Emission theory predicts that high brightness cold field emitters can enhance imaging in the electron microscope. This (neglecting chromatic aberration) is because of the large (coherent) probe current available from a high brightness source and is based on theoretically determined values of reduced brightnesses up to 10(14) A/(m(2) sr V). However, in their analysis, the authors find that statistical Coulomb interactions limit the reduced brightness of even atomically sharp cold field emitters to 10(11) A/(m(2) sr V) and regular tungsten cold field emitters to around 2 X 10(8) A/(m(2) sr V). The authors also find that for tip radii in the range from 5 nm to 1 mu m, cold field emitters do not outperform larger Schottky (thermal field) emitters. Although this is applied to only one geometry, they expect that similar results will occur for most other cases due to a distinct difference in the behavior of different beam regimes. (c) 2010 American Vacuum Society. [DOI: 10.1116/1.3502642]