Consider a journal series published by a learned society, for example Antiquity. This series might be catalogued by the HER on three levels:
Cataloguing at the collection level provides a useful first step. Such a source record will help HER managers to record details about the collection, the originator, the materials/items included and any copyright or other issues to be considered.
However, as a general rule of thumb, it is probably most practical for HERs to catalogue their collections at the unit level. It is useful for each book, box of photographs or set of papers to have a single source record which contains information about the place where that unit is stored and other details that help to manage the HER's collections.
Cataloguing at the item level may be appropriate in some circumstances. For example, HER managers may decide to create source records for particularly useful articles in a journal without recording all the other articles at this level. Cataloguing at item level can be a significant overhead and HER managers might prefer to number the items uniquely within a unit (for example the photographs in a box) and create a single source record containing a list of the items and their identifying numbers.
Consider, for example, a set of photographs from a single roll of film taken by J K S St Joseph during a flight on 3rd July 1979. Each image on the roll of film will have a unique negative number and the film and negative number may be used to identify each photographic print from the film. HER managers might decide to create two source records. One source record will be for the roll of film, containing details of its storage location and the type and format of the film. A separate source record might be created for the set of prints, giving details of the print numbers and their storage location, which will normally be different to that of the film for collections management reasons. At a later date, separate source records might be created for each individual print, perhaps if the prints were scanned or if the subject content of the photographs were to be described in detail.
As described in section C.8.1 many datasets are now available online and are able to be downloaded into the HER if necessary.