ISO 8478:2017 specifies a method for measuring the spectral transmittance of camera lenses. It describes particular conditions for measuring the axial spectral transmittance, over a wavelength range from 350 nm to 700 nm, of camera lenses which are intended to be used mainly for taking pictures of very distant objects.

If the spectral transmittance values are used exclusively for the calculation of the ISO colour contribution index (see ISO 6728) throughout ISO 8478:2017, the wavelength range reads 370 nm to 680 nm.

ISO 8478:2017 is also applicable to mirror lenses (see Annex A).