Q: Metadata in different time zones - nightmare

Oh well the pics from the Canon Camera were in GMT-7 while my Mac was in GMT+2 when I imported the pics, and the time zone depicted was LA, not Brussels where my Mac was, after hollidays

Dear,

there are apparently programs to change "Time Stamps", Exif, Creation Date, Modification Date etc, but is there also a program (or way) to change the "time zone" of a file? If I can do that, my problem is solved (I hope)

Have a nice weekend,

Erik.

The timezone setting for the camera can be written to the Exif.Image.TimeZoneOffset tag.

http://www.exiv2.org/tags.html

You can probably use exiftool from the Terminal to change this tag before you import the photo to Photos, if your camera does not set this tag.   ExifTool by Phil Harvey

I have used exiftool to change the lens tags for older cameras, but not yet to change timezone tags.

thanks again Leonie,

it will probably work, but looks quite complex

any more user friendly programs - or better something like "exiv for dummies"? That would better suit me.

Greetings,

Erik.

Dear Léonie,

I did some more investigation and you are right, the time zone of the photos is the time zone your computer is in when importing the photos, except for some pictures.

I found out that :

1. You get the adaption of time zone also for pictures you import from a folder (e.g. pictures that were exported before), which almost solves the complete circus. Only problem : if you travelled trough more than 1 time zone when you took pictures.

2. I have in my holiday 2015 album, 3 different kind of photos :

- taken with Canon camera - while under GPS coverage

- taken with the same Canon camera - while NOT under GPS coverage (poor or no signal at time of photo)

- taken with iPhone6 camera

The pictures which were under GPS coverage, do not have the phenomena of adapting the time zone to the time zone of your computer during import. These pictures have the correct time zone.

3. I thought to have found a solution, and in Photos 1.3, I added a GeoTag to all my pictures without GPS info. Then I exported the pictures and I checked the Metadata : The GPS info was still there (good news - it means that Photos adds these changes to the Metadata of the Photo - which it does not with the time zone you change manually). I imported the pictures again in another Mac and, the GeoTag still showed California, but the timezone changed again to Brussels = My Time zone.

For info : Result of my test : I will add here info from 3 files (2 pictures) :

- 2074.jpg : with GPS coverage

- 2075.jpg : without GPS coverage with manual added Geotag

- 2075 original.jpg : without GPS coverage and no added GEOtag

In Green you find what the 2 first have in common but not the 3rd / in Yellow you find the info only the first one has (especially altitude and gps time)

When importing these files, the 2074 results in an automatic Time Zone to California, while the 2075 (with added GeoTag) results in time zone of computer while importing. Although on all pictures you find "time zone not specified". So what could result in a time zone for the first picture? The GPS time??

So I have a 3 new questions :

1. On which parameters does PHOTOS decide to put the Time Zone?

2. What about the daylight saving time? Most time zones in the world have 2 time zones : e.g. Brussels : Summer = GMT+2 / Winter = GMT + 1

3. Can an iPhone not add a Geotag? They claim it has a GPS, but I find no GPS info on any iPhone picture - or do I have wrong settings?

Thanks,

Erik.

A great summary, Erik, thank you. The GPS effect must be new in El Capitan. I have not seen this in Photos on Yosemite.

The pictures which were under GPS coverage, do not have the phenomena of adapting the time zone to the time zone of your computer during import. These pictures have the correct time zone.

When I import pictures taken with GPS it is even worse for me.  Photos treats these pictures like the camera had been set to the time zone of the place where the photo has been taken.  Which is worse.

Most of the iPhone imports are incorrect, because I never enable the cellular network for the iPhone when traveling abroad. So the photos have GPS, but the time stamp may be from a different timezone, because the timezone will not be set automatically when crossing the border.

And all timestamps for photos from my digital cameras are always wrong, GPS assigned or not, because I never ever change the clock from UTC in the cameras. I want a continuous timebase for all photos, without a the added daylight saving time complication. So the times in Photos will only be correct, when I am visiting Great Britain in winter.

A few years ago, whenI visited Alaska and Yukon Territory, and crossed continually the border between Canada and Alaska, it was nearly impossible to keep the dates right after importing the photos. All this would be easier, if Photos were showing the dates with the timezone in the Info panel.

If I force the date to show the timezones by changing the date format in the System Preferences, Photos will ust append the current system timezone name to the time, without converting it. It will just allow for daylight saving time:

The Info panel in Photos with the System Time set to GMT+1 when browsing the photos:  The Photo has been taken in Alaska, after crossing the border to Yukon, and the iPad was still set to Yukon time.v  So the correct time was 16:51 Yukon time.

And with the system time set to Yukon time when browsing: Photos is changing the name of the timezone, but not converting the time.

Dear Léonie,

When I import pictures taken with GPS it is even worse for me.  Photos treats these pictures like the camera had been set to the time zone of the place where the photo has been taken.  Which is worse.

