Abstract
Hall and Lloyd (1981) describe the advantages of the semiconductor backscattered-electron (BE) detector used in a scanning electron microscope (SEM) at a normal high vacuum, and they compare that technique with the scintillator backscattered-electron/low-vacuum technique described by us (Robinson and Nickel, 1979). As the former technique is relatively common, we have been able to see it in operation on various SEMs whereas Hall and Lloyd apparently had not had the opportunity to evaluate the low-vacuum technique at first hand before publishing their paper. We would like, briefly, to answer some of the points made by Hall and Lloyd (1981), and especially to disagree with one of their main conclusions, that “carbon-coating is found to be the best method of preventing the specimen from charging” during SEM examination of geological samples.
