Dates - Subject Created and Image Digitised

[GeoffA]

Just wondering how I change the settings to allow me to put just the year for Subject Created and Image digitised. Nearly all of the photos we are adding are historical photos that have been digitised.

[Mario]

This won't work. Such incomplete or uncertain dates don't play well with metadata standards, date and time formatting, File Windows, the Timeline, Events, sorting, searching, filtering etc.
Not worth the trouble, really.

The typical way to handle this is to use dates like

YEAR:01:01 if you really don't know more than the year.
YEAR:06:01 If you want to record "first half" of YEAR
YEAR:07:01 If you want to record "second half" of YEAR

Then use a metadata field, category, collection or Attribute to record that the file has an uncertain date.

This allows you to use standard dates which play well with all related features in IMatch and IMatch Anywhere and other software. And you still know which files have only uncertain dates.

See Working with Uncertain Dates for more info.

[medgeek]

Digital cameras record the date and time accurately if the camera's settings are correct. Many people find it helpful to rename their files according to the date or time taken, or both.

If you do the same for your scanned/digitized photos, you can use some of the naming conventions outlined in the Library of Congress Extended Date/Time Format (EDTF) Specification (https://www.loc.gov/standards/datetime/). These won't work for standard metadata date/time fields but they'll enable chronological sorting of digitized files by the operating system.

[jch2103]

Thanks for posting this; I'd only seen the earlier draft. The interesting question for IMatch (and other photo) users is which metadata tag would best be used for this extended date/time information. Ideally it would be a standardized tag, but I don't think that's happened.

[Mario]

Such a special and rather elaborate treatment of 'uncertain' time information is probably only interesting for the library of congress and connected institutes. Other countries most likely have different library standards for this purpose. The library of congress or corresponding ISO groups are free to define their own XMP extension to deal with that. Or maybe the IPTC has already something - their specs get more elaborate and complicated with each release. May be worth a look for interested users.

I think that for the average DAM user, amateur or professional photographer, an easy-to-adopt schema as described in the IMatch help under Working with Uncertain Dates is sufficient. And it is compatible with XMP, IPTC, EXIF, IMatch and other applications immediately.

[medgeek]

Posted by: jch2103 on: July 08, 2020, 07:03:03 PM

Thanks for posting this; I'd only seen the earlier draft.

Sure--I think I got the link for the original version from one of your posts. The LOC changed some things. For example, the convention for an unknown number is now X (it used to be u).

Posted by: Mario on: July 06, 2020, 07:23:29 PM

Such a special and rather elaborate treatment of 'uncertain' time information is probably only interesting for the library of congress and connected institutes.

The whole scheme is very elaborate and a small subset is probably sufficient for individuals scanning historical or family images. For this, I only ever use the date as the time an image was taken several decades ago is usually irrelevant, and only a small subset of the date specification at that.