[PATCH] Support different salinity in planner

[Anton Lundin]

On 13 November, 2014 - Linus Torvalds wrote:

> On Nov 13, 2014 2:04 PM, "Anton Lundin" <glance at acc.umu.se> wrote:
> >
> > This came out of a discussion with a frend who had his Uwatec 330 show
> > him a depth of 72 meters while his Liquivision Xen showed him 69 meters.
> > This was due to that his Xen was set in salinity mode, while Uwatec 330
> > always shows a depth calibrated against fresh water.
> 
> Wow. What an odd choice. But I checked the manual, and it's documented. I
> guess the idea is that that way it at least shows a deeper depth than real,
> so it's that conservative choice.
> 

Yes, i found it in the manual too. I first suspected something down that
line, but in the reverse, since you can't adjust the Uwatec but you can
adjust the salinity in the Xen.

> Anyway, I didn't mean to say the patch shouldn't be applied, it's more if a
> "you seldom even know what the dive computer does, or the actual real
> depth". It might be a good idea to warn about it, especially since planning
> using fresh water gives you deeper dives, so while calibrating a dive
> computer for fresh water is arguably conservative, *planning* for fresh
> water is not. If your dive equipment shows saltwater depth, you're now
> diving at higher pressures than you planned for if you follow the depth
> profile..
> 

I'm all for sane and conservative defaults. Thats why i made sure it
defaults to 1.03 kg/l, the same value as we used in the planner before,
and i choose to _not_ save the value between plans, so if you do want to
plan "fresh-water-dives", you need to do a conscious choice.


//Anton


-- 
Anton Lundin	+46702-161604