Posts Tagged ‘Technical Diving’

Deco calculations integrated in Diving Log

Monday, March 31st, 2014

This is something I wanted to implement for a long time and now I’m happy to announce that Diving Log has finally integrated deco calculations. I’ve implemented the Bühlmann ZH-L16 algorithm and now Diving Log can display data like NDL, ceiling, stop time and tissue saturation even if this data cannot be imported from the dive computer. Most sport dive computers do not record the relevant deco information and because of that, this data is missing in Diving Log and you have to go into the manufacturer software if you want to see it.

If you want to try it, please download the latest beta version first. In the logbook window, open the “Profile” tab and click the “Deco Calc” button to view the current dive in the new deco calculator window:

Open the deco calculator

Open the deco calculator

Deco Calculator

Deco Calculator with ppN2 tissue data

On the top, you have the depth profile with deco ceiling and gas switches. In the toolbar you have several display options and you can switch between the three ZH-L16 variants (A, B or C). You can also switch between data calculated by Diving Log and the data recorded and downloaded from your dive computer (if available). That way you can compare the results easily.

ppHe tissue saturation

ppHe tissue saturation

On the right side, you have a virtual dive computer display. Click anywhere into the profile on the left to update the computer display. On the “Gas” tab, you can quickly change the O2 and He values of the current gas for simulation. This will not change the gas stored in your logbook, so you can safely play around with the simulator to see how different gas mixtures influence the tissue saturation and deco profile.

ppO2 profile with gas configuration

ppO2 profile with gas configuration

On the “GF” tab, you can activate gradient factors (GF High and GF Low) to adjust the conservatism. When deactivated (GF 100/100), you have a pure Bühlmann calculation. When activated (default GF 30/75), you get a more conservative deco profile with a lower first stop and longer last stop. The gradient factor is not downloaded from the dive computer, so you may have to adjust it manually to your preference.

NDL / Stop Time with GF configuration

NDL / Stop Time with GF configuration

Additionally to tissue saturation, ceiling and stop time, Diving Log calculates the oxygen toxicity profiles CNS and OTU.

OTU and CNS profiles

OTU and CNS profiles

When you move the red cursor line around, Diving Log will not only update the dive computer display, it also updates the current tissue saturation [%]. Blue bars mean on-gassing, green bars mean off-gassing. If you see a red bar, this tissue is over-saturated (> 100%).

Tissue saturation (M-Values)

Tissue saturation (M-Values)

The deco calculator supports OC (open circuit) and CCR (closed circuit rebreather) dives with air, nitrox and trimix. Here you can see a CCR dive and bailout with air:

CCR dive with bailout

CCR dive with bailout

Current limitations and facts you need to know:

  • No repetitive dives! Every dive is calculated isolated and previous dives and tissue saturation are not taken into account!
  • No altitude diving! Every dive is calculated at sea level
  • The calculated data will differ from the data displayed on your dive computer during the dive! This is because of different algorithms, parameters, other influences and limitations
  • The current deco calculator is BETA. If you find any problems or errors, please let me know!
  • The changes you make to the gas mixtures are just for simulation. No changes will be made to your stored logbook data
  • Supported dive types: OC (open circuit) and CCR (closed circuit rebreather) with air, nitrox or trimix
  • Supported deco algorithms: Bühlmann ZH-L16A, ZH-L16B and ZH-L16C (default)
  • Gradient factors can be used for conservatism adjustments
  • Bühlmann 1b values are being used

This data will be calculated:

  • Tissue saturation (ppN2, ppHe, M-Values)
  • NDL (no deco limit)
  • Ceiling (deepest deco stop)
  • Stop time of deepest deco stop
  • CNS (central nervous system oxygen toxicity)
  • OTU (oxygen toxicity unit)

Disclaimer (full version included in application):

  • Do not use this calculator to plan real upcoming dives
  • Always compare the results with other applications and dive computers
  • You use this application at your own risk
  • Use a dive computer when you go diving

Diving Log intermediate update 2

Saturday, November 19th, 2011

Today you can download another update, which brings some great new features:

  • Gas switch profile for printing
  • Signature support
  • Automatic update check
  • Improved DiveSystem + Liquivision imports
  • Many small improvements and bug fixes

You can now add the gas switch and warning graphic to your print layout using the report designer. Just double click in the report designer any existing profile or add a new profile and change the type to “Gas” or “Warning”. You may also want to adjust the FontScale property and disable the axis labels.

