Help with settings to match keywords across IMatch and Lightroom

Started by dcb, August 23, 2023, 12:38:36 PM

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I've recently started using Lightroom alongside IMatch for the RAW/DNG develop features and I'm confused by what is happening with metadata in my files as I switch back and forth between the applications. I don't know what settings I need to change to fix the problem.

Original Match file keywords:

[XMP-dc] Subject              : Location|Australia|Victoria|Percydale|Fiddlers Creek Gold Mine
[XMP-lr] Hierarchical Subject : Location|Australia|Victoria|Percydale|Fiddlers Creek Gold Mine

I then Read Metadata in LR to update the information. Let's say I make a change to rating, save the metadata into the file (not using sidecars) and then come back into IMatch. After a rescan, the pencil icon appears and the keywords are now:

[XMP-dc] Subject              : Australia, Fiddlers Creek Gold Mine, Location, Percydale, Victoria
[XMP-lr] Hierarchical Subject : Location|Australia|Victoria|Percydale|Fiddlers Creek Gold Mine

I assume this is LR splitting the keyword hierarchy on save and then IMatch somehow not reconstructing them. Try as I may, I can't find the right settings to stop this and am ending up with many files requiring a metadata rewrite for not purpose.

All help appreciated. Thanks.
Have you backed up your photos today?


As far as I know, there is no setting to prevent Lightroom from breaking up hierarchical keywords and storing only the leaf level. What puzzles me is that it not only breaks up the keywords, but writes each individual level as a separate keyword. This is quite a mess.

I have not let Lightroom modify metadata in my files for some time (I finish them in Lr, Photoshop or other software and then add  them to IMatch). When I recall correctly, Lr used to write the leaf level element only, which makes it easy for IMatch to remap the keyword using your thesaurus. There are AFAIK no options in Lr to control any of this.

Of course your IMatch thesaurus must be properly maintained. If the keyword "Location|Australia|Victoria|Percydale|Fiddlers Creek Gold Mine" does not exist in your thesaurus, IMatch cannot map the flat keywords back to hierarchical keywords.
See Keyword Mapping during File Import

Which settings do you use in IMatch under Edit > Preferences > Metadata: Keyword Export?
The default is "Write hierarchical keywords".
In that case IMatch writes hierarchical keywords also for flat keywords, which allows for recreation of hierarchies.

Note that Lr has been criticized often for how it deals with hierarchical and flat keywords.
Interoperability is never a big thing for Adobe, customer retention is.

Google for Lightroom flat hierarchical keywords and similar to find bug reports and questions all over the web related to this.

Processing metadata with multiple applications can be a challenge at the best of times.
Managing keywords in multiple applications can become a real burden since there is no standard and all applications vary in how they deal with keywords.
This is the reason why IMatch has so many options related to keyword import and expert. And uses the thesaurus as the central feature to assign keywords and map flat keywords into your hierarchy.

-- Mario
IMatch Developer
Forum Administrator  -  Contact & Support - Follow me on 𝕏 - Like on Facebook


Hi Mario,

Since I'm introducing Lightroom into my workflow there is a lot of back-and-forth at the moment as I work out the best way to do things. That will settle down. I had not thought of doing all processing in LR before I even import into IMatch. I've just naturally used IMatch so much over the years it is my natural go-to for photos and metadata. Keeping them separate and importing only when done will definitely solve the problem above.

For the records
- I'm using the latest version of Lightroom Classic on PC
- The Fiddlers Creek location is in my Thesaurus (and I updated from @keywords to double-check)
- Write Hierarchical Keywords is on

IMatc is doing everything it should. Absolutely Lightroom is the cause of this. Now that I know I can take steps to manage it. At least nothing is "wrong" that I have to worry about.

Have you backed up your photos today?


I agree. It's a bit messy. Some applications handle hierarchical Keywords, some don't.
Some write hierarchies in flat keywords to preserve them, some write only the leaf-level keywords, some break the hierarchical keywords up and write each level separately. Some maintain legacy IPTC keywords, some mess them up, some silently strip them when updating metadata...

Just to add some extra entertainment if all you want is to work with the same keyword across multiple applications.
-- Mario
IMatch Developer
Forum Administrator  -  Contact & Support - Follow me on 𝕏 - Like on Facebook


There is nothing like a standard to work to. 

And that is nothing like a standard  :)
Have you backed up your photos today?