Date Taken
0x9003Also: DateTimeOriginal
When the photo was originally captured.
DateTimeOriginal is the moment the shutter fired, written as 'YYYY:MM:DD HH:MM:SS'. It is the most trustworthy timestamp because, unlike file dates, it does not change when the file is copied.
Related tags include DateTimeDigitized (when it was recorded to a card) and DateTime (last modified).
There is no time zone in it. The value is the camera's local wall clock, so a photo taken abroad sorts incorrectly against one taken at home, and two cameras on the same shoot disagree if either clock was wrong. OffsetTimeOriginal (0x9011) carries the zone, but only newer bodies write it.
Want to see this tag in your own photo? Open the EXIF Viewer and drop an image — every tag is decoded in your browser. To take this tag back out again, remove the EXIF data losslessly.