3.5.1.2  Digital Object ID vs. Image ID

The two terms sound confusing.  Here's the difference: the Image ID number is the device that ties the Image record to its parent, the Text record.  It's exactly the same kind of device as the Manuscript ID number, the Part ID number, the Text ID number; we humans pay no attention to these numbers; they are under the strict hegemony of the computer with the sole exception of their function in the Reassigning process.  Please go look under Reassigning to read all about it.

On the other hand, the Digital Object ID number is the designator for the image itself.  It may become part of the URL for that one image.  You will have decided upon formation of the URL when you determined the default Settings, whether you chose complete autogeneration by the computer with its various components, or whether you chose to hand-insert your own institution's ID into the Digital Object field on the Image form, and then to depend upon autogeneration for the rest of the URL's formation.  This and the explanation for the button on this form, URL Generation Settings, are more fully laid out in the relevant section in Settings.

Again, for the sake of completeness at this point, we repeat that some institutions will use the Capture ID instead of the Digital Object ID in the URL.  Functionally, these two are the same for purposes of generating the individual image's URL:  each is the unique identifier for the one image.  The difference is that DigitalOjectID's properties refuse duplication, while CaptureID's properties allow it.  One guess as to which is the safer choice.