(a) The inclination angle of the beam is 20° to the floor. The film cassette is perpendicular to the central beam of the radiation source. (b) The film cassette is lying on the floor and the subject is standing on the film cassette. The inclination angle of the beam is 45° to the floor. (a) and (b) are reproduced from Reilingh et al. 2010 [5
] [under the Creative Commons Attribution License/public domain]. (c) Participants stood on a radiolucent platform with equal weight on both feet. This platform was flat in the rear part and inclined by 30° in the front part, so that the midfoot and forefoot of participants were planter-flexed. The X-ray beam was oriented down 5° from the horizontal position. (c) is reproduced from Ikoma et al. 2013 [6
] [under the Creative Commons Attribution License/public domain].