Custom xmp schema: analogexif (for scanned images)

Started by jch2103, January 13, 2015, 12:07:49 AM

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jch2103

I know there must be more background on this on the Forum on in Help, but I'm having trouble finding it.

I have been using 'unused' IPTC fields to store information for my scanned images, such as film type and film camera. However, I'd like to get away from using IPTC fields for this. I recently came across AnalogExif, which uses a custom xmp schema for storing information for analog camera film images. (See http://analogexif.sourceforge.net/help/analogexif-xmp.php)

It would seem to make sense to use an existing xmp schema rather than (perhaps) invent my own, or to continue using 'unused' IPTC tags. However:

  • How would I add this schema to IMatch so I can add these xmp tags to the metadata editor and use the tags in metadata templates (to move data between tags)? 
  • There are apparently a few other similar approaches, e.g., a LensTagger plugin for Lightroom, etc. Is one of these a better approach than the AnalogExif schema?
  • Am I missing something important/useful (e.g., using hierarchical keywords instead)? I suppose I could use, e.g., xmp exif model, but that doesn't handle other analog film data, and I'm leery of creating potential conflicts with existing digital camera data.
John

Mario

Proprietary XMP schemas/namespaces must be added to ExifTool first in order to read/write them. IMatch then also supports them automatically.

It's often not worth the trouble, frankly. There are so many tags in XMP you can use to store a bit info about film and camera, creating a custom namespace for that would be overkill. If you want to learn more about this, see

http://www.sno.phy.queensu.ca/~phil/exiftool/config.html

and google for ExifTool custom XMP namespace
-- Mario
IMatch Developer
Forum Administrator
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sinus

#2
Quote from: jch2103 on January 13, 2015, 12:07:49 AM
I know there must be more background on this on the Forum on in Help, but I'm having trouble finding it.

I have been using 'unused' IPTC fields to store information for my scanned images, such as film type and film camera. However, I'd like to get away from using IPTC fields for this. I recently came across AnalogExif, which uses a custom xmp schema for storing information for analog camera film images. (See http://analogexif.sourceforge.net/help/analogexif-xmp.php)

Hi John

I am not sure, if I understand fully. I want store some informations into some xmp-fields.
For example a "custom filename-field" or a custom "Stacking-field".

In the old IM3-era ;) I used the Custom Fields from IM3. These fields we can import now, but there are not more writeable (see the last entry in my attachement).
So I have searched some xmp-fields, what I do not use for that information, what they are created for. To be honest, because these xmp-specifications are very technical and in English, I had troubles to understand.

So I took some fields, what are maybe not very good to use, but anyway, I use them.

I use for example the field "{File.MD.XMP::photoshop\TransmissionReference\TransmissionReference\0}" as a custom field for me. Then in the metadata-browser of IM5 I replaced simply the original text and wrote "Kunden-Dateiname".

You can see this in my last entries of my attachement. This is perfect for me.

The only problem is, that I am not sure, if these fields, what I do use, if these fields are good for that.
But if I discover one day, that they are not very good for use them in my manner, well ... I simply will change them with another (better) field.

The old IM3 made this easy for us, because of the custom fields 1-20 (if I remember correctly). Would be nice to have such fields here too or, I think, even better, to know several xmp-fields, what we could use for our own use without danger, thought these fields are originally created for something else. To search, read and understand these specs fully for such fields (I tried it), my English is really not enough good.

[attachment deleted by admin]
Best wishes from Switzerland! :-)
Markus

jch2103

Mario and Marcus: Thanks for the feedback.

Mario: You're probably right that trying to use a custom xmp schema is not worth the effort. There certainly lots of 'unused' xmp tags that could be used for miscellaneous information. It's also apparent that most of the xmp schemas recognized by ExifTool are from large corporate or institutional organizations, intended for specific purposes. It would seem that those interested in analog photo (i.e., scanned) images don't have the institutional clout to establish 'known' schemas. It would seem that the only folks who would have the clout to set up a schema that recognizes analog photo information (i.e, scanner hardware or software companies) have other, more critical concerns. I can understand that, while still thinking that there must be others who have an interest in this.

Marcus: For what it's worth, IMatch/ExifTool does recognize the XMP Plus schema (a digital rights system (http://www.useplus.com/), which includes Custom 1 through Custom 10 tags. I suppose these could substitute for the IM3 custom fields, especially as the xmp Plus tags are to be used by rights owners for licensing (and hence should be available for other kinds of images...?).
John

Mario

I'm not sure what you would put into the custom XMP schema.
A scanner is able (and should) fill in a proper EXIF record so you can record all technical details. A modern scanner should instead write an XMP record with suitable EXIF information. But, frankly, most scanner/software does not bother at all.

To store analog details like film type, camera, development process etc. you can choose one of the description tags, or use keywords or whatever fits. If this information is only for you, you are completely free in your choices. Otherwise, check with your clients or circles to setup some agreement about what to put where.

ExifTool supports many proprietary XMP schemata, not all from big vendors. But there have to be more than a couple of dozen people to be interested in a custom namespace before Phil considers spending time setting up support for it. At this time, IMatch/ExifTool support 48 (!) XMP namespaces.
-- Mario
IMatch Developer
Forum Administrator
http://www.photools.com  -  Contact & Support - Follow me on 𝕏 - Like photools.com on Facebook