Imaging: Segregation based on colour

Digital fundus cameras are found throughout optometry practices and retinal photography is accepted as a standard part of any eye examination. Multi-wavelength incident light illuminates the retina and the reflected image is captured on a sensor in digital form for transfer, storage or further enhancement as required. Image quality can be influenced prior to capture by changing the light input, for example by adjusting the flash intensity or the aperture size, and this is important to maintain image quality across the wide range of eyes being imaged. After capture, images can be enhanced by changing the colour channels or by removing colour completely as required (figure 1a-c).