4.5 Colour control True-to-life colour reproduction is an important factor in wound management photography, and it can be useful at the capture stage to include a calibrated colour chart or neutral grey card in the frame (where practicable), or at the beginning of a series of images from which to set the white balance. Starting with an accurate white balance ensures the colours captured are true. It also provides a consistent reference point for minor adjustments to the photograph at the editing stage. At the editing stage, monitor calibration is the first step to controlling colour in a digital workflow. Monitor calibration serves two main purposes; 1.
it enables photographers to edit images with confidence because the colours displayed on the screen are an accurate reflection of those captured on the digital image file. 2. it can help to ensure that the colours seen on screen closely match output (if prints are to be produced). There are a number of ways that this can be achieved and monitors and printers should be calibrated regularly to ensure consistency.
4.6 Measurement scales The L-shaped ABFO#2 scale is ideal for use in wound photography (providing the wound presents no significant risk of infection) and in particular, for photography of suspected non-accidental injuries as it was designed specifically for legal purposes, providing crucial measurements in both horizontal and vertical directions. The scale should be held in place on the same plane as the wound, with the wound being photographed from a 90° angle. It should be held in place by the corner, with care being taken to ensure the circular marking is visible, to demonstrate that correct perspective has been achieved (Figure 13 and 14).
Care must be taken not to apply excessive amounts of pressure to the area with the scale, as this may distort the appearance of the wound. The L-shaped ABFO#2 scale is reusable and as such, must be disinfected according to local protocol, after each episode of patient use. Figure 13. Correct positioning resulting in no distortion (reproduced by permission of Sam Evans, Cardiff University). page 14