1. A method for representing a heart of a subject by magnetic resonance (MR), using an MR system, comprising the steps of: acquiring at least one MR overview image of a heart in an image plane having a predetermined position relative to the MR system; visually displaying the acquired MR overview image; allowing user interaction with the displayed MR overview image to manually mark five punctiform marking points at respective anatomical points in the displayed MR overview image; automatically electronically calculating three image planes each containing the long axis of the heart using only the five manually marked marking points; and acquiring further MR images respectively in the calculated three image planes.