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How to digitise slides. Recommendations and working lists for the reproduction of a very special artefact

Decision-making list

How to choose the most appropriate way to digitise a slide collection? The decision-making list

In order to avoid influencing in any way the selection of a digitising tool the following remarks are as impartial as possible. They concern three groups of aspects that are decisive for the choice of activities.

Decision-making list: what could I do – what would I need to do?

1. Can I do the digitisation in-house or would outsourcing be a more convenient way?
Make a list of points to check whether the archive will be able to do the scanning in-house. Parameters could be: budget and funding, time to spend, space for a working area, number of qualified staff, range of experience of staff members, the already existing workload on their shoulders, the aesthetical, historical, financial value and physical quality of the slides to be reproduced, equipment in hardware and software already existing in-house etc.

The alternative: to outsource the activity.
In this case a tender (containing the obligations to be fulfilled, the conditions of the cooperation etc.) would have to be written, the professionalism of the winner tested (very important in order to avoid disappointments later), the company hired, the workflow of the partner (if not specified in the tender) agreed on, the resulting files checked the moment they arrive as to their conformity with the tender’s exigencies (don’t check later as the slides will be back at the archive in storage, the company not willing to redo the scanning etc.).

Both ways have their pros and cons which have to be balanced against each other to make sure to find a decision that will work for the archive. If the archive has enough funding to outsource the work it can be useful to check whether the post production should and can be done in-house. Post production is time consuming and should be done by a specialist in grading (correcting light and colours) to achieve high quality reproduction. On the other hand, in-house post production can be used to check the quality of the outsourced work.

See also the chapter “What to check when the scanning is done by a professional company”.
If you need an example for a tender, please contact A Million Pictures via its website.

2. What will I do with the images once they are digitised?
Scanned slides have a wide range of potential uses. For internal use, you could think of “thumbnails” for the (online) database, the presentation of the collection’s highlights on the website, printed reproductions in publications, the re-use as posters and in a “multimedia show” in exhibitions, the use of digital images for consultation by users in the library. For external use, scans allow exchanges among archives, sales (of reproduction licences) to publishing houses etc. The Swiss media conservation association Memoriav gives three simple questions to help the decision-making process: “Is the goal to simplify access to the collection? To present the holdings on the internet? To prepare an exhibition? To preserve an ensemble of photographs?” (Aeby et.al. 2017, p. 35). The answer determines the technical parameter which will be applied.

To be useful for these activities the reproductions need different qualities in resolution and colour. The internet requires low resolution files with a small range of colours, the printing of a poster for an exhibition demands high resolution scans with a broad range of colour nuances.

Slides can also be digitised to “just preserve” them: from that moment on their digital reproduction will be used for many archive activities. This significantly reduces the need to get them out of the vaults. In this case it is necessary to decide how a slide should be digitised: just the image, the whole item including inscriptions on its front and its back or also the edges of the frame as they can contain historical information. A scan would be enough for the first two options, the third one requires photographic reproduction.

Slides are often part of collections that contain items of another nature (e.g. lanterns and accessories, documentation) and in different physical conditions (e.g. voluminous, opaque). The question is whether they will be included in the initial digitisation (together with the slides) or a later apart, or even in another project. Papers and slides can be scanned, pronounced three-dimensional objects will need to be photographed. Flatbed scanners are specially made to copy paper, photo cameras are efficient when it comes to mimicking three-dimensionality.

These examples show: it should be made clear what is needed as the intentions have to play an important role in the decision on the reproduction method and the needed quality.

3. Do I need to organise mass digitisation or can I concentrate on small-scale reproduction?
Some collections are small, others contain thousands and thousands of slides. This generally requires different approaches. While small collections can be done within a limited amount of time, big ones need a different strategy.

The reproduction of a small collection often needs individualised defaults as parameters can change from slide to slide. As the slide taxonomy established by the Salamanca working group of A Million Pictures shows they can be heterogeneous in form, format, colour, working function (mechanism), physical condition etc. Such a “small scale digitisation” can be done by scanner and still-camera as most slides will need an individual treatment.

It is important to know whether the big collection can be divided into smaller portions. This is necessary in order to decide how the sub-sections of a collection might be dealt with according to the above-mentioned factors (see point 1. Can I do the digitisation in-house?) that are the limits for the digitising activity. If a certain number of slides are of the same size, are made the same way (painted, printed, photographed, hand-coloured), are flat and may even come from the same producer, then standardised settings are useful. Mass digitisation should be considered except for particular collection parts characterised by special qualities that need individual handling and settings. What is more practical here – scanning and / or photographing – is a question to be answered when taking into consideration point 1 (“What will I do with the images once they are digitised?”) and point 2 (“What shall I do with the images once they are digitised?”).

4. The budget
A final comment in addition to the first three points: what can be done, and how it can be done, is often limited by the budget. A precise – and relatively detailed – evaluation of necessary financial resources speaks for itself. Before starting the project, it is important to asses the long-term storage needs of the digital asset. These should be budgeted for with the other activities. While a digitising project can generally be precisely calculated given its limited temporal scope, but it is more difficult to project the quantity and number of activities, the long-term costs to conserve the digital reproductions. To avoid running into difficulties during or after the project the Swiss Memoriav report on digitising photographs insists that: “[…] storage space is not for free, on the contrary: storage space suited for preservation causes recurrent costs which can be considerable with huge data packages. […] Therefore it is recommended to check the question of digital storage and to assure sufficient financial support before starting the project to digitise […].” (Aeby et.al. 2017, p. 45)

5. Documenting the entire process
During the decision-making process it is advisable to take notes: “All decisions associated with planning a digital project must be documented. Keeping a record of the institutional and technical evaluations will help future staff members and others understand why certain decisions were made. Making and revising these decisions should be a group effort, because various degrees of expertise are required at various times.” (Colet 2000)

Recommendations by the author:
Before continuing with the “Scanning slides” or “Photographing slides” sections it is advisable to first read the chapter titled “Technical processes” so as to take into account the technical disposition of the aforementioned devices, as both work with the same digital technology.