Ordinary glass lenses transmit most of the light that hits them, but even so, about 4% of this light is lost to surface reflection. Since lenses have front and rear surfaces, this means that the overall loss of light from passing through one lens element is 8%. Most camera lenses are made up of five to 10 elements, and so in the end, the total amount of light getting through the lens is reduced by about 50%. Lens coatings were developed to prevent surface reflection and boost light transmission. Coating lenses enables more light to pass through them.