Ensemble photometry is a technique to measure the brightness or flux of a target star by comparing the flux of the target object to the combined flux of multiple Reference stars, forming an "ensemble" of Reference stars. These Reference stars have to be non-variable stars in the vicinity of the target star.


By utilizing multiple Reference stars, ensemble photometry can help mitigate various sources of error and uncertainties, including atmospheric conditions, instrumental effects, etc. It is said to provide a more robust and accurate measurement of the target star's flux than using single-star photometry.


Phoranso supports both single-star photometry (when you select exactly one Reference star) and ensemble photometry (when you select multiple Reference stars).