All DOQ’s are referenced to the North American Datum of 1983 (NAD83) and cast
on the Universal Transverse Mercator (UTM) projection. Primary (NAD83) and secondary (NAD27) datum
coordinates for the upper left pixel are included in the header to allow users to spatially reference other digital
data with the DOQ. So, Digital Ortho Quarter Quads (DOQQ's) can be also used to geo-reference the images.