Corrective filters designed as conversion filters will increase or reduce the colour temperature of the light source due to the spectral progression of the transmission. Skintone filters only correct the lamp's light spectrum in the green and yellow spectral range and thereby produce a very natural and pleasant effect on skin tones. Daylight-conversion filters transform the warm white colour temperature in the range of the neutral white colour of light, i.e. from 3000K to 4000K.