Tilting of a drip chamber from its vertical axis during fluid administration can have negative effects upon the accuracy of systems configured for drop counting and/or for volumetric measurement of individual drops passing through the drip chamber. To address these negative effects, in accordance with one embodiment of the present disclosure, a fluid delivery system that measures the flow volume of a fluid delivery system is disclosed, which includes an imaging apparatus that captures a first image of a drip chamber while a drop is falling therein and a second image of the drip chamber with no drop. Portions of each image that are in substantially the same position in each image are subtracted.