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e. Capturing Photo-induced Luminescence Images
iv. UV-induced Visible Luminescence (UVL) Images
The workflow shown in Figure 2-30 summarises the corrections proposed as a result of the
discussions in Chapter 1 and also highlights the general transformations to be carried out by
the post-processing software.
od
Camera output Corrected for Corrected Corrected for Corrected for
spatial for camera ambient stray “pigment¬
inhomogeneities response light binder”
of light source (colour interaction
(Flat fielding) calibration)
Figure 2-30. Schematic of the workflow proposed for UV-induced visible luminescence images.
The requirements in order to carry out the image correction procedure are as follows and are
included as a checklist at the end of the image capture workflow (see below):
1) The camera output file, i.e. UV-induced visible luminescence image;
2) The ICC profile (which records all the metadata including the gamma correction applied to
the image. This describes and is created on the conversion from RAW into a standard 16¬
bit TIFF file, see Chapter 3). This profile is contained within the TIFF file and is
automatically retrieved by the post-processing software;
3) An image of a uniform reflective board under the same experimental conditions for flat
fielding;
4) An image of a Spectralon diffuse reflectance grey scale or any number of Spectralon
diffuse reflectance standards as available (included as part of the image to be calibrated
or another image taken with the same camera and lighting conditions);
5) A visible-reflected image (including a Spectralon diffuse reflectance grey scale or any
number of Spectralon diffuse reflectance standards as available) obtained as described in
section i (See above);
6) Image of uniform reflective board under experimental conditions for flat fielding the
visible-reflected image;
7) A UV-reflected image (including a Spectralon diffuse reflectance grey scale or any
number of Spectralon diffuse reflectance standards as available) obtained as described in
section ili (See above);
Version No. 1.0 81 Date : 14/10/2013