The present invention relates to the production of instantaneous or non-instantaneous multi-band images, to be transformed into multi- or hyperspectral images, comprising light collecting means (11), an
image sensor (12) with at least one two dimensional
sensor array (121), and an instantaneous colour separating means (123), positioned before the
image sensor array (121) in the
optical path (OP) of the arrangement (1), and first uniform spectral filters (13) in the
optical path (OP), with the purpose of restricting imaging to certain parts of the
electromagnetic spectrum. The present invention specifically teaches that a filter unit (FU) comprising colour or spectral filter mosaics and / or uniform colour or spectral filters mounted on filter wheels (114) or displayed by transmissive displays (115), is either permanently or interchangeably positioned before the colour separating means (123) in the
optical path (OP) in, or close to, converged light (B). Each colour or spectral filter mosaic consists of a multitude of homogeneous filtering regions. The transmission curves (TC) of the filtering regions of a colour or spectral filter mosaic can be partly overlapping, in addition to overlap between these transmission curves and those belonging to the filtering regions of the colour separating means (123). The transmission curves (TC) of the colour or spectral filter mosaics and the colour separating means (123) are suitably spread out in the intervals of a spectrum to be studied. The combination of the colour separating means (123) and the spectral or colour or spectral filter mosaics produces different sets of linearly independent transmission curves (TC). The multiple-filter image captured by the
image sensor (12) is demosaicked by identifying and segmenting the image regions that are affected by the regions of the multiple filter mosaic, and after an optional interpolation step, a multi-band image is obtained. The resulting multi-band image is transformed into a multi- or hyperspectral image.