1. A method for reconstruction of image data of an object under examination from measurement data, the measurement data having been captured during a relative rotational movement between a radiation source of a computed tomography system and the object under examination, the method comprising: computing first image data by modifying the measurement data to obtain a specific gray value characteristic of the first image data to be reconstructed, and computing the first image data by way of an iterative algorithm using the modified measurement data; and computing second image data by reconstructing a series of chronologically-consecutive images, and reducing temporal noise of the series of reconstructed images to form the second image data; and combining the first and the second image data.