Characterization of the CCD array of a digital camera for the purpose of spectral analysis of the sky gives the properties of the CCD sensor, such as response and spectral sensitivity. From the properties and characteristics, we can predict the spectrum, its power and power density from the captured image. In the research work, we took a digital camera and characterized it with a monochromator. We characterized it by capturing an image for each spectral component of the monochromator. We got a direct response from the pictures. We used the monochromator’s light source to calculate the spectral sensitivity of the sensor. The spectral sensitivity was then used to calculate the response at the reference spectrum. From the response at the reference spectrum, we calculated the sum of the values of all 3 colour channels and determined their ratio. The ratios of the colour channels of the reference spectrum were then used in the measurement of any light source. The captured image of the light source was characterized by calculating the sum of the values of every colour channel and then calculating the ratio between channels. The ratio was compared with the ratio of the response to the reference spectrum. By comparison, we were able to infer the shape of the incident spectrum and calculate an approximation of the incident power.
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