Device gamuts are commonly defined for output devices, such as monitors or printers. In this paper, a definition of gamuts of input devices will be examined, considering multispectral cameras as examples. A method appropriate to calculate them as a function of the camera model and the spectral reconstruction algorithm will be proposed. The method will be applied to multispectral camera models with a variable number of channels. The characteristics of the resulting gamuts will be shown and examined as a function of the number of channels. Implications on the minimum number of channels needed will be derived. The method proposed here to characterize input devices can be used in addition to common quality criteria such as color distances like ΔE00, spectral errors, etc. The advantage of the proposed method is the independence of any given spectral data set. This makes it a quality criterion universal for linear (multispectral) cameras and reconstruction algorithms.