C Cool Colours R 77 M Y B G C The cool colours of the Urbis building's glass façade (in Manchester, UK) were captured with a Nikon D100 Sigma 10­20mm f/4­5.6 EX DC HSM super wide angle zoom at 19mm, 1/1000 sec at f/6.7, ISO 200. Cool colours are those in the blue and blue-green segments of the colour wheel. This is based purely on a psychological association and has nothing to do with the colour temperature scale. Cold tone photographic paper has a distinct blue- black. Cool down filters ­ such as the Wratten Series 82 light-balancing filters ­ actually raise the numeric colour temperature, but they have the effect of making the image appear less warm, hence their name.