Camera characterisation

In order to measure an object in terms of device independent colom from a digital camera, there is a need to correlate the camera RGB signals and CIE XTZ values. This is known as camera characterisation. 

Alternatively, Spectral Based Camera Characterisation can be used. This can be divided into two measurement of the spectral sensitivities of the camera and recovery of the spectral reflectances. Both will be introduced later. 

Spectral-based camera characterisation can be further divided into two methods ... 

There are three methods for colorimetrically characterising a camera, namely ... 

HONG G, LUO, M R and RHODES, p (2001) A Study of digital camera colorimetric characterisation based on polynomial modehng. Color Research and Application, 26, (1), 76-84. 

ISO 17321 (1999a) WD4 Graphic technology and photography Colour characterisation of digital still cameras (DSCs) using colour targets and spectral illumination. 

In preliminary tests performed on the X-ray camera a subarray of 5x5 strips was used to obtain a 25 pixel detector each strip coupled to a hybrid charge sensitive preamplifier (CSP), model CS 507, produced by Clear Pulse (Tokyo) in a modified version with external input FET and a resistive feedback loop CSP is characterised by an equivalent noise (r.m.s.) of about 1 keV. Pulses from CSP... 

With slit collimation, higher resolution may be obtained with much less loss of intensity. Such cameras are, for example, of the Rigaku-Denki and Kratky type, the latter employing an ingenious U-bar collimating system which permits resolution up to several thousand angstroms. While slit cameras may not readily be used to characterise degrees of partial orientation, a compromise is possible with cameras of... 

Because of these results a video microscopy check on the homogeneity of the gas bubbles in the liquid mixture was performed. For this test the ingredients of a standard foam formulation were mixed and immediately poured onto a polished metal plate. The creaming of the foam was then filmed by a video camera with a lOx magnification. Thirty and 150 seconds after the stirring commenced, a video printout was made and the number of formed gas bubbles as well as their size homogeneity was characterised (see Figure 2.12). This procedure is referred to as the video test. 

Hong G., Luo M. R., Rhodes P. A. (2001), A Study of Digital Camera Colorimetric Characterisation Based on Polynomial Modelling, Colour Imaging Institute, University of Derby, UK. 

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