1. A computer implemented method of imaging, in an imaging system, comprising: a. acquiring a set of base data samples, b. operating on said set of base data samples with a predetermined reconstruction and obtaining a base result, c. performing perturbation at least one time to said set of base data samples and obtaining at least one set of perturbed data samples, d. operating individually on said at least one set of perturbed data samples with said predetermined reconstruction and obtaining at least one perturbed result, e. deriving an outcome based on said at least one perturbed result and said base result, whereby said outcome facilitates assessment and improvement of image quality.