Photographic photometric methods define magnitudes and colours of astronomical objects using astronomical photographic images as viewed through selected or standard coloured bandpass filters. This differs from other expressions of apparent visual magnitude observed by the human eye or obtained by photography: that usually appear in older astronomical texts and catalogues. Early photographic images initially employed inconsistent quality or unstable yellow coloured filters, though later filter systems adopted more standardised bandpass filters which are still used with today's CCD photometers.