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Two-dimensional planar imaging and one-dimensional, spectrally-resolved line-imaging of laser-induced fluorescence from CO and UHC are performed to help identify the sources of these emissions in a light-duty diesel engine operating in a partially-premixed compression ignition combustion regime. Cycle-averaged measurements are made in the clearance volume above the piston crown at a 3 bar IMEP, 1500 rpm baseline operating condition. Sweeps of injection timing, load, and O2 concentration are performed to examine the impact of these parameters on the in-cylinder spatial distributions of CO and UHC. At the baseline operating condition, the main contributions to UHC from the clearance volume stem from regions near the cylinder centerline and near the cylinder wall, where UHC likely emanates from the top ring-land crevice. Broadly distributed CO within the squish volume dominates over CO observed near the cylinder centerline.