Digitizing an Analog Radiography Teaching File Under Time Constraint: Trade-Offs in Efficiency and Image Quality

Abstract

We digitized the radiography teaching file at Black Lion Hospital (Addis Ababa, Ethiopia) during a recent trip, using a standard digital camera and a fluorescent light box. Our goal was to photograph every radiograph in the existing library while optimizing the final image size to the maximum resolution of a high quality tablet computer, preserving the contrast resolution of the radiographs, and minimizing total library file size. A secondary important goal was to minimize the cost and time required to take and process the images. Three workers were able to efficiently remove the radiographs from their storage folders, hang them on the light box, operate the camera, catalog the image, and repack the radiographs back to the storage folder. Zoom, focal length, and film speed were fixed, while aperture and shutter speed were manually adjusted for each image, allowing for efficiency and flexibility in image acquisition. Keeping zoom and focal length fixed, which kept the view box at the same relative position in all of the images acquired during a single photography session, allowed unused space to be batch-cropped, saving considerable time in post-processing, at the expense of final image resolution. We present an analysis of the trade-offs in workflow efficiency and final image quality, and demonstrate that a few people with minimal equipment can efficiently digitize a teaching file library.

A Low-Cost High-Quality Mobile X-ray Film Digitiser with Storage Facilities

“…Digitisation of X-ray films reduces need for storage space and facilitates remote diagnosis, personal collections, teaching and publication [1][2][3][4]. There are many commercial units available costing between USD10-20,000 excluding maintenance, servicing, repairs, software and training costs [1,5].…”

“…There are many commercial units available costing between USD10-20,000 excluding maintenance, servicing, repairs, software and training costs [1,5]. Alternatively, satisfactory results may be obtained by expertly photographing an X-ray, mounted on a viewing box, using a hand-held digital camera [1,4]. However, when using a wallmounted viewing box, the image may be marred by reflections from sources of bright light, especially windows.…”