We present reliable, serendipitous x-ray detections found in three different deep ACIS imaging fields in two different energy bandpasses. We ran the Chandra X-ray Center's exttt{cell detect} source detection program on a ``soft band'' image (from 0.5 - 2.0 keV) and a ``hard band'' image (from 2.0 - 7.0 keV). The 3 high latitude fields investigated as part of the Chandra Multiwavelength Project (ChaMP) include: MS 1137.5+6625, the second most distant cluster of galaxies in the Einstein Extended Medium Sensitivity Survey (EMSS) at a redshift of 0.78; CL 0848.6+4453, a field containing three galaxy clusters at 0.6 < z < 1.3 (including the highest-redshift non-AGN cluster); and A 0620-00, a short-period black hole x-ray nova (BHXN). The integration times for each field are 120 ks, 190 ks, and 45 ks, respectively. We discuss the optimum set of cell detect parameters and present preliminary analyses such as hardness ratios and log N - log S plots.