Timezone Correction

[donrush]

I noticed in DiveLogDT I can add the GMT offset for a given country. For example Thailand is +7. Is there a way to get the app to convert the dive time with the GMT offset since my dive computer was set to my home time?

[support]

Unfortunately not. We always defer to the dive computer as "the truth" and want to always faithfully reproduce what it says. Having said that though, we have had a request before to be able to take a selection of existing dives in the logbook and have some sort of popup where you could adjust the time of all by "X hours or minutes". This would handle your situation nicely.

So this is on our list of "Things To Do". Unfortunately we don't have a time line for when it will be available. So in the mean time, you will have to modify the Start Time manually for each dive by editing them one by one.

Let us know if you have any questions.
Janice

[plinss]

Rather than an "adjust time" control[*], I'd much rather it actually tracked the time zone of the computer and the dive site, doing conversions as necessary.

For example, I'm primarily a travel diver so I just keep my computer set to UTC, if I dove primarily locally I expect I'd just set it to the local time zone. So a single setting (maybe with an override during download) to set which time zone the computer is set for (maybe just convert to UTC during import and store that). Then each dive can use the time zone offset of the site to display the dive times in site local time.

[*] a control to shift the time would still be useful for when the computer's clock was off.

[support]

Rather than an "adjust time" control[*], I'd much rather it actually tracked the time zone of the computer and the dive site, doing conversions as necessary.

We do in fact do this for dive computers that support it. For example, most UWatec computers keep UTC time and then the users just set the UTC offset of the place they are diving. And we use that to figure out the time of the dive. I would say that most brands though just deliver a number for the day/month/year etc of the dive. So there is no way to know what time zone the dive took place in.

For example, I'm primarily a travel diver so I just keep my computer set to UTC,

I think your's is a unique use case. I think most manufacturers expect and most divers do set their dive computers time to the local time where they are diving. *Especially* those that travel to dive. Since almost all of them show the "time of day", most people want that to be the "local" time of day, not the time of day somewhere else - home or otherwise. Certainly we've all forgotten to change the time on our dive computers before the first dive of a trip at one time or another, but this is considered a "mistake" and not practice. I'd guess that you keep yours in UTC time so that you don't have to remember to set it before each 1st dive of a trip. I have just recently seen some new models where you can have 2 separate times set so you can have both local time and "home" time displayed on it, but again, this is fairly new.

I've found that most other logbook software will use the timezone of the desktop computer to adjust the time of a dive. Again, especially for people that travel to dive, this makes no sense and so we try really hard not to do that. We only do it for older UWatec dive computers that don't support reading the UTC offset. Right now we are adding support for a new brand of dive computer that uses a UTC-ish time, and we are not able to decode what the UTC offset setting was for the dive (no word from the manufacturer), so we had to add a "UTC offset" adjustment after Download, and before Importing to accommodate it. But this is the first brand we've had to do that for as we have been able to get the "right" time for everything else.

We'll try to get the feature mentioned in a previous post done sooner (adjust "Start time" by X hours and Y minutes for multiple dives). That seems like the best way to accommodate your particular use case and is a more general method for everyone. As you've noted, it will essentially do what you need, just one step *after* Downloading as opposed to *during* the Download process.

Let us know if that won't work for you,
Janice

[plinss]

Rather than an "adjust time" control[*], I'd much rather it actually tracked the time zone of the computer and the dive site, doing conversions as necessary.

We do in fact do this for dive computers that support it. For example, most UWatec computers keep UTC time and then the users just set the UTC offset of the place they are diving. And we use that to figure out the time of the dive. I would say that most brands though just deliver a number for the day/month/year etc of the dive. So there is no way to know what time zone the dive took place in.

Cool, so you already have the support, you just need to expose UI for it. What I was requesting is some UI during the download to pick the time zone for those computers that don't supply the information.

For example, I'm primarily a travel diver so I just keep my computer set to UTC,

I think your's is a unique use case. I think most manufacturers expect and most divers do set their dive computers time to the local time where they are diving. *Especially* those that travel to dive. Since almost all of them show the "time of day", most people want that to be the "local" time of day, not the time of day somewhere else - home or otherwise. Certainly we've all forgotten to change the time on our dive computers before the first dive of a trip at one time or another, but this is considered a "mistake" and not practice. I'd guess that you keep yours in UTC time so that you don't have to remember to set it before each 1st dive of a trip. I have just recently seen some new models where you can have 2 separate times set so you can have both local time and "home" time displayed on it, but again, this is fairly new.

I'm not sure how unique I am. While I understand many computers also serve as a watch, mine doesn't do that well enough to make it worth it. First, it's puck-sized so not something I generally walk around with (except during surface intervals), and second, you have to push several buttons to display the time. So it's far more convenient to simply keep it in UTC and never have to worry about updating the time.

I've found that most other logbook software will use the timezone of the desktop computer to adjust the time of a dive. Again, especially for people that travel to dive, this makes no sense and so we try really hard not to do that. We only do it for older UWatec dive computers that don't support reading the UTC offset. Right now we are adding support for a new brand of dive computer that uses a UTC-ish time, and we are not able to decode what the UTC offset setting was for the dive (no word from the manufacturer), so we had to add a "UTC offset" adjustment after Download, and before Importing to accommodate it. But this is the first brand we've had to do that for as we have been able to get the "right" time for everything else.

