Analysis methods: Fig. 5.4 shows a radiography taken by the JSGI phantom. Uneven acryl parts are used to evaluate contrast resolution of an image intensity. Square wave μ chart is used to evaluate sharpness. Using four circles in the corner, the minimum and maximum values of dynamic range can be determined. Dynamic range is the ratio between the largest and smallest values of a changeable quality (Fig. 5.5). Contrast transfer function (CTF) is to be calculated using the μ chart data, which modulate the amplitudes and phases of the electron diffraction pattern (Fig. 5.6). The standard deviation (σ) can be used to quantify noise directly, which is the relationship in quantum-limited imaging, where noise (σ) is proportional to the square root of the dose (Fig. 5.7). The calculated values enable tracking of the age of deterioration of the equipment. However, it is worth mentioning that the radiographies used for the analysis went through a number of image processing methods, and the calculated values should be treated as reference.