At least we should be able to use or not this option. Because for me this is an advantage, since these are my only pictures with the correct info (time/date/position/ time zone etc.) + Photos puts them in the right order : e.g. a picture in Brussels at 11AM comes before a picture in New York at 6AM, which is correct, though 11>6.

I just found out why my iphone pics didn't have gps position (http://osxdaily.com/2010/07/06/get-iphone-photo-gps-geolocation-data/), though same problem as with the Canon camera, the GPS is not always available. And so when not available it takes the time zone of the computer + the time of the camera, but then 2 pictures in the same time zone, one with and one without GPSinfo, downloaded to the computer in a different time zone results in a time difference of "time zone 1 - time zone 2", which is wrong,

I really would like to know in which cases MAC PHOTOS uses the GPS info as time zone and when not. I wonder if it is not the fact of having a GPS Time or not.

Greetings,

Erik

There are occasions when iPhone images don't have GPS information and it's a problem that's really annoying me.

If you take the picture through iMessage (for example), the resulting picture saved to the camera roll is missing the following metadata. MAKE, MODEL and LOCATION.

Why this occurs, I have no idea. The original photo is stored to the camera roll while the optimised version, sent via iMessage, still has this information attached.

Apple Iceman wrote:

 

There are occasions when iPhone images don't have GPS information and it's a problem that's really annoying me.

 

If you take the picture through iMessage (for example), the resulting picture saved to the camera roll is missing the following metadata. MAKE, MODEL and LOCATION.

 

Why this occurs, I have no idea. The original photo is stored to the camera roll while the optimised version, sent via iMessage, still has this information attached.

Ok - but it is not at all clear why you posted this in the Photos for Mac user to user forum - it seems to have nothing to do with photos and no one here can change anything - can you explain your reasoning please or ask a technical question  abut Photos for the Mac that the users here can hep with?

LN

Ok - but it is not at all clear why you posted this in the Photos for Mac user to user forum - it seems to have nothing to do with photos and no one here can change anything - can you explain your reasoning please or ask a technical question  abut Photos for the Mac that the users here can hep with?

We're talking about timezone (and location) information when importing into Photos. I've had this problem before where I couldn't understand why some of my photos taken with my iPhone didn't have timezone information. It was a long process to discover where the fault lay.

The original post included references to Photos and iCloud. Bugs in the iPhone comes across to the Photos app which is advertised as the Mac software for your photos. iPhone included.

We're talking about timezone (and location) information when importing into Photos. I've had this problem before where I couldn't understand why some of my photos taken with my iPhone didn't have timezone information. It was a long process to discover where the fault lay.

Photos for Mac is still handling imports from the iPhone frequently wrong.

Other iPhone and iPad photos that will give incorrect location data and capture times are the still images, that come with iPhone videos. They are frequently imported with the wrong timezone and appear in different moments than the videos they belong to.

Also, if I sync photos with iTunes to my iPad  and edit them on the iPad, My Photo Stream will sync them back without GPS and with an incorrect time zone.

And lastly, if my iPhone and Mac cannot connect to Wi-Fi and I have to import the recent photos using a USB connection, and accidentally import an older photo that has been downloaded from iCloud Photo Library, this iCloud download  will also have missing metadata and an incorrect capture time.

Erik Coremans wrote:

 

 

2. I have in my holiday 2015 album, 3 different kind of photos :

- taken with Canon camera - while under GPS coverage

- taken with the same Canon camera - while NOT under GPS coverage (poor or no signal at time of photo)

- taken with iPhone6 camera

The pictures which were under GPS coverage, do not have the phenomena of adapting the time zone to the time zone of your computer during import. These pictures have the correct time zone.

 

 

Eric,

I am struggling with the same dilemma, as I attempt to import/process several hundred photos taken on a recent vacation trip. I've come to the same conclusion that you have re pictures taken with no GPS coverage.

Here's what I think is happening:

- if a picture imported into Photos has legitimate GPS tags (lat & long), Photos will use the GPS info to determine a "Closest City", and from that, the timezone in which it thinks the picture was taken.  It then adds the derived timezone info to the metadata for that picture.  That timezone is then used when Photos determines how to order pictures in the Moments timeline.

- if a picture does not have GPS tags (perhaps the GPS receiver in the camera was turned off), Photos is unable to determine a "Closest City". Nor can it infer the timezone in which the picture was taken.  If that's the case, it assigns the nearest city to the Mac when the import was done as Closest City (using OSX Location Services). It also appears to assign the picture with the system timezone in effect on the Mac when the import was performed.   If/when that happens, the picture will be sorted in the Moments timeline hours away from where it should be.

- I've encountered an additional scenario. Sometimes, my camera (a Lumix ZS-40) will store out-of-bounds lat/long values in the EXIF. This happens when the camera does not have good GPS coverage (i.e. inadequate GPS signals from >3 satellites).  In that situation, the Lumix also records the value "Void" in the GPSStatus tag in the EXIF, declaring that the GPS values are no good.  It appears that Photos ignores the value in the GPSStatus tag. When it imports such a picture, I've observed that it assigns no Closest City (a blank).  It seems to assign a timezone of GMT to such a picture.   When such a picture gets placed in the Moments timeline, it will also be out of order.