Gas switch + warning lines in the report designer

Your buddies can now sign your dives on the PC in the signature window using the mouse, a touch screen or a pen. It works best with a special pen for touchscreens, but you can also use your finger and if you don’t have a touchscreen you can use the mouse to create a graphical signature. Just click the signature control in the logbook window to open a resizable popup window and sign this dive.

Click on the signature control...

...to sign a dive with your finger, pen or mouse

Diving Log checks now every 30 days if there is an update available and notifies you on startup. If you don’t want this automatic check, you can disable it in the update check window (menu Help > Check for Updates). Only official updates will show up, so beta updates like this one won’t be recognized. This function is mainly to avoid people using really old versions. Those of you reading this blog probably won’t ever see this update notification, because you update before the next check anyways. But I recommend that you keep this setting enabled.

Update available

Here you can disable automatic updates

Before you download this update, make sure you have already version 5.0.5 installed, otherwise update first to that version. Then download this zip file and extract it into the Diving Log program folder (this is not an installer, just copy the content of the zip file into the Diving Log folder).

Diving Log 5.0.3 released

Thursday, May 26th, 2011

After five month of development and five beta versions, the final version 5.0.3 is now available (install the update from 5.0.2 to update from any beta 5.0.3). For those of you, who have been downloaded and installed each beta version, there are just a few changes since the last beta. But those updating from version 5.0.2 will get a really big update with tons of new features, which would normally justify a new major version:

This update is a big improvement for technical divers and scuba divers with lots of new data fields including Nitrox, Trimix and Rebreather dives!

Changes from Beta to Final

Wednesday, May 25th, 2011

The final version 5.0.3 will be released shortly and I want to show you the few things which have been added since beta 5. It’s mostly polishing, some minor bug fixes and the German localization (other languages will follow during the next weeks). I’ve updated the Suunto Dive Manager (SDM 4.0 not yet supported!), Oceanlog, Mares Iris/Drak and UDCF import and there is a new import from the Atomic Cobalt logbook software. You can also display now in CCR dives the ppO2 chart from all three O2 sensors (if supported by the O2 monitor):

Display up to three ppO2 Sensor values

Blue is sensor 1, green is sensor 2 and cyan is sensor 3. The yellow line is the setpoint. The dive site dialog has now a 2nd page with some more data:

Dive Site Details

New profiles and CCR features

Tuesday, May 3rd, 2011

You can now import and manage your CCR dives with Diving Log. Switches from diluent to bailout (including changing the diluent and/or bailout gas) are supported, as well as ppO2 recording from up to three O2 sensors, setpoint, OTU and CNS profile data. Additionally, if supported by the dive computer, deco ceiling, NDL and stop time could be imported and displayed.

Deco ceiling, NDL and stop time

On the screenshot below you can see the ppO2 profile recorded from the O2 monitor, the yellow setpoint line (in the ppO2 profile). After 30 minutes you notice the switch to bailout and at the end another switch of the bailout gas. Switches of the diluent gas are also supported.

CCR dive profile

OTU and CNS profile

You can enter your rebreather diluent / O2 tank and all bailout tanks within the tank management dialog. Select the CCR option for the diluent and O2 tank and the OC option for the bailout tanks.

Tank Management

CCR profile data is automatically imported from APD (copy/paste), BFT, ProLink, DR5, HS Explorer, Liquivision X1, Poseidon and Shearwater. If you notice any problems or wrong data after the import, please let me know.

SAC Rate Calculation

Sunday, April 3rd, 2011

Calculating the correct SAC rate for a dive sounds like a trivial and straightforward task, but if you want to do it right, you quickly get to some hurdles. SAC means “Surface Air Consumption” or for all German readers it’s the AMV = Atemminutenvolumen. The formula is indeed very simple:

MetricSAC = (TankPressureDiff * TanksizeLiter) / (Divetime * (AvgDepthMeter / 10 + 1))

ImperialSAC = ((TankPressureDiff / WorkingPressure) * TanksizeCuFt) / (Divetime * (AvgDepthMeter / 10 + 1))

So where is the problem, you think? Well, you have to consider:

  • Is there a dive profile? If so, I can calculate the average depth and dive time from the profile. If not, the average depth must be entered manually. Before calculating the SAC rate, I have to check if all required data is available
  • Metric or Imperial calculation?
  • Double tanks? If so, multiply tank size with 2
  • Now it’s getting complicated: Does the dive have multiple tanks? If not, we can calculate right away and that’s how it worked in the past. But now since Diving Log supports multiple tanks it’s getting a lot more difficult:

If a dive has multiple tanks, the only way to calculate a correct SAC rate for the whole dive is by calculating the separate rates for each tank and then the average. So now Diving Log will calculate the dive time and average depth for each tank by running through the dive profile. When completed, it will calculate based on these values the separate SAC rates for each tank and then the average rate for the whole dive. Look at this dive for example (all metric values):

Profile with multiple tanks

You can see the SAC rate for each tank in the tank window

So SAC rate calculation for dives with multiple tanks works only if a dive profile is available and when each tank is assigned to a part of the profile. Each dive can have up to 10 tanks. In a logbook with 1000 dives, each dive 10 tanks, Diving Log will have to calculate the SAC rate for 10000 tanks when creating the SAC rate chart below. Some dive computers record the profile with a 1 second interval, so you could imagine the amount of required calculations to create this chart:

SAC Chart

The improved SAC calculation will be available in the next beta.

Version 5.0.3 Beta 2 available

Wednesday, February 23rd, 2011

You can download a new beta version which imports tank and gas information from HeinrichsWeikamp DR5 and Uwatec (Scubapro) Smart and Galileo devices. The upcoming Galileo Trimix update is not yet supported, if you have any Trimix dives on your Galileo, please send me some SmartTrak logs. You can find the download links at the bottom of the beta release post.

Version 5.0.3 Beta 1 available

Monday, February 14th, 2011

Today you can download the first beta of the upcoming version 5.0.3. There will be more beta releases in the following weeks, because version 5.0.3 is a big update with many changes in the database logbook format. Before downloading and installing, please read these important comments:

  • This is a beta, so it could crash and probably contain bugs
  • Please backup all your logbook files, before installing this beta! During the first app launch, your logbook file format will be updated. After this update, it can no longer be edited with any previous Diving Log version (including 5.0.2). So if you ever want to downgrade to an older Diving Log version, you will need your backup! If you try to edit the new logbook format with an older Diving Log version, the application will crash!

Known issues / limitations:

  • Only the OSTC downloader currently imports gas and tank switch information automatically.
  • CCR is currently not yet supported
  • Exporting, printing and statistics make not yet use of the new data
  • SAC calculation works not yet correctly with multiple tanks and double tanks
  • Deleting tanks, which are already used in the dive profile, will cause drawing issues. You have to reset the whole gas switch data for this dive and add the switches again.

What’s included in this beta:

Extended Layout 2

Remember, you can add any button to the quick access toolbar, so it's just one click away

Download Links:

I hope you enjoy the new features and please provide feedback, especially if you see any crashes or problems (including usability issues). Thank you!

Diving Log gets support for technical diving

Saturday, February 12th, 2011

This was recently the most requested feature and I know it has taken far too long, but finally it is finished: multiple tanks, gas switches, double tanks and everything you need to log your technical dives. On Monday you’ll be able to download a first beta version. The implementation of these features was not easy, because Diving Log has to fit for a wide range of divers – from the very beginner to the experienced technical diver. I think these things are nicely implemented and I hope it was worth the long wait.

In the first beta, going to be released next Monday, tank and gas information will be automatically imported from OSTC dive computers. Other import or download functions are not yet updated, but I’ll revision every single one for the next beta and try to import as much information as possible. The following screenshot shows a dive with several gas switches simulated on an OSTC and then imported into Diving Log:

Dive with several gas switches

You can see in the screenshot above that a lot has changed in the profile tab of the ribbon. You can add gas switches manually to your existing dives (or if the import of your dive computer is not yet able to import them automatically):

Add Gas Switch

Add Gas Switch

Right click on an existing switch to delete it:

Delete Gas Switch

To manage your tanks and gases, click the tank button in the profile tab on the ribbon. This window supports “auto save” functionality, which allows you to quickly edit every tank and even close the window without having to click the save button a single time:

Tank and Gas Management

CC Rebreather functionality is unfortunately not yet implemented, but I will start working on that right after the first beta release. I want to thank everyone for patiently waiting for quite a long time for this feature! I hope that these things are well implemented and I would be glad to hear your feedback about it once you’ve tried it yourself.