Evolution of human colour vision lights, which appear to be clear. Other colour perception issues include having trouble distinguishing yellows from reds and violet, lavender and purple from blue. In other cases, objects that reflect both red and blue light may appear to just be blue to these individuals. Deuteranopes, who are missing medium wavelength sensitive cones, are similar to protanopes in that they cannot distinguish between colours in the green-yellow-red part of the electromagnetic spectrum. However, deuteranopes do not suffer from dimming issues. For example, purple colors are not seen as being opposite to other colours in the spectrum but instead appear to be
Sky blue yellow in the middle". The sense of this colour may have been first used in 1585 in a book by Nicolas de Nicolay where he stated "the tulbant of the merchant must be "skie coloured"". Displayed at right is the web colour "sky blue". Celeste (, (, ) is the colloquial name for the pale turquoise blue colour associated with Italian bicycle manufacturer Bianchi S.p.A and sometimes known as "Bianchi Green". In Italian, as the name indicates (Celestial), it is an attempt to reproduce the colour of clear skies. In English, this colour may also be referred to as Italian