The following values produce a fair approximation to the Meteosat Second Generation (MSG) space view. It is only approximate because the proj4 nsper projection assumes a spherical earth. (This isn't the case for the usual proj4 map projections which are generally very accurate.)
width=3712 height=3712
proj=nsper a=6367.453 h=34700.0 to_meter=3.0137 lon_0=0.0 lat_0=0.0 x_0=5591.92 y_0=5591.92