A talk delivered by David Howell at the Anybook Oxford Libraries Conference 2015 - Adapting for the Future: Developing Our Professions and Services, 21st July 2015
Using Collections Differently: Analysis and Secialist Imaging Techniques
1. Using Collections Differently: Analysis and
Specialist Imaging Techniques
David Howell
HEAD OF CONSERVATION RESEARCH
The fields of digital imaging and
spectroscopic analysis are increasingly
converging into a developing specialization
of Analytical Imaging. In this seminar I will
show examples of the use of Reflectance
Tomography Imaging and hyperspectral
imaging
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6. Dispersive IR
instruments are introduced in
1940’s.
Double-beam
instruments are mostly used
than Single beam instrument.
In dispersive IR
sequential scanning of wave
numbers of light takes place.
Dispersive IR
Instrument
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9. To separate IR light, a grating is used.
Grating
Light source
Detector
Sample
Slit
To select the specified IR light,
A slit is used.
Fixed CCM
B.S.
Moving CCM
IR Light source
Sample
Detector
An interferogram is first made
by the interferometer using IR
light.
The interferogram is calculated and transformed
into a spectrum using a Fourier Transform (FT).
10. This means that as the interferogram is measured, all
frequencies are being measured simultaneously. Thus, the
use of the interferometer results in extremely fast
measurements.
Because the analyst requires a frequency spectrum (a
plot of the intensity at each individual frequency) in order
to make an identification, the measured interferogram
signal can not be interpreted directly.
A means of “decoding” the individual frequencies is
required. This can be accomplished via a well-known
mathematical technique called the Fourier transformation.
This transformation is performed by the computer which
then presents the user with the desired spectral
information for analysis.
13. 1304/09/2015
This colloquium aims to convene scholars from a
wide-ranging selection of fields in order to explore
how knowledge is created through the act of
interpretation of ancient documents.
Each session will put into dialogue the work and
methods, both digital and more traditional, of
ancient documents scholars with findings from the
cognitive sciences around the processes involved
in the act of interpretation of ancient documents.
23. The 150 years of Colour Photography
23
The first colour
photograph made
by the three-color
method
suggested
by James Clerk
Maxwell in 1855,
taken in 1861 by
Thomas Sutton.
The subject is a
coloured ribbon,
usually described
as a tartan ribbon.
Kodachrome 1935
Ektachrome 1946
Polaroid 1963
2004 Last slide projector
2005 Production of Agfa
consumer films ends
2009 microfilming
stops at Bodleian
1927 microfilm widely
used in libraries
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24. What age are we in digitisation?
24
1974 production of
first digital camera
1984 first commercial
digital camera
2011 Stanford to develop
3.2 gigapixel camera
3D topography
More accurate colour information
Revealing hidden texts
Revealing materiality
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25. COMMUNICATION, LANGUAGE AND POWER
IN THE ACHAEMENID EMPIRE
The correspondence of the satrap Arshama, prince of the royal
house and satrap (governor) of Egypt in the fifth century BC.
The parchment letters of the Persian prince Arshama to
Nakhthor, the steward of his estates in Egypt, are rare
survivors from the ancient Achaemenid empire. These
fascinating documents offer a vivid snapshot of linguistic,
social, economic, cultural, organisational and political
aspects of the Achaemenid empire as lived by a
member of the elite and his entourage.
Arshama’s letters to Nakhthor, two leather bags and clay
sealings, entered the Bodleian Library in 1944.
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30. Hyperspectral Imaging using
Headwall Equipment
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A stamp on the Gettysburg
Address that cannot be
seen visibly but can when
looked at within the VNIR
and SWIR spectral range.
56. Current challenges and opportunities
• Files are huge;
– Where to store them and
how to back up?
– How to minimise and
automate data processing?
– Data processing is complex
• Application to Microsoft
Azure
• Fell funded DPhil starting in
September
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57. Thank you for your attention.
Questions?
(but only easy ones please!)
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Editor's Notes
Recently there was a two day colloquium on ‘reading texts’. Some of this confirmed the limitations of what could be ‘seen’ with the eye only and that research into further visualisation techniques would be useful.
