The invention comprises both an x-ray unit and also a method for recording x-ray projection. The inventive x-ray unit is designed to move an object under examination along a longitu¬dinal axis at a forward velocity and further comprises a recording unit able to be rotated around the longitudinal axis. This recording unit comprises an x-ray emitter for emission of x-rays in the form of an x-ray bundle as well as an x-ray de¬tector for detection of the x-rays. The inventors have recog¬nized that a first, fixed-positonn slit aperture with a first opening of an extent D_1 along the longitudinal axis, designed for shaping the x-ray bundle with an extent DZ_1 at the height of the longitudinal axis, and also a second slit aperture with a second opening of an extent D_2 along the longitudinal axis, designed for shaping the x-ray bundle with an extent DZ_2 at the height of the longitudinal axis, wherein DZ_2