Clarification on air consumption profile calculations

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sdridentity
Posts: 10
Joined: Sun Nov 05, 2017 12:24

Clarification on air consumption profile calculations

Post by sdridentity »

Hi,

Well done, congrats on 20th anniversary :-)

I experience some behaviors I do not understand with the air consumption profiles -- Using 6.0.11 (Update 1).

If I take three dives from my logbook:
Dive 1: Start and End Pressure set, Avg Depth set, DC Profile, NO DC air measures (Vyper) Profile 2 data shows values
Dive 2: Start and End Pressure set, Avg Depth set, DC Profile, NO DC air measures (Vyper) Profile 2 data shows NO value
Dive 3: Start and End Pressure set, Avg Depth set, DC Profile, DC air measures (Vyper Air) Profile 2 data shows values

If I set Profile -> Profile 2 to Tank Pressure 1, profile 2 Graph shows:
Dive 1: a linear trend from start to end pressure
Dive 2: no profile (empty)
Dive 3: the recorded profile values

If I set Profile -> Profile 2 to Tank Pressure (calculated), profile 2 Graph shows the correct calculated SAC for all three dives.

My questions:
Q1: Why is the Profile 2 data of dive 2 empty? Normally, it gets populated when Start, End and Avg Depth are set? I assume this is also why the graph is empty... I have 4 dives like that. In Tank & Gas detail, everything looks ok, even with a SAC calculated value
Q2: Is there a way to set things up so the recorded (DC) air profile data is used, and if absent, revert to SAC?

Thanks!
Simon.
divinglog
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Re: Clarification on air consumption profile calculations

Post by divinglog »

Hi Simon

Thank you very much!

Tank Pressure 1, 2 & 3 is always recorded data from the tank pressure sensor, never calculated or populated from manual data. Only Tank Pressure (Calculated) is calculated based on start pressure, end pressure, depth and SAC rate. So Dive 1 must have tank pressure values from somewhere. Maybe you've drawn them in the profile editor some time in the past?

Kind regards,
Sven
sdridentity
Posts: 10
Joined: Sun Nov 05, 2017 12:24

Re: Clarification on air consumption profile calculations

Post by sdridentity »

Thanks.

Most of the data (like Dive 1) was imported from Suunto DM 3.1. This is probably where the interpolated tank pressure data comes from (as I did not enter detailed tank pressure data myself).

Assuming that, is there a way to have, in one logbook, the pressure graph showing the "best available" tank pressure data, i.e. the sensor data when available or the calculated otherwise? Or alternatively, is there a way to "generate" the tank pressure data points from the start/end pressure depth and SAC?

Thanks,
Simon.
divinglog
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Re: Clarification on air consumption profile calculations

Post by divinglog »

Hi Simon

Yes, maybe Suunto DM has interpolated the data. I don't think an "automatically pick the right profile" cannot be implemented in a non confusing way. Normally users have either an air integrated dive computer or not. Users without AI computer will always pick the calculated profile and users with AI sensor will pick the measured profile. I can't imagine how to implement such an automatic function so user will know what it does.

Sven
sdridentity
Posts: 10
Joined: Sun Nov 05, 2017 12:24

Re: Clarification on air consumption profile calculations

Post by sdridentity »

Hi,

I understand this may not be a very typical scenario. Although I imagine many who have
dived for some time probably went through more than one computer model and setup.

I did find a workaround, at least to print the log correctly.

I created two report files: one with Pressure 1 Content and one with PressureCalc Content.
Then I can print ranges of dives using the relevant report.

To clarify the function I thought was simplest to use: in the profile editor, there could be a
function to "Write the calculated pressure to Tank x Pressure" field, as a one-time action.

Thanks, and hope this helps.

Simon.
divinglog
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Re: Clarification on air consumption profile calculations

Post by divinglog »

Hi Simon

Yes, in profile editor such a function could make sense. I think it might be indeed useful to automatically create a tank pressure profile.

Kind regards,
Sven
sdridentity
Posts: 10
Joined: Sun Nov 05, 2017 12:24

Re: Clarification on air consumption profile calculations

Post by sdridentity »

Hi,

I still have issues with my logbook having a mix of dives with and without tank pressure data.

1. Is there a way to export the calculated tank pressure data e.g. csv?
2. Is there a way to import profile 2 data? (at first glance, I can export profile 2 data, but the Import function seems
to import always to profile 1... is that so?)
3. In the profile editor, all the changes I do to the profile 2 Tank Pressure field seem to be ignored (after I click Apply Changes and go back to the logbook, it is as if nothing has changed).

Thanks!
Simon.
divinglog
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Re: Clarification on air consumption profile calculations

Post by divinglog »

Hi Simon

1. Sorry, not at the moment
2. Yes, right now it only imports Profile 1. You can copy and paste every profile data type, but I think this won't help you, because you probably want to edit the data.
3. This should work. Is the data still displayed in the profile editor after you've saved and refreshed?

Kind regards,
Sven
sdridentity
Posts: 10
Joined: Sun Nov 05, 2017 12:24

Re: Clarification on air consumption profile calculations

Post by sdridentity »

Hi,

>> 3. This should work. Is the data still displayed in the profile editor after you've saved and refreshed?

Here is what I experience:
- Logbook shows Tank Pressure values
- In Profile Editor, I clear all Tank Pressure Entries to 0
- The graph stops showing any blue line for Pressure (correctly rendering this as 'empty')
- Apply Changes
- If I Refresh, Tank Pressure stays at 0 in that view
- Going back to logbook, all the Tank Pressure entries are back to their original values!

BTW I am on the latest 6.0.14.

Thanks,
Simon.
divinglog
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Re: Clarification on air consumption profile calculations

Post by divinglog »

Hi Simon

Thanks, I can reproduce this issue. It happens when a profile block is completely empty, then it is not saved into the logbook database. Please download this zip file and copy the content into the Diving Log 6.0 program folder. Then it should work.
Kind regards,
Sven
sdridentity
Posts: 10
Joined: Sun Nov 05, 2017 12:24

Re: Clarification on air consumption profile calculations

Post by sdridentity »

Hi,

Thanks, that fixed it!

I still would have a use for the functionality to 'materialize' the SAC calculation into Profile 2, one way or another.

Best regards,
Simon.
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