-time:all tags and their (un)official priority

[grasdk]

Hello

If this has been answered earlier, I apologize and will appreciate a link

Two questions:
1) Is there a complete list of tags containing date and/or time and/or offset information? I'm thinking particularly of the ones that can be returned by exiftool -time:all, but if there are even larger lists, I would be interested in that as well.

2) Is there an (un)official priority for these tags, when you're interested in the point in time a photo was taken?

I understand that DateTimeOriginal combined with OffsetTimeOriginal and SubSecTimeOriginal refers to the camera shutter close time, so it's probably one of the most precise, if not the most precise tag... but any priority on the others? Groups, and tags?

I see timestamps in many different groups, and as a group I would always prirotize file last, but inside groups and subgroups there are a lot of tags. Probably some mean the same, but are placed in different groups.

exif
iptc
xmp
xmp-exif
xmp-xmp
xmp-tiff
xmp-photoshop
<others>
file

and there are png specific tags I saw as well,

Any insights?

Thanks!

[wywh]

(un)official priority for these tags

I tested this a few months ago: macOS 14 Sonoma Photos.app reads dates in this ascending priority from .jpg (i.e. ExifIFD:DateTimeOriginal is priority 1, and time zone is read from ExifIFD:OffsetTimeOriginal):

Code Select Expand

[MacOS]         FileCreateDate                  : 2001:01:01 12:00:00-05:00
[XMP-exif]      GPSDateTime                     : 2001:01:01 12:00:00-05:00
[XMP-xmp]       ModifyDate                      : 2001:01:01 12:00:00-05:00
[IFD0]          ModifyDate                      : 2001:01:01 12:00:00
[XMP-exif]      DateTimeDigitized               : 2001:01:01 12:00:00-05:00
[XMP-xmp]       CreateDate                      : 2001:01:01 12:00:00-05:00
[ExifIFD]       CreateDate                      : 2001:01:01 12:00:00
[XMP-exif]      DateTimeOriginal                : 2001:01:01 12:00:00-05:00
[XMP-photoshop] DateCreated                     : 2001:01:01 12:00:00-05:00
[ExifIFD]       DateTimeOriginal                : 2001:01:01 12:00:00

Time zone:

[Composite]     GPSPosition                     : 40.74842 -73.98561
[ExifIFD]       OffsetTimeOriginal              : -05:00
For movies:

Code Select Expand

[MacOS]         FileCreateDate                  : 2001:01:01 12:00:00-05:00
[QuickTime]     CreateDate                      : 2001:01:01 12:00:00-05:00
[UserData]      DateTimeOriginal                : 2001:01:01 12:00:00-05:00
[Keys]          CreationDate                    : 2001:01:01 12:00:00-05:00

Time zone:

[UserData]      GPSCoordinates                  : 40.74842 -73.98561 443.2
[Keys]          GPSCoordinates                  : 40.74842 -73.98561 443.2
YMMV and the result might depend on what tag happens to come first. But I try to make those top priority tags correct and edit the less important if they happen to cause errors. In addition I insert date in the filename as YYYY-MMDD-hhmm-ss.*

- Matti

[Phil Harvey]

This command lists the -time:all tags (there are 364 of them):

exiftool -list -time:all

(intuitive, no?)

- Phil

[StarGeek]

The EXIF time stamps may have priority in most cases, but in many programs, there isn't a specific priority. Most often, the order the tags appear in the file will be used, with either the first or last tag read used as the time stamp.

Also, the File, EXIF and Quicktime tags are usually the only ones set when the file is created. Any IPTC and XMP tags are almost certainly created afterwards by a processing program.

[grasdk]

Thanks for your responses. Just what I needed