The invention relates to a device for adjusting imaging parameters of an
X-ray apparatus (1), whereby a user pre-defines on a preliminary image an
image region of interest (ROI) and a value of the contrast-to-noise ratio
(CNR.sub.ref) desired for this image region. Based on the current
contrast-to-noise ratio (CNR.sub.m), new imaging parameters (I, V, L, f,
Q.sub.0) are then calculated for a generator-control module (7) to
control the X-ray apparatus (1) during an image. By means of the method,
the X-ray dose may be reduced to a minimum, while at the same time the
desired visibility of a region of interest is ensured.