Process: Photographic Digitisation

For anyone who would like to know more about the technicalities of what the photographic digitisation process of archives at UCL involves, read on...

1. Firstly the digital curation team would talk with a conservator about the condition of the item. We would find out if it is suitable for digitisation, if it needs any conservation work to be done on it before digitisation and whether it has any specific needs that need to be met during digitisation, for example it must be kept at a certain temperature and can only be removed for digitisation for so long.
2. We would then discuss with the person who requested the digitisation what the end product is going to be, for example in which format do they want the images (TIFF, JP2, PDF are the formats I tend to use), how do they want the images to look and where are they going to end up.
3. Once the item’s condition has been assessed and it is agreed that it is suitable for digitisation, using the catalogue, hand list or other finding aid, we would use the item reference number to find its location in the stores. Once at the location, we would write out an archive request slip, detailing the date, my name and the reference number of the item to be removed.
4. Now, I would unpack the item on a table, handling it carefully, looking at it and assessing its needs during the digitisation process. I would find out the optimum way to image the item, for example with or without foam supports, under glass or not.
5. Once I have established how I am going to image the item, I would set up the camera on the copy stand, turning on the lights so that they have time to warm up. The lights should be at 45° or lower to minimise flare in the images. I choose the best lens for the item, for example selecting a macro lens if the item is particularly small. Attaching the camera to the copy stand, the camera should be level with it, so I use a spirit level to check this. I adjust the height of the camera so that the item fits in the image frame.
6. Handling the item as little as possible, I would then image the item. I take the first image of the item with the X-Rite ColorChecker Passport in the same frame at several different shutter speeds and f-stops, so that I can assess which settings lead to the correct exposure. In order to check this, I open the image in Adobe Camera Raw and check the value of the white square on the ColorChecker Passport, which should be 235. I choose the settings which lead to an exposure closest to 235, and I capture the images.
7. Once I have captured all of the images, I would open them in Adobe Camera Raw, generally using 600PPI. Here, I would select all images and apply the same settings to each, again checking the white balance is at 235, adjusting if necessary, and checking that the black square is set at about 50. Using the white balance tool, I select one of the grey squares in the middle of the ColorChecker Passport in order to neutralise the image, bringing the Red, Green and Blue numbers closer together.
8. Depending on the form of the item being imaged, I would process it in a particular way in Adobe Camera Raw. For example, if it is a book or pamphlet with multiple pages, I would straighten each page with the straighten tool and crop all images to the same dimensions.
9. Finally, I would save the images. I would save the images according to the standard used by the team, generally incorporating the item reference number. I would save the RAW files as TIFF for the preservation files, to be stored on the Digital Curation Drobo hard drive. These masters can then be converted using Photoshop or software such as IrfanView into whichever format required.
10. I would return the item to its location in the stores at the end of each day until imaging is complete, so that it is kept in its preservation conditions as much as possible. If the digitisation will last more than one day, I make a note of the settings used on the camera and in Adobe Camera Raw so that I can retain consistency over time.