Remote sensing of the atmosphere and the surface of the earth is performed by the Imager and Sounder instruments onboard the GOES (Geostationary Operational Environmental Satellite) Satellites. By employing large PV Hg1CdTe focal plane array (FPA) detectors, instruments like the Advanced Baseline Imager (ABI) and Advanced Baseline Sounder (ABS) will provide improved update times, resolution, and sensitivity. However, uniformity in the pixel geometry across the array must first be demonstrated in order to maintain the accuracy of weather products at each spot on the ground. This uniformity is particularly important in weather products involving radiance subtractions and ratios from multiple spectral bands employing different detectors. Measurement ofthe spatial response associated with a pixel is important in determining both ground resolution and the effect ofradiance from outside the pixel field-of-view. Therefore, a high precision test set-up has been developed at Lincoln Laboratory to measure both the modulation transfer function (MTF) associated with each pixel in the array and the cross-talk from pixel to pixel. Details of the test set up and initial results of the testing will be discussed.