A photographing apparatus, comprising: a photographing unit configured to produce an image signal based on an optical information received from an object to be photographed; a signal processing unit configured to receive the image signal from the photographing unit and to perform a signal processing on the received image signal to produce image data; a codec configured to receive the image data from the signal processing unit and to compress the received image data to produce a compressed image data; a storage unit configured to store therein the compressed image data; an auto focus sensor configured to generate AF data; and an AF control unit to control focusing of the photographing unit using the AF data generated by the AF sensor, wherein the AF sensor includes a plurality of AF pixels and a light exposure control unit, each of the plurality of AF pixels comprising: a light-receiving element configured to receive a portion of light incident on the photographing unit and to produce an output in response to the received portion of light; and a circuit element (Tr1, Tr2, Tr3, Tr4) configured to generate the AF data using the output of the light-receiving element, characterized in that each of the plurality of AF pixels further comprising: a capacitor (C MON) connected to the light-receiving element, and wherein the light exposure control unit is configured to receive from each of AF pixels among the plurality of AF pixels an information about an amount of light received by the light-receiving element of the respective one of the AF pixels, and wherein the light exposure control unit comprises a light exposure time adjustment unit, the light exposure time adjustment unit being configured to control light exposure of the plurality of AF pixels based on the received information about the amount of received light, wherein the information about the amount of received light of the light-receiving element comprises a level electrical charge present in the capacitor (C MON) a photographing unit configured to produce an image signal based on an optical information received from an object to be photographed; a signal processing unit configured to receive the image signal from the photographing unit and to perform a signal processing on the received image signal to produce image data; a codec configured to receive the image data from the signal processing unit and to compress the received image data to produce a compressed image data; a storage unit configured to store therein the compressed image data; an auto focus sensor configured to generate AF data; and an AF control unit to control focusing of the photographing unit using the AF data generated by the AF sensor, wherein the AF sensor includes a plurality of AF pixels and a light exposure control unit, each of the plurality of AF pixels comprising: a light-receiving element configured to receive a portion of light incident on the photographing unit and to produce an output in response to the received portion of light; and a circuit element (Tr1, Tr2, Tr3, Tr4) configured to generate the AF data using the output of the light-receiving element, characterized in that each of the plurality of AF pixels further comprising: a capacitor (C MON) connected to the light-receiving element, and a light-receiving element configured to receive a portion of light incident on the photographing unit and to produce an output in response to the received portion of light; and a circuit element (Tr1, Tr2, Tr3, Tr4) configured to generate the AF data using the output of the light-receiving element, each of the plurality of AF pixels further comprising: a capacitor (C MON) connected to the light-receiving element, and a capacitor (C MON) connected to the light-receiving element, and