  We present observations of the Type Ia supernova SN 2002er during the
brightening phase. The observations were performed with the Potsdam Multi
Aperture Spectrophotometer (PMAS) integral field instrument. Due to the 8"*8",
field of view of the spectrograph an accurate background subtraction was
possible. Results from analyses of the evolution of absorption features in
comparisons with other SNe show that SN 2002er is a fairly bright Type Ia
supernova with a peak brightness of M_B=-19.6+-0.1.
