less than 0.1, so this cut simply rejected obvious background galaxies, and also served to eliminate partially resolved pairs of objects.

Target Selection: Optical Colors
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In addition to selecting on size and shape, we instituted color cuts to increase our efficiency. Globular clusters are old, single-age stellar populations that have optical flux predominantly produced by stars from the main sequence turnoff to the red giant branch. The integrated colors of these stellar populations are produced by combinations of stars with types F through K (and maybe also A-type giants for GCs with blue horizontal branches). The result is that the spectral energy distribution of a GC is broader than that for any individual star. Hence, with a long enough wavelength baseline and sufficiently accurate photometry, we should be able to distinguish GCs from stars using colors alone.

Figure \[figure:colorselect\] shows a ([$U$–$V$]{})–([$V$–$I$]{}) color-color diagram—the combination of colors that offers the widest wavelength baseline for our data. The black dots are objects in our CTR field with $14<V<20.5$. The dense concentration of points outline the $UVI$ stellar locus. As in Figure \[figure:sharpFWHM\], all confirmed stars and GCs are overplotted as blue and red plus symbols, respectively. Although the division is 