Analysis of two‐dimensional electrophoretic protein patterns using a video camera and a computer. I. The resolution power of the video camera

The resolution power of a video camera (Hamamatsu) was investigated under the aspect of employing the camera for the densitometric evaluation of two‐dimensional electrophoretic patterns of proteins. The features of the camera were tested on the illuminated glass pane of a light box and on specimens such as a blank film (X‐ray film), a blank gel (polyacrylamide gel plate) and a bar raster. The digitized values were analysed by a computer. While the hardware permits a half‐tone resolution from 0 (dark) to 255 (bright) grey levels, the values obtained experimentally showed that only 90 (glass pane), 70 (gel) or 60 (film) reproducible grey levels can be resolved, depending on the features of the supporting material of the two‐dimensional electrophoresis pattern. The addressable spatial resolution of the camera comprises 1024 × 1024 pixels. Under experimental conditions, however, only 570 × 700 pixels were resolved. Further investigation in necessary to prove whether the resolution power of a video camera is sufficient for a precise analysis of two‐dimensional protein patterns.