Man and Cameraman: Digitisation
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Transcript of Man and Cameraman: Digitisation

Ed Fay
Institute of Conservation Photographic Materials Group
22 September 2011
Man and Cameraman:Digitisation

Handling• Fragility of glass• Curling negatives

Equipment – pre-existing
• Hasselblad Flextight X5• High-end, virtual drum scanner
• Epson V750• Low/mid-range flatbed

Equipment - required
• No bending of the prints or negatives – (no drum or virtual drum scanner)
• Ability to hold negatives flat for imaging
• Overhead, non-contact shooting of the albums – camera with scanning back
http://www.largeformatphotography.info/scan-comparison/

Equipment – flatbed scanner
• Creo iQsmart3• High-end, archival
quality flatbed• 5,500 dpi optical
resolution
Used in archival digitisation projects:• Freeze Frame (JISC/Cambridge)• John Thomson (Wellcome)• Holtermann Collection (State
Library, New South Wales)

Equipment – planetary scanner• Betterlight Super 6K-HS• Digital scanning back• 6000 x 8000 pixel CCD• 48 megapixel output

Suppliers
• Creo iQsmart3◦ Identified three potential suppliers◦ Used two simultaneously to run 35mm and
nitrate in parallel
• Planetary scanner (Betterlight/Hasselblad)◦ Identified several (including all with Creo)◦ Used existing supplier with high quality outputs

Digitisation approach
• 3 levels of quality:◦ Archival – no post-processing◦ Master – cropped, levels adjusted◦ Access – lower quality for web
• Archival & Master kept for negatives• Master only kept for prints and albums

Digitisation - Archival• “Condition of the source material is exceptionally rare or
fragile. Digitisation is carried out in part to contribute to the preservation of the original by reducing handling and producing high quality surrogates that will themselves serve as preservation masters.
• Archival files will not undergo any post-processing (e.g. images: deskew/colour balance; audio: noise-reduction; etc.). The purpose will be to produce an “authentic” copy of the original, regardless of quality. For example, an image will retain its original contrast, colour-balance and physical markings.
• A master version will be produced from the archival version for access. Both versions will be retained.”

Digitisation - Master• “Condition of the source material is not exceptional.
Digitisation is carried out primarily for access. The digital surrogates will be of sufficient quality to meet access requirements for the foreseeable future, but may themselves have no preservation expectations placed upon them.
• Master files may undergo post-processing (e.g. images: deskew/colour-balancing; audio: noise reduction; etc.). The purpose will be to produce a “best” copy rather than an “authentic” copy from the original. For example, the light/colour balance of an image may be adjusted to produce a visible/best image and to remove physical defects.
• These standards should apply to the majority of collections and projects.”

Digitisation - Access• “Standards which apply to the online access or publically
available versions of digital surrogates. These versions are non-permanent from a storage/retention perspective and will usually be derived from the master versions according to requirement.”

Technical specification35mm Nitrate Prints Albums
Archival TIFF 4000PPI
48bit RGB Adobe 1998
TIFF 1200PPI
48bit RGB Adobe 1998
[not stored] [not stored]
Master TIFF 4000PPI
24bit RGB Adobe 1998
TIFF 1200PPI
24bit RGB Adobe 1998
TIFF 1200PPI
24bit RGB Adobe 1998
TIFF 600PPI
24bit RGB Adobe 1998
Access JPEG 72PPI
24bit RGB sRGB
JPEG 72PPI
24bit RGB sRGB
JPEG 72PPI
24bit RGB sRGB
JPEG 72PPI
24bit RGB sRGB

Colour profiles
• Adobe RGB 1998 for archival/master images
• sRGB for access images
• Colour-balanced workflow◦ scanner (input device)◦ embedded (working space)◦ monitor (output device)
• Aim: Authenticity to original

Post-processing
• Crop◦ Inside physical edge
• Histogram levels◦ Contrast, tonal range

25% 50% 75% 100%

Integrity management
• Directory structure according to format and digitisation category:
//[server]/shaw/35mm/archival/
• File naming according to hierarchical catalogue identifier and format:
SHAWPHOTOGRAPHS_3_257_1_2.tif
• Conformance to technical specification checked automatically

Digital preservation
• LSE Digital Library



Questions
?

Image creditsColorspace (CC-BY) Cpesacreta
http://en.wikipedia.org/wiki/File:Colorspace.png
[Various Shaw negatives] © LSE Library(reproduced with permission of Society of Authors)
[Various imaging processes] © Max Communications(used with permission)
All other images(CC-BY-NC-SA) LSE Library