Prevent custom plugin metadata fields from being copied when creating virtual copy

[mppowell]

I am new the writing lightroom plugins, and am trying to make a plugin that generates a unique identifier for images to be help with tracking variants of images in my sales workflow. The plugin needs to treat each virtual copy of the same image seperately so that the unique id is not duplicated anywhere in the catalog. I am trying to use a custom metadata field for the unique identifier and have been setting it using the "setPropertyForPlugin" method. However, I notice that the metadata field is copied over to a virtual copy when the original photo has the metadata field populated. Is there a way to prevent a metadata field from being duplicated in a virtual copy?

[johnrellis · Accepted solution]

As discussed in your other post, fields set with catalog:setPropertyForPlugin() are per-catalog, not per-photo; for per-photo fields, use photo:setPropertyForPlugin().  

Unfortunately, the per-photo custom fields get copied into the virtual copy when it is created. There's no way to stop that.