Described are methods, systems, and apparatus, including computer program products for locating one or more markers associated with IT equipment. An image of a scene including the one or more markers is acquired by a mobile computing device. A band-pass filter is applied by the mobile computing device to first pixel data associated with a first pixel in the image to generate a first band-pass filter result, wherein a pass-band of the band-pass filter is based on the light emitted by the one or more markers. A first pixel score is determined by the mobile computing device based on at least the first band-pass filter result. First indicia of the first pixel score is stored by the mobile computing device in a map at a first map location corresponding to a first image location of the first pixel in the image.