New methods for calculating acquisition illumination are computationally less expensive in comparison with conventional methods. In one such new method, source wavefield propagations are calculated and assigned to corresponding zero-offset receivers. Further, the number of non-zero-offset receivers within the coverage of the shot at the source location is decimated. Such a method is most advantages in reverse time migration, in which all source wavefield propagations are already calculated. The receiver-side illumination for each shot can be obtained by summing up all the source-side illumination with the source located within receiver coverage. All the source-side illumination and receiver-side illumination can be summed up to get the acquisition illumination for the survey. The acquisition illumination can be used to value the acquisition system and to compensate the migration images.