Method for determining main acquisition parameter and method for acquiring main x-ray image

The invention provides a method of determining a primary acquisition parameter and a method of acquiring a primary x-ray image. The at least one main acquisition parameter determines a dose of x-rays to be emitted from the x-ray emitter during main image acquisition using the x-ray emitter and the x-ray detector, the x-rays being used to image the object during medical image acquisition; the first image data of the first preliminary image is evaluated to determine whether a repetition condition is satisfied and/or to determine a main acquisition parameter and/or at least one second preliminary acquisition parameter; the first preliminary image is an image acquired by the x-ray detector using at least one first preliminary acquisition parameter for controlling the x-ray emitter; in all cases or only when a repetition condition is satisfied, a main acquisition parameter is determined from second image data of a second preliminary image, the second preliminary image being an image acquired by the x-ray detector