Yeah, using the timezone of the desktop would generally not help at all. Using the timezone of my iPhone might be useful, but I don't always download the log until I return home and it's no longer in the same time zone as the dive took place. So simply being able to tell the software which time zone the computer was set for would be ideal.

We'll try to get the feature mentioned in a previous post done sooner (adjust "Start time" by X hours and Y minutes for multiple dives). That seems like the best way to accommodate your particular use case and is a more general method for everyone. As you've noted, it will essentially do what you need, just one step *after* Downloading as opposed to *during* the Download process.

Let us know if that won't work for you,
Janice

The adjust time would be more useful for when the clock in the computer is simply off (so long as you can select a set of dives to apply it to). The clock in my computer does tend to drift after a few months.

[support]

Cool, so you already have the support, you just need to expose UI for it. What I was requesting is some UI during the download to pick the time zone for those computers that don't supply the information.

So far, except for older UWatec, there are no manufacturers/brands/models for which we need this UI as the correct offset is always available or it's value is "not applicable". My preference is to *not* need this UI unless absolutely necessary. The next release of DIveLogDT will support a new manufacturer, and it's the first one where this UI will be required.

What brand/model of dive computer do you use?

The adjust time would be more useful for when the clock in the computer is simply off (so long as you can select a set of dives to apply it to). The clock in my computer does tend to drift after a few months.

No, this would be for when you want to apply a bulk time change to the dive start times. Which is exactly what you're doing when you download dives and apply a UTC offset to the start time. I took a look at this feature after our discussion and it was pretty straight forward. So it's been implemented and will be in the next release.

And second, if you're using our software you must be on a Mac. And if you're seeing that much drift in your Mac's clock, I suggest you make sure you're running with a time server. If you open your System Preferences, and click the "Date & Time" button, there is a checkbox to "Set date and time automatically" that you should click. And next to it, just pick your closest Apple Time Server which is probably the default, eg: apple.time.com. This will keep your Mac's clock from drifting "too much".

Janice

[plinss]

Cool, so you already have the support, you just need to expose UI for it. What I was requesting is some UI during the download to pick the time zone for those computers that don't supply the information.

So far, except for older UWatec, there are no manufacturers/brands/models for which we need this UI as the correct offset is always available or it's value is "not applicable". My preference is to *not* need this UI unless absolutely necessary. The next release of DIveLogDT will support a new manufacturer, and it's the first one where this UI will be required.

Unless the user forgot to adjust the time zone in their UWatec, so the correct time zone may not always be available. And frankly, for dive computers without time zone support, it's not "not applicable" as they all are set to some time zone, you just don't know which one. It might be the correct time zone of the dive, or it might not. So I really don't understand why this is controversial. In general its better for software (especially logging software) to store times internally in UTC and be able to apply time zone offsets at display time (maybe people want to see their dive times in different time zones than the dives took place in to compare to someone else's experience), knowing how to convert the dive computer time to UTC is a feature.

Also, while having cluttered UI is bad, exposing options to your users is a good thing(tm), so please don't resist allowing your users to use your software in modes that you may not have anticipated or don't consider ideal from your perspective (as others have different perspectives and needs).

What brand/model of dive computer do you use?

Aeris A300.

The adjust time would be more useful for when the clock in the computer is simply off (so long as you can select a set of dives to apply it to). The clock in my computer does tend to drift after a few months.

No, this would be for when you want to apply a bulk time change to the dive start times. Which is exactly what you're doing when you download dives and apply a UTC offset to the start time. I took a look at this feature after our discussion and it was pretty straight forward. So it's been implemented and will be in the next release.

And second, if you're using our software you must be on a Mac. And if you're seeing that much drift in your Mac's clock, I suggest you make sure you're running with a time server. If you open your System Preferences, and click the "Date & Time" button, there is a checkbox to "Set date and time automatically" that you should click. And next to it, just pick your closest Apple Time Server which is probably the default, eg: apple.time.com. This will keep your Mac's clock from drifting "too much".

Janice

It's not the clock in my Mac that drifts, it's the one in my dive computer that does, sorry I wasn't more specific.

[support]

Also, while having cluttered UI is bad, exposing options to your users is a good thing(tm), so please don't resist allowing your users to use your software in modes that you may not have anticipated or don't consider ideal from your perspective (as others have different perspectives and needs).

You are quite right. Which is why in the next release you will be able to do what you request. Albeit not on a Download panel, but after downloading as part of a more general UI on the Dives panel. So you can select any number of Dives and Adjust the Start Time, plus or minus, any number of hours and minutes. So if you keep your DC in UTC time, then after downloading them you can select them, and then do a "- 8 hours" adjustment on them all. But also, if a user just forgot to set their DC to local time for their first 1 or 2 dives, they can just select the 1 or 2 and do the same thing. For you, this will admittedly be a 2 step process that you'd prefer to see in 1 step. But it will be a heck of a lot better than having to manually edit the start time for each individual dive after the fact!

Aeris A300.

So yes, for the Pelagic family of dive computers, there is no notion of a time zone and we just get a number for the year, another number for the month, another for the day, hour, minute. And then another flag to indicate whether the diver is using 24 hour time, or AM/PM time. So it's very much just saving exactly what the user see's on their DC.

Janice