A device is shown for measuring the angle of inclination of a radiographic imaging cassette. The device has a digital inclinometer, such as a MEMS accelerometer, configured to measure the angle of inclination of the cassette with respect to gravity. The device may be portable, including a display coupled to the inclinometer for indicating the angle of inclination of the cassette. The display may be a digital readout, or an analog meter having radio-opaque gradations such that the angle of inclination is recorded on an image processed from the imaging cassette. Alternatively, the digital inclinometer may be integrated into the imaging cassette, and be configured such that readings from the digital inclinometer may be uploaded to a digitizer via an RF transmitter or other transmission means.