Chronological Sorting photos in Apple Photos incorrectly

In my example the incorrectly sorted .jpg file had the correct EXIF date (15:00) and GPS location in the same timezone as the correctly sorted images. But that image from a mobile device had also GPSDateTime tag with offset (15:00+02:00) and Mojave Photos.app 4.0 seemed to calculate the time from that GPSDateTime or/and the offset so it was incorrectly sorted at 17:00. On the other hand Catalina Photos.app 5.0 correctly sorted the same freshly imported .jpg at 15:00.

FWIW different Photos versions sort differently.

Movie dates is a mess and I thought .jpg files should be OK. But just the other day I wondered why some .jpg files were sorted incorrectly but the apparent cause was that some images (from mobile devices) had a GPS datetime while the others (from DSLR) didn't and that particular Photos version used the GPS datetime (I guess in addition to the EXIF date which was correct. All files had GPS location but not all the GPS datetime) and its offset for sorting. I planned to fix the metadata but noticed that in Catalina's Photos 5.0 that was not a problem anymore IF the photos are freshly imported (I guess old Photos library keeps the incorrect sorting even in new Photos version).

Likewise, old Photos used the movie file creation date for sorting while new versions use Keys, Userdata, QuickTime tags before resorting to creation date. So just yesterday I wondered why in one old Photos backup library the movies were sorted correctly while their metadata was a mess. But it turned out that they were imported years ago with that old sorting algorithm. Re-importing such movies to a new Photos version put them in totally incorrect order.

There should be an easy-to-use GUI to semi-automatically and manually sort such misbehaving images and movies and save that info to the metadata (IMHO also to the originals after asking the user if that is OK).

If you take photos with the same device at the same location at the same time, but some photos are tagged with GPS and some not, Photos may interpret the time stamp of the photos with GPS differently from the time stamp of the Photos without GPS. Photos is taking the GPS location as clue to the timezone of the date. If no GPS is present it may be using the timezone of current system time when we import the photos or videos.

I have changed the date and time format in the System preferences, so I can always see which time zone is attached to a date&time, when I compare two dates:

See: How to display the Date and Time Zone in … - Apple Community

It s easier to check the correct sorting, when I can see all dates and times with the timezone suffix:

Where did these photo originate? Did they all come from one iPhone? (Those should sort well.) Two or more cameras and phones? Were they all taken in the same vicinity, or across multiple time zones?

Some people see similar issues when they import photos from multiple devices, due to mis-set times on their cameras, cameras set to different time zones, or importing photos without recorded time zones into a computer located in a different time zone than the one in which the photos are taken. Most of these disordering are on the order of a few hours or a day, but they can be larger.

It is encouraging, that Photos 5 on Catalina is now giving better results.

Previously, when I have been exporting photos, editing them, then reimporting, the timezones had been frequently messed up and set to my home time zone. This is now no longer happening on Catalina. After reimporting I am now getting the same date and time as before.

It seems it was the combination of the following tags that confused Mojave Photos.app 4.0.

Normally this EXIF tag should dictate the date in images. Local time should be used in images but for some strange reason it was decided that UTC should be used in movies (and many devices lacking a timezone setting shoot movies in local time anyway...):

[ExifIFD] DateTimeOriginal : 2014:06:22 17:01:32

Then there might be also GPS time (it is not precisely the same as UTC time):

[GPS] GPSTimeStamp : 15:01:27.61

GPS location seems to sometimes add its own offsets to the time calculations in some viewers:

[GPS] GPSLatitudeRef : N

[GPS] GPSLatitude : 52.5163

[GPS] GPSLongitudeRef : E

[GPS] GPSLongitude : 13.3781

Mojave Photos.app 4.0 Get Info panel displayed all times correctly but sorted them incorrectly. Inside an album images could be sorted correctly when sorted by title (I use YYYY-MMDD-hhmm-ss format in filenames).

There are a lot of other date tags, too. With images exported from Lightroom 6.14 I occasionally have to rebuild apparently correct metadata with GraphicConverter before Photos.app or Google Photos can display the correct time.