The quality of an illuminometer is related to its accuracy. Of course, it is also closely related to its price, so it is necessary to buy an accurate illuminometer at a reasonable price, generally with an error of no more than ± 15 percent .

The types of color compensation light sources are diverse, with some focusing on longer wavelength red high-pressure lamps or shorter wavelength blue purple lamps such as Daylight fluorescent lamps; There are also relatively evenly distributed incandescent light bulb series, where the sensitivity of the same illuminometer may vary slightly for different wavelengths, so moderate compensation is necessary.