Evolution of human colour vision similar. Tritanopes are missing the short wavelength sensitive opsins and see short wavelength colours in a green hue and dim compared to other colours. They may also see some short wavelength colours as black. Other perception problems include distinguishing yellow from pink or purple colours being perceived as shades of red. Researchers have found that trichromacy has advantages over dichromacy or anomalous trichromacy at further distances. This is believed to occur because visual cues such as shape decrease for colour vision as distance increases for targets of a smaller size. Using tests for spotting fruit pieces in bushes at distances
George Palmer (colour theorist) Leipzig four short works on various inventions, one being a fire-extinguishing powder. A demonstration in a pharmacy of the use of the powder was described in a Niedersachsen newspaper. In 1811 Palmer moved to Copenhagen into retirement and died there destitute in 1826. Palmer made a lasting contribution to the development of colour science by being the first to speculate that there are three different mechanisms in the human eye that account for colour vision: "The superficies of the retina is compounded of particles of three different kinds, analogous to the three rays of light; and each of these particles