I've made a decision. I won't be posting anymore. All I did was ask for a software change for OC Rec mode. It has been pointed out how stupid my request is. Even if the last stop of 15ft doesn't mean anything for "Safety Stop" in OC Rec mode, if I change to OC Tec for different displays, 15ft last stop would make me happy. Besides, the manual says 10 or 20 feet and in OC Rec mode, I have only been able to see 10ft last stop while in System Setup.
Cheers - M²
it wasn't made to make you feel stupid. It's trying to help understand what that setting does and what it means for you diving, and why you feel like it may be beneficial to you. So please hear me out.
I think the part that you're confusing though is that the computer does not treat "safety stop" like it does "deco stop", and I think the manual may be a bit confusing because it says "last stop" and doesn't really define it further. Shearwaters focus since they started has been on rebreather and technical OC divers up until a couple years ago when the Rec mode was released, so it may be a learning opportunity for them in writing this manual to help clear up confusion since it has come up twice this week.
The last "deco stop" is 10ft, and all of the divers that I know, use 10ft as their last stop setting. They do this because it keeps the computer happy if you have to/want to go up to a 15ft hang bar, or there is a cool part of the cave at 10ft *or easy part of the cave*, or a habitat, or whatever where you may not want to stay down at 20ft, and don't want your computer to be flashing red and asking you to confirm that you violated a stop depth which is annoying.
The caveat here is that if you don't plan on going above 20ft for your final stop, then your TTS number will be a few minutes off if you are decompressing on something other than 100% O2.
Note that this setting does not change the "safety stop" parameters and I think this is where the confusion has come up.
The "safety stop" is a target window for you to hang out after your deco has cleared, or if you are NDL diving, just an added safety buffer to minimize your risk of DCS. The "last stop" setting doesn't actually change the window of the "safety stop" which is why the safety stop countdown doesn't display a target depth. Once you are above 20ft and you have cleared all deco stops, the timer starts, and as long as you stay between 7ft and 23ft, the timer keeps on ticking. This is a nice wide buffer to give you flexibility to move around because all you are doing is helping those tissues to offgas a bit more before you come down. You may choose to do a minute at 20, a minute at 15, a minute at 10 and go up, may choose to do it all at one depth, may bounce around looking at pretty fish or playing pranks on your buddy, but because it isn't a "Deco stop" and your "ceiling" is the surface, you can go around wherever you want and be OK.
Does that make sense or help at all?
@tcoen may be able to validate, but I think they probably left the "safety stop" window relatively wide from 7ft down to 23ft partly because it removes screen clutter, but also to remove the "pressure" put on a diver from feeling like they have to abide by the stop depth and if they go shallower that they may get bent. Which would probably keep their customer service lines open 24/7. Having participated in both of these threads this week though, I think on the "support" page it may be worth changing the normal manual to "OC Tec and CCR" manual, and then having a standalone manual for the Rec Nitrox mode since that appears to be what caused the confusion in both of these threads
