The "Date Created" field is a Date format field with this usage description:ĭesignates the date and optionally the time the artwork or object in the image was created. not the date and time a file was created - such as the data and time of an original digitally created image. These mechanisms allow historic dates (or future dates) to be used mathematically in databases for date and time difference calculations and Time Zone adjustments without having to supply a formula to do so and are also, typically, Leap Year aware as well as having other attributes for undertaking various calculations to convert to different counting and measuring systems.įor IPTC data there seem to be at least 2 optional fields that seem to have been made available to deal with recording dates and times that are not EXIF related - i.e. Windows development has always used as far as I know. Apple, at one point, used 2 different start dates for those - or iirc. In a database one can establish date fields that work to different base dates and there are some standards for those. In effect that would just shorten the period of time that the operating system could be used before it required modification to enable it for longer operation span or a rest of the "base date" with the associated problems of dealing with old data and trying to match systems running different base dates.Ī bit like the "Year 2000" problem only more disruptive in reality than Y2K would have been.
The default UNIX operating system started from 1/1/70 since it did not exist before that date and there would be no point allowing for earlier numbers (that represent dates) that the system itself would never use. Computer date systems are constrained, in their basic state, by the size of the data fields available to store the time count as a whole number.
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