Evolution of human colour vision that are found between 450 and 625. Individuals with various forms of colour blindness such as deuteranopia and protanopia are missing human middle wavelength sensitive or long wavelength sensitive opsins. Their minimum wavelength differences are <5 but only at around 500. Protanopes, who are missing long wavelength sensitive cones, are unable to distinguish between colours in the green-yellow-red section of the electromagnetic spectrum. They find yellow, red and orange colours to have much lower brightness when compared to a trichromat. The dimming of these colours can result in confusion in many cases, such as when attempting to identify red traffic
Colour sergeant as "Colour Sergeant" or "Colours" in the Royal Marines, and never by the more junior rank of "Sergeant". Unusually, NCOs with the rank of colour sergeant who hold the appointment of company quartermaster sergeant are still addressed and referred to by their rank, not their appointment. In Foot Guards regiments, colour sergeants are addressed as "Sir" and afforded the respect and privileges normally accorded to warrant officers. During ceremonial events it is from the colour sergeant that the ensign collects the colour of the battalion or regiment. In the Royal Marines Band Service, the bandmasters of the seven Royal Navy