please suggest me a method to determine the illumination of a room (with daylight and artificial lights, only daylight, only artificial lights) without using lux meter??

Question

anonymous · Answer

You could use a photoresister and measure the voltage drop across it. 

Obviously, you'd have to calibrate the photoresiter voltage curve to some quantifiable amount of light. Perhaps establish a minimum under starlight and a maximum under direct sunlight. You could readily find a photoresister that has a very linear response. You could then relate the voltage measured to the minimum or maximum value established.