A method for characterizing a source of electromagnetic or ionizing radiation having a criterion (j), the criterion (j) being a criterion of a diffused radiation, and/or of a position of the source, which may be completed by the energy of the radiation, the method comprising the step of: - emitting the electromagnetic or ionizing radiation towards a semiconductor detector comprising at least two polarizing electrodes comprising an anode and a cathode; - generating electric signals under the effect of events of interaction of said radiation in said detector, each event being characterized, based on measurements of the electric signals, by at least one parameter (i); - determining a histogram of events including values (X(i)) according to the parameter (i), the values corresponding to numbers of detected events and the parameter (i) corresponding to a coordinate of the histogram; - determining, for each value (X(i)) of the histogram according to the parameter (i), a probability of acceptance P(Sj/Xi), indicating a probability to detect an event at the coordinate when the criterion (j) is met; - combining the histogram of the events and the probabilities of acceptance to give a new histogram of events corrected according to the probabilities of acceptance; - characterized in that the array of the probabilities of acceptance is obtained by two calibration in which the detector is irradiated by calibration radiations differing as to a criterion of acceptance of the events, the calibration radiations complying with the criterion (j) in a first of the calibrations and complying with the criterion (j) with a probability P in a second of the calibrations; - the calibrations giving two calibration histograms (P, P(X/S) used for calculating the probabilities of acceptance. - emitting the electromagnetic or ionizing radiation towards a semiconductor detector comprising at least two polarizing electrodes comprising an anode and a cathode; - generating electric signals under the effect of events of interaction of said radiation in said detector, each event being characterized, based on measurements of the electric signals, by at least one parameter (i); - determining a histogram of events including values (X(i)) according to the parameter (i), the values corresponding to numbers of detected events and the parameter (i) corresponding to a coordinate of the histogram; - determining, for each value (X(i)) of the histogram according to the parameter (i), a probability of acceptance P(Sj/Xi), indicating a probability to detect an event at the coordinate when the criterion (j) is met; - combining the histogram of the events and the probabilities of acceptance to give a new histogram of events corrected according to the probabilities of acceptance; - characterized in that the array of the probabilities of acceptance is obtained by two calibration in which the detector is irradiated by calibration radiations differing as to a criterion of acceptance of the events, the calibration radiations complying with the criterion (j) in a first of the calibrations and complying with the criterion (j) with a probability P in a second of the calibrations; - the calibrations giving two calibration histograms (P, P(X/S) used for calculating the probabilities of acceptance.