The color khaki dates way back in 1848, it’s name is a loanword from Hindustani that means ‘soil colored’, and in turn comes from the Persian word khak, meaning soil.
This earthy color was immediately used for sartorial purposes. Khaki was first worn among the British-Indian Army, taken from the idea of Sir Henry Lawrence, a governor-general stationed in India. Because of the severe temperature of India's climate, Lawrence wanted to wear garments that would be comfortable, lightweight, and one that would match the dust of India's terrain. Khaki became a famous color among the military after the British-Indian Army adopted it, followed by the United States Army until it became a common color among armies. Today, when you say khaki, you're also referring to the pair of slacks of tan-to-beige color.
With khaki being the original camouflage, it's easy to capture the color through photography, as there are many things in our natural world that are wearing khaki.However, if you're daring to drench your images with khaki, go for the Vandyke process or get a redscale film like the Lomography Redscale XR 50-200 :and pull the ISO to 50 or lower while taking images of light colors. You'll have a high chance of getting this dusty khaki color.