Method of ptychographic imaging, the method comprising: • providing an object in an object plane • providing a pixelated detector in a detector plane, the detector plane conjugated to the object plane by a Fresnel propagator, the detector equipped to detect the intensity of a wave front, • provide a radiation source and probe forming parts equipped to form an input wave front on the object plane, the input wave front transformed to an output wave front by the object, • provide a first mathematical estimate of the object, an estimate of the Fresnel propagator and an estimate of the input wave front, the mathematical estimate of the object represented by a number of nodes in a first calculation plane, each node a complex value, the method comprising: • acquiring at least two images by ∘ selecting an area of the object for irradiation, ∘ irradiating the area with radiation, ∘ detecting the intensity of a detector wave front on the pixelated detector, resulting in a detector image, ∘ each irradiated area overlapping with at least one other irradiated area, and iteratively • updating the mathematical estimate of the object such that, after multiplying the estimate of the object with the estimate of the input wave front in the first calculation plane and after propagating using the Fresnel propagator to a mathematical estimate of the image represented by a number of nodes of a second calculation plane, the detected intensity of a pixel of the detector image matches the intensity of the corresponding area of the mathematical estimate of the image in said second calculation plane for the at least two images, until a break-off criterion is met, characterized in that a pixel of the detector image corresponds to more than one node of the second calculation plane, and during the update the measured intensity of each detector pixel is made to match the intensity of the corresponding number of nodes. • providing an object in an object plane • providing a pixelated detector in a detector plane, the detector plane conjugated to the object plane by a Fresnel propagator, the detector equipped to detect the intensity of a wave front, • provide a radiation source and probe forming parts equipped to form an input wave front on the object plane, the input wave front transformed to an output wave front by the object, • provide a first mathematical estimate of the object, an estimate of the Fresnel propagator and an estimate of the input wave front, the mathematical estimate of the object represented by a number of nodes in a first calculation plane, each node a complex value, • acquiring at least two images by ∘ selecting an area of the object for irradiation, ∘ irradiating the area with radiation, ∘ detecting the intensity of a detector wave front on the pixelated detector, resulting in a detector image, ∘ each irradiated area overlapping with at least one other irradiated area, ∘ selecting an area of the object for irradiation, ∘ irradiating the area with radiation, ∘ detecting the intensity of a detector wave front on the pixelated detector, resulting in a detector image, ∘ each irradiated area overlapping with at least one other irradiated area, • updating the mathematical estimate of the object such that, after multiplying the estimate of the object with the estimate of the input wave front in the first calculation plane and after propagating using the Fresnel propagator to a mathematical estimate of the image represented by a number of nodes of a second calculation plane, the detected intensity of a pixel of the detector image matches the intensity of the corresponding area of the mathematical estimate of the image in said second calculation plane for the at least two images,