|Exif TIFF Tag DateTimeOriginal|
TIFF Tag Reference
TIFF Tag DateTimeOriginal
The date and time when the original image data was generated.
For a digital still camera, this is the date and time the picture was taken or recorded. The format is "YYYY:MM:DD HH:MM:SS" with time shown in 24-hour format, and the date and time separated by one blank character (hex 20).
When the date and time are unknown, all the character spaces except colons (":") may be filled with blank characters, or else the Interoperability field may be filled with blank characters.
The character string length is 20 bytes including NULL for termination. When the field is left blank, it is treated as unknown.