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Many events relate to an image. Be that the capturing of an image, the upload of an image, the processing of an image, or even to the fact that the image isn't there. That is, the events refer to a specific image. That also means that a successfully captured, uploaded and processed image leaves a trail of events describing its path. This association between events and a specific image is the event chain, which is identified by the id of the image that created the chain. Each event that forms part of a chain will display that id under the event type if expanded:
You can click on this event chain to set the filter to display only events in this chain, making it easier to trace the path of a certain image through the system. You can also enter an image id into the event chain filter field manually, but this is generally not recommended.
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