Method of MR imaging of at least a portion of an object placed in the examination volume of an MR device, the method comprising the steps of: - subjecting the portion of the object to a first stimulated echo imaging sequence comprising at least two preparation RF pulses (α) radiated toward the portion of the object during a first preparation period and a sequence of reading RF pulses (β) radiated toward the portion of the object during a first acquisition period temporally subsequent to the first preparation period; - acquiring a first set of FID signals (I FID) and a first set of stimulated echo signals (I STE) during the first acquisition period; - subjecting the portion of the object to a second stimulated echo imaging sequence comprising at least two preparation RF pulses (α) radiated toward the portion of the object during a second preparation period and a sequence of reading RF pulses (β) radiated toward the portion of the object during a second acquisition period temporally subsequent to the second preparation period; - acquiring a second set of FID signals (I FID) and a second set of stimulated echo signals (I STE) during the second acquisition period, wherein the first and second sets of FID signals (I FID) have different T 1 -weightings and/or the first and second sets of stimulated echo signals (I STE) have different T 1 -weightings; - deriving a B 1 map indicating the spatial distribution of the RF field of the RF pulses within the portion of the object from the acquired first and second sets of FID (I FID) and stimulated echo (I STE) signals, wherein the different T 1 -weightings are made use of to compensate for influences on the B 1 map caused by T 1 relaxation. - subjecting the portion of the object to a first stimulated echo imaging sequence comprising at least two preparation RF pulses (α) radiated toward the portion of the object during a first preparation period and a sequence of reading RF pulses (β) radiated toward the portion of the object during a first acquisition period temporally subsequent to the first preparation period; - acquiring a first set of FID signals (I FID) and a first set of stimulated echo signals (I STE) during the first acquisition period; - subjecting the portion of the object to a second stimulated echo imaging sequence comprising at least two preparation RF pulses (α) radiated toward the portion of the object during a second preparation period and a sequence of reading RF pulses (β) radiated toward the portion of the object during a second acquisition period temporally subsequent to the second preparation period; - acquiring a second set of FID signals (I FID) and a second set of stimulated echo signals (I STE) during the second acquisition period, wherein the first and second sets of FID signals (I FID) have different T 1 -weightings and/or the first and second sets of stimulated echo signals (I STE) have different T 1 -weightings; - deriving a B 1 map indicating the spatial distribution of the RF field of the RF pulses within the portion of the object from the acquired first and second sets of FID (I FID) and stimulated echo (I STE) signals, wherein the different T 1 -weightings are made use of to compensate for influences on the B 1 map caused by T 1 relaxation.