1. A system for blur-calibration of an imaging sensor, the system having an optical axis in a focus direction, the system comprising: a target having a known target pattern comprising a plurality of point-like objects with fixed relative positions, at least one said point-like object having a different focus position in the focus direction along the optical axis; a projection element to project at least a portion of the target pattern within a field-of-view (FOV) of the imaging sensor; a controller configured to move the target pattern across the FOV; and image-capture elements to capture frames of images of the moving target pattern as seen in the FOV of the imaging sensor to sample point-like objects at different focus positions and generate a multi-focal image data output, wherein the controller is configured to cause the target pattern to move across the FOV to present the target pattern across different frames at different pixel phases, wherein the multi-focal image data output from the image-capture elements is subsequently processed to generate data products at different focus positions from high-resolution composite images generated from the captured frames for the different focus positions.