As for images originating on an iPhone, I've found that iOS treats pictures taken on my iPhone differently from screenshots.  Pictures may or may not have correct GPS tags (depending on if/how the iPhone was able to determine location when the picture was taken).  An iPhone may use GPS satellite signals, and/or cell tower info, and/or WiFi base station info to infer location.  The location info embedded in an iPhone picture may or may not be accurate.  On the other hand, I've observed that screenshots captured on the iPhone don't have any embedded location/GPS metadata. I've noticed that Photos assigns the location and timezone that the Mac has when a screenshot is imported into Photos.

One 'fix' for this mess is to assign correct GPS tags to all pictures before they are imported into Photos.  In your case, this means assigning location info to any pictures taken on your Canon when it had no GPS coverage.  Geo-coding can be done using a 3rd party program such as HoudahGeo. That's what I'm using.  Once that's done. you can import all the geo-tagged pictures into Photos, which will then assign a consistent location-based time zone to every picture.

As Léonie points out, this all gets much more complicated when images transit through iCloud, get synced via PhotoStream, are transferred via USB, and/or are migrated using carrier pigeon.

As Léonie points out, this all gets much more complicated when images transit through iCloud, get synced via PhotoStream, are transferred via USB, and/or are migrated using carrier pigeon.

And if the GPS data are embedded in the original Master image files before importing the GPS will survive the journey through iCloud.  It is really worth it to get the locations embedded in the originals. It makes it easier to move photos between Photos Libraries as well.

On the other hand, I've observed that screenshots captured on the iPhone don't have any embedded location/GPS metadata. I've noticed that Photos assigns the location and timezone that the Mac has when a screenshot is imported into Photos.

It's not only screenshots. It appears to be all photos not taken directly through the built in camera app, as I described in Re: Metadata in different time zones - nightmare.

Above is a screenshot of Image Capture, showing two photos taken on my iPhone, ready to be imported. The top photo was taken through iMessage, the bottom through the Camera App. There are a couple of things worth mentioning.

• Both images were taken with a valid GPS signal. Top image has more than location stripped.
• The filenames indicate that the top picture was taken before the bottom picture. Correct.
• The times indicate that the top picture was taken after the bottom picture. Incorrect.
• The top picture has adopted the current timezone on the iPhone (+9) and not the Mac, which is still on the timezone when both pictures were taken (+2).
• The photos appear in the correct order in Moments on the iPhone with the second picture's time adjusted showing as (+9).

I reported this bug and had an email conversation with a guy in the Photos section. It ran out of steam when it was determined to be an iPhone issue. That the products work hand in hand was conveniently forgotten.

One has to ask two questions. Why strip this information in the first place? Secondly if it is stripped, or there is no valid location information on the phone, use the timezone on the phone/camera when the photo was taken through TimeZoneOffset Exif data field.

Moments is an integral part of Apple's photo strategy, this is basic stuff that should have been thought through.

I just went on a trip. I have an iPhone 6s Plus  / Nokia Lumia 950 XL / Samsung S6.

I copied all my images to one folder (I use a Windows 10 computer). Below are the naming conventions of files not taken at the same time:

20160526_194646.jpg                          Android

WP_20160520_09_43_22_Pro.jpg      Windows

20160526_091035396_iOS.jpg            iOS

What I found with iOS was, the image filename is taken in GMT.

So being that my trip was 10 hours off of GMT, I would need to script out the renaming of the files to adjust for the 10 hour difference.

so this image 20160526_091035396_iOS.jpg iOS says it was taken on 2016/05/26 _ 09:10:35:396

that reads 9:10:35 AM. The last 3 numbers in Bold (396) maybe the millisecond but I didn't confirm that.

should look more like:

20160526_191035_iOS.jpg     (I removed the last 3 since I don't take pictures that quickly.

The problem still is, because my flight to my tripe was with layovers in 2 more time zones, I need to identify the images that were taken in different time zones to ensure I don't adjust 10 hours on a time zone that was different.

If people are taking photos with devices (like phones) that update time automatically from cell phone providers, this would not be an issue if the images were not saved in GMT. 

but I can also see the issue where, if you had an old digital camera, the images would all have been saved in the original time zone (Since most people don't change the time on their cameras while traveling).

I'm sure the different platforms (Windows/Apple/Google) will not agree on a standard between them to say, filenames should all be like:

YearMonthDay_HourMinuteSecond_Platform    (and potentially millisecond)

but if you know the difference for iOS and you rename all your photos to be a similar naming convention your images will sort properly.

The downside here is, while the platforms are not using a similar convention if you receive more photos, let's say the event was a wedding and person 5 decides to send you their complete images, you then have to go through the exercise again, to ensure you have images named chronologically correct.