An electronic device comprising: an image sensor comprising: a plurality of first pixels configured to receive light for a first time duration, and a plurality of second pixels configured to receive light for a second time duration shorter than the first time duration; and at least one processor (120, 230), characterized in that the at least one processor is configured to: acquire first raw data from the image sensor, wherein the first raw data comprises first long pixel values acquired through the plurality of first pixels and first short pixel values acquired through the plurality of second pixels, acquire second raw data from the image sensor, wherein the second raw data comprises second long pixel values acquired through the plurality of first pixels and second short pixel values acquired through the plurality of second pixels, and acquire third raw data based on the first raw data and the second raw data, wherein the third raw data includes third long pixel values and third short pixel values, wherein each of the third long pixel values is an average value of a first long pixel value of the first long pixel values at a first pixel location and a second long pixel value of the second long pixel values at the first pixel location, and wherein each of the third short pixel values is a value obtained by gamma correcting a sum of a first short pixel value of the first short pixel values at a second pixel location and a second short pixel value of the second short pixel value at the second pixel location. an image sensor comprising: a plurality of first pixels configured to receive light for a first time duration, and a plurality of second pixels configured to receive light for a second time duration shorter than the first time duration; and a plurality of first pixels configured to receive light for a first time duration, and a plurality of second pixels configured to receive light for a second time duration shorter than the first time duration; and at least one processor (120, 230), characterized in that the at least one processor is configured to: acquire first raw data from the image sensor, wherein the first raw data comprises first long pixel values acquired through the plurality of first pixels and first short pixel values acquired through the plurality of second pixels, acquire second raw data from the image sensor, wherein the second raw data comprises second long pixel values acquired through the plurality of first pixels and second short pixel values acquired through the plurality of second pixels, and acquire third raw data based on the first raw data and the second raw data, wherein the third raw data includes third long pixel values and third short pixel values, wherein each of the third long pixel values is an average value of a first long pixel value of the first long pixel values at a first pixel location and a second long pixel value of the second long pixel values at the first pixel location, and wherein each of the third short pixel values is a value obtained by gamma correcting a sum of a first short pixel value of the first short pixel values at a second pixel location and a second short pixel value of the second short pixel value at the second pixel location. acquire first raw data from the image sensor, wherein the first raw data comprises first long pixel values acquired through the plurality of first pixels and first short pixel values acquired through the plurality of second pixels, acquire second raw data from the image sensor, wherein the second raw data comprises second long pixel values acquired through the plurality of first pixels and second short pixel values acquired through the plurality of second pixels, and acquire third raw data based on the first raw data and the second raw data, wherein the third raw data includes third long pixel values and third short pixel values, wherein each of the third long pixel values is an average value of a first long pixel value of the first long pixel values at a first pixel location and a second long pixel value of the second long pixel values at the first pixel location, and wherein each of the third short pixel values is a value obtained by gamma correcting a sum of a first short pixel value of the first short pixel values at a second pixel location and a second short pixel value of the second short pixel value at the second pixel location.