With staring infrared sensors becoming more predominant, an increasing number of system Modulation Transfer Functions (MTFs) are being extracted from undersampled imagery. Contamination of the MTF measurement caused by aliasing must be avoided by using a superresolution technique. We compare differences in the utility of two of these techniques: the tilted edge technique, which is commonly used, and the tilted slit technique, which is not. While the tilted edge MTF measurement is taken for granted, the use of the tilted slit is both innovative and instructive. The differences between the two techniques are examined to determine their ability to successfully extract the MTF from an undersampled image without noise, with white noise, with fixed pattern noise, and with various angles of tilt. Ease of implementation is also considered. All things considered, the tilted edge technique is more easily accomplished and gives superior results. The tilted slit technique, however, gives valuable insight into the nature of aliasing in the real world. It is shown to be an excellent tool by which the difficult concept of aliasing may be easily illustrated.