Allow Water Temperature to Stabilize Before Recording High

Suggestions? Comments? Features you'd like to see?
Post Reply
Bollar
Posts: 50
Joined: Mon Nov 20, 2017 10:29 am
Dive Computer: Shearwater Perdix AI

Allow Water Temperature to Stabilize Before Recording High

Post by Bollar »

I guess this is a minor request, but since I turn my computers on before entering the water, MacDive records a very high water temperature for the first few minutes of the dive. I'd like the option to have that stabilize before "High Temperature" is recorded -- perhaps simply by not filling in that field until a few minutes of the dive have elapsed.

And really, for the simple dives that I do, the temperature at the safety stop or end of the dive would work great for my purpose.
User avatar
nick
Site Admin
Posts: 4361
Joined: Sat Apr 12, 2008 8:33 am
Dive Computer: Shearwater Teric
Contact:

Re: Allow Water Temperature to Stabilize Before Recording Hi

Post by nick »

I don't think this is about turning the device on beforehand. I think it's more to do with how hot the device itself is / how its temperature sensor works? At least, that's my understanding. That said, I appreciate the problem you are reporting as I have a similar computer and a dive with 38c as the high temp. Trying to re-interpret the data always gets me in trouble though.

Picking the safety stop temperature is fairly arbitrary. I wouldn't implement that for the general case. But if that's what you want then you can easily (albeit manually) edit that yourself after the fact.

Waiting a few minutes to stabilise is more palatable, but even then, it's making assumptions. I forget what Shearwater Desktop/Cloud does in this case, I'll have a look tonight.
Bollar
Posts: 50
Joined: Mon Nov 20, 2017 10:29 am
Dive Computer: Shearwater Perdix AI

Re: Allow Water Temperature to Stabilize Before Recording Hi

Post by Bollar »

Thx for looking -- yeah, I edit by hand now and choose the reading from when I exit. I figure I'm within a degree.

I find that the temp stabilizes between 8-12 minutes into the dive, but at that point, I could be at any depth, so I wouldn't really want to use that either.

Shearwater doesn't edit the value and shows the initial 38c reading as the high.
Bollar
Posts: 50
Joined: Mon Nov 20, 2017 10:29 am
Dive Computer: Shearwater Perdix AI

Re: Allow Water Temperature to Stabilize Before Recording Hi

Post by Bollar »

I reread the Perdix AI manual last night and noticed their comment on temperature accuracy:
Note that the case insulates the temperature sensor, so allow 10 to 15 minutes for the temperature to reach the actual environmental temperature.
So, if you chose to look at this, I'd suggest an option to discard the first fifteen minutes of temperature readings from the individual dive's high/low temperature calculation.
Taniwha
Posts: 12
Joined: Fri Apr 29, 2016 4:04 pm
Dive Computer: Shearwater Perdix AI

Re: Allow Water Temperature to Stabilize Before Recording Hi

Post by Taniwha »

I made a feature request to Shearwater a few years ago asking if they could implement air temperature recording. They said they would look into it as they could see it would be useful. Maybe this has been done now?

If so, then this could perhaps allow some sort of workaround?
Post Reply