Aspects of the present disclosure include methods and systems for determining drop delay of a flow stream in a flow cytometer. Methods according to certain embodiments include obtaining a first frequency (f1) of drop perturbation of a flow stream subjected to an oscillating vibration, capturing one or more images of the flow stream in a detection field, obtaining a second frequency (f2) of drop perturbation of the flow stream based on one or more of the captured images and determining the drop delay of the flow stream based on the first frequency and the second frequency. Systems for practicing the subject methods having an imaging sensor for capturing one or more images of the flow stream and a processor configured to calculate drop delay using one or more of the captured images are also provided. Non-transitory computer readable storage mediums are also described.
