand, something like that could happen with a Suunto, although not on a dive such as you describe.

A very long time ago, before I had taken any tech classes, I did a dive that produced similar deco on my Suunto Cobra. It was on my 5th day of diving on a Liveaboard, with the previous days featuring about 4 dives per day. We all skipped the normal first dive in preparation for the second dive, which was on the San Francisco Maru in Chuuk Lagoon. I went to a maximum depth of 181 feet/55 meters in the hold, and did the rest of the dive on the deck, for a total of 15 minutes of bottom time. I remember that I did more than 20 minutes of deco, and my buddy, running DSAT on his computer after having done all the rest of the dives with me that week, went up to take a nap long before me. I later realized that my personal setting had somehow been set on the medium setting, which is why my buddy had been calling me Captain Deco all week.

I'm guessing your buddy with the 25 minutes at 5 meters did not have that sort of dive.
 
25 min at 5 m would require loading a relatively slow tissue compartment without also loading the faster ones (and requiring deeper stops to clear them). On a no-stop dive that should've generated "light deco" maybe. I suppose it's mathematically possible to keep ascending at a rate that will clear the faster compartments without a stop, until you hit that particular TC... but on a real dive I'd call shenanigans on it.

25 minutes at 3 to 6 is a perfectly normal Suunto stop. Get DM5 out, set it to Zoop and go far enough over NDL to get a decent length stop, it will be at 3.
 
25 minutes at 3 to 6 is a perfectly normal Suunto stop. Get DM5 out, set it to Zoop and go far enough over NDL to get a decent length stop, it will be at 3.

With no deeper stops? Considering RGBM's penchant for deep stops? Interesting...
 
https://www.shearwater.com/products/peregrine/
http://cavediveflorida.com/Rum_House.htm

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