A bar code reading device having an image sensor including a plurality of pixels can be operated to capture a parameter determination frame of image data, wherein the parameter determination frame of image data includes image data corresponding to light incident at less than all of the pixels of the image sensor. A bar code reading device can also be operated in an image capture operating mode in which a partial frame of image data is captured, wherein the partial frame of image data includes image data corresponding to light incident at less all of the pixels of the image sensor, and wherein image data of the partial frame can be processed in order to attempt to decode a bar code symbol.