Imaging method for creating an image ( f j) of a region of investigation within an object, comprising the steps of: - collecting detector data ( y i) with a detector device of an imaging device, said detector data ( y i) comprising Poisson random values measured at an i -th of a plurality of different angular positions relative to the object, and - subjecting the detector data ( y i) to an image reconstruction method for reconstructing a tomographic image ( f j) of the region of investigation within the object, comprising the step of reconstructing the tomographic image ( f j) based on the detector data ( y i), said reconstructing step including a procedure of minimizing a functional F( f) depending on the detector data ( y i) and a system matrix A ij and additionally including a sparse or compressive representation of the object in an orthobasis T, wherein - the tomographic image ( f j) represents the global minimum of the functional F( f), and - the system matrix A ij is a predetermined matrix that assigns a j -th voxel of the object to the i -th detector data ( y i), defines the detector data as linear combinations of the original object data and is determined by geometric or physical features of an imaging device used for collecting said detector data ( y i), wherein - the system matrix A ij is determined using reference data of the imaging device or acquired using a calibration measurement performed with a calibration object having known volumetric object data, and - the reconstructing step includes a procedure of minimizing the functional F f _ = L y i, A ij f _ + a ‖ T T f _ ‖ wherein L({y ¡}, A ij f) is a maximum-likelihood risk functional for Poisson statistics, ∥ T T f ∥ is a sparsity enforcing functional including the l p norm of vector T T f with 0 ≤ p < 2, and a is a predetermined fixed calibration factor, and characterized in that - a preparation step is provided before the collection of the detector data, wherein the preparation step comprises setting of an image quality measure (r) to be fulfilled by the imaging method and, depending on the image quality measure, selecting the number of angular positions ( α l) at which detector data are collected. - collecting detector data ( y i) with a detector device of an imaging device, said detector data ( y i) comprising Poisson random values measured at an i -th of a plurality of different angular positions relative to the object, and - subjecting the detector data ( y i) to an image reconstruction method for reconstructing a tomographic image ( f j) of the region of investigation within the object, comprising the step of reconstructing the tomographic image ( f j) based on the detector data ( y i), said reconstructing step including a procedure of minimizing a functional F( f) depending on the detector data ( y i) and a system matrix A ij and additionally including a sparse or compressive representation of the object in an orthobasis T, wherein - the tomographic image ( f j) represents the global minimum of the functional F( f), and - the system matrix A ij is a predetermined matrix that assigns a j -th voxel of the object to the i -th detector data ( y i), defines the detector data as linear combinations of the original object data and is determined by geometric or physical features of an imaging device used for collecting said detector data ( y i), wherein - the system matrix A ij is determined using reference data of the imaging device or acquired using a calibration measurement performed with a calibration object having known volumetric object data, and - the reconstructing step includes a procedure of minimizing the functional F f _ = L y i, A ij f _ + a ‖ T T f _ ‖ wherein L({y ¡}, A ij f) is a maximum-likelihood risk functional for Poisson statistics, ∥ T T f ∥ is a sparsity enforcing functional including the l p norm of vector T T f with 0 ≤ p < 2, and a is a predetermined fixed calibration factor, and L({y ¡}, A ij f) is a maximum-likelihood risk functional for Poisson statistics, ∥ T T f ∥ is a sparsity enforcing functional including the l p norm of vector T T f with 0 ≤ p < 2, and a is a predetermined fixed calibration factor, and - a preparation step is provided before the collection of the detector data, wherein the preparation step comprises setting of an image quality measure (r) to be fulfilled by the imaging method and, depending on the image quality measure, selecting the number of angular positions ( α l) at which detector data are collected.