1

I have a bunch of photos I took with my DSLR. It does not have GPS, so I geo-tagged all the photos using GPS positions I captured on my phone. This part works fine. However, when I upload them to Google Photos, it is saying they were taken in the time zone the GPS coordinates are in, but my camera clock was set to a much different time zone. I suspect this is because it is (wrongly) assuming that the time zone the picture was taken in (the GPS position) is the time zone the clock is in.

At this point, I'm not sure what the easiest way to fix this is. All my photos have multiple places that the timestamp is in, including the file name. And, my image library by convention uses my home time zone for everything, therefore if I were to change the time of the photo to be in a different time zone it would get confusing.

I have seen this question as well as this one which tell me that there is no way to set the time zone in the EXIF tag. How should I proceed here?

Michael
  • 791
  • 1
  • 10
  • 20
  • 2
    As xiota says, the EXIF date/time tags are supposed to be set to the local time and Google is correctly interpreting the date/time and the local time zone. You cannot expect Google to show the correct info when you are providing incorrect data. The only way to "fix" this is to remove the GPS coordinates. In my testing, Google will give priority to the time zone for the coordinates over even if the time zone is set elsewhere. – StarGeek Oct 22 '22 at 15:33

2 Answers2

3

I have seen ... which tell me that there is no way to set the time zone in the EXIF tag. How should I proceed here?

The most expedient solution is to change the date-time tag to the local time of the location in which they were taken.

Per StarGeek (1, 2):

As of EXIF standard 2.31 (2016), the EXIF standard includes 3 tags to record the time zone. There is OffsetTimeOriginal which is the time zone for the DateTimeOriginal, OffsetTimeDigitized for the DateTimeDigitized (which is CreateDate in exiftool), and OffsetTime for the DateTime (ModifyDate in exiftool).

In my testing, Google will give priority to the time zone for the coordinates over even if the time zone is set elsewhere.

xiota
  • 26,951
  • 4
  • 39
  • 126
  • 2
    As of EXIF standard 2.31 (2016), the EXIF standard includes 3 tags to record the time zone. There is OffsetTimeOriginal which is the time zone for the DateTimeOriginal, OffsetTimeDigitized for the DateTimeDigitized (which is CreateDate in exiftool), and OffsetTime for the DateTime (ModifyDate in exiftool). I believe Google will read these but will give priority to the time zone of the GPS coordinates. – StarGeek Oct 22 '22 at 15:25
  • 1
    @StarGeek I noticed there was already a different EXIF tag "TimeZone" set correctly, even with it and all the Offset tags you mentioned you are correct, Google stupidly ignores all of them and thinks it knows better what time zone the time is in. Guess I'm going to have to write a script to change a few hundred date-time tags... – Michael Oct 23 '22 at 04:44
  • As a preliminary test it appears that changing DateTimeOriginal (via exiftool) to match the time zone is sufficient for Google to recognize the correct time. – Michael Oct 23 '22 at 05:20
  • Ugh. This is going to be tricky because some pictures I don't know the timezone (they were taken from an aircraft) – Michael Oct 23 '22 at 14:48
  • Wow this is an ugly problem. There isn't even any guarantee that a given coordinate will remain in the same timezone offset. For instance, what if in the time between capture and processing the photo "daylight time" starts or ends? Political change means that the offset could change, and different political entities may not even agree on the timezone of a given point at a given time (according to one lat/lon to timezone library I looked at). How does Google handle this? Am I forced to use their API for lookups? Will my times "break" in the future? – Michael Oct 23 '22 at 15:05
  • FWIW, Google hardware doesn't even get this right. In addition to my DSLR, I also took a bunch of pictures with my Pixel phone... when they uploaded to Google Photos they were all out of order because there was no network connection to change the timezone each time the device cross a timezone boundary but they DID have GPS coordinates. – Michael Oct 23 '22 at 15:12
  • @Michael With exiftool, make sure you're using the command in FAQ #3 to look at the tags. TimeZone is almost certainly a proprietary MakerNotes, i.e. Camera specific, tag. It will have a Group name of Canon/Nikon/Panasonic/etc. Google will almost certainly never read such tags, as every camera company uses different formats for MakerNotes tags. The OffsetTime* tags are part of the EXIF 2.31 spec and the cameras on newer phones will use these. DSLR cameras, not so much, as they are less aware of time zones. – StarGeek Oct 23 '22 at 16:06
  • @StarGeek If DateTimeOriginal is expressed in the timezone the GPS position in from, then Google displays the time correctly. But you're right, there's an additional complication that the proprietary TimeZone tag is probably now incorrect - but I'm not 100% sure it's relative to DateTimeOriginal and not something else. I suppose I'll leave it along unless I happen on something else that breaks in its presence, in which case it will be a great amount of work to go back and reprocess everything to fix this tag. Perhaps I should just delete it... – Michael Oct 23 '22 at 23:38
  • Here's a post on the exiftool forums where I give an example of how the MakerNotes TimeZone works, at least in Canon and Nikon cameras. – StarGeek Oct 24 '22 at 15:55
2

You can manually change the date and time for the photos after uploading to google photos (under the info tab). Then your local library and Google Photos will have the same date/time organization, while also leaving the GPS coordinates intact/correct.

enter image description here

Steven Kersting
  • 17,087
  • 1
  • 11
  • 33
  • 3
    Ah, good point. So used to dealing with the data in the files I forgot about editing on the website. Though that can be a big task if there are hundreds or thousands of files. – StarGeek Oct 22 '22 at 20:39