Wednesday 3 May 2017

Webinar: preparing to digitise your archives

Long time no blog! I've been on maternity leave, and am planning to write some reflections on that and returning to work soon. But, in the meantime, here's my write up of a webinar I took part in last week from The National Archives. As with the previous webinar I've taken part in, on forward planning, this was a great opportunity to learn more about a topic in a free and easy format, as it only took an hour of my time at work and there was no need to even leave the building!

It was clearly structured and covered the basics of planning a digitisation project. This is my summary of the contents:

Scope your project
  • Spent time deciding what to include and exclude in your project. Digitisation is costly so avoid creating extra work by trying to digitise too much. Be focussed!
  • Start with a small pilot, digitise a small sample and run it through all of the digitisation processes.
  • Consider possible outputs. Tiff files are the most sensible format to capture for the master copy, with 300PPI for most paper originals and 400-600PPI for photographs. PDF is not recommended.
In-house or outsourced?
This decision depends on the size of the project, type, budget and internal capacities. The pros and cons are:
Outsourcing
Pros: Can be cheaper, technical knowledge isn't needed, less stress for staff, saves time  
Cons: Less control over project, relocation of collection/providing access to the material, fragile or sensitive material, restrictions on rescoping the project once it is underway.
In-house
Pros: More control, staff skill development, may save money in the long run, keeps collections in one place
Cons: Lack of in-house skills, big investment in equipment needed, lack of suitable infrastructure, no in-house experience

If considering outsourcing: shop around, get quotes and look at company's existing work. Visit their site and check their set up. Ask for samples early on in the project and have regular project catch ups. Make sure you have a contract.

Document preparation
Preservation/conservation: Assess condition of the collection and whether work by a conservator is needed in order to digitise without damaging the originals. Remove all metal pins, clips etc. Digitisation can take place through Melinex sleeves. How are you going to digitise books safely - unbind the volume, use a camera rather than a scanner etc?

Consider capture and post-processing equipment
There are pros and cons to using cameras and scanners.
Document preservation: a camera provides more alternatives to capturing the image without causing damage
Image quality: cameras tend to produce better results
Price: bear in mind that equipment needs to be kept up-to-date (this should be factored into the cost of outsourcing). Depending on the size of the project, renting equipment may work out cheaper.
Useability: scanners tend to be more straightforward to use with fewer settings. Cameras require colour calibration and that the lens be kept clean.
Versatility: scanners work well with flat materials, but aren't suitable for digitising books. Cameras tend to offer more versatility.

Post processing
Images are usually captured in RAW format then need to be processed. RAW files are very large, so this needs to be considered when assessing file storage needs. Obviously the file format must be compatibile with the image processing and storage software being used.

Metadata and storage
Technical metadata is included at the capture stage, for instance camera settings, focal length, exposure. It may be embedded within the image and then shared in a spreadsheet.
Descriptive metadata is the description of what the item is, such as names, dates and places so that the digitised image is discoverable. It can be captured by OCR (although this has severe limitations) or manually (time consuming and expensive).
Storage ensure you have the the basics, such as a server large enough to store the files and a means of backing them up.

What I've learnt and will take forward:
Visit other archives/Special Collections to learn from their experiences.
Keep it as simple as possible and only capture what is relevant. 
Know what the outcomes of the project are before commencing image capture. 
Never destroy the original after digitisation, unless they are acetate negatives.






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