SummaryDevelopments in image capture technology allow developers of multimedia applications to incorporate source material of varying physical characteristics. However the multimedia developer drawing up a specification for a capture system is faced with a bewildering choice of equipment for which there is little comparative information on the relationship between equipment specification and captured image quality. This report provides guidelines for decisions on the choice of appropriate capture pathways within the context of higher education.
This project evaluated two equipment scenarios, differentiated on cost for hardware with associated software, and PhotoCD origination for capturing images for inclusion in multimedia applications. Classes of image relevant to teaching in a range of university departments were identified. Original source material was captured using different hard copy and electronic media, digitised and stored on an optical disc. The different versions of each image were ranked against each other and qualitatively scored for spatial resolution (sharpness), colour faithfulness and contrast ratio. Standard charts used in broadcasting to test spatial resolution, contrast ratio and grey scale were used to provide quantitative assessment. The effect of compression and image manipulation are not considered in this report which is part of the ongoing research programme.
On the basis of the results obtained, guidelines were drawn up on systems specification and image capture for developers of multimedia application in higher education. The guidelines recognised that photographic, video and computing skills, and high quality source materials are as important as having suitable hardware if high quality images are to be obtained. Overall the results indicated that the best digitised image on the basis of the three established quality criteria was obtained from a combination of a 35mm slide or negative plus digitisation via PhotoCD. Of the other options there was no clear winner between video rostrum cameras and scanners. The use of the still video camera and single frames from a video tape failed to produce acceptable results. Whilst PhotoCD produced the best result for three dimensional subjects and flat art, for photomicrography the use of a rostrum camera offered the distinct advantage of being able to view the displayed image before capture.