As in other Canon PS case, the ver.req file works as well in this model. Press FUNCSET and DISP simultaneously: It shows the following: Canon PowerShot SX1 IS P-ID:3195 PAL D Firmware Ver GM2.00H NoError Feb 4 2009 10:41:18 Subsequent press of DISP (while still holding FUNCSET) reveals: Adj Ver.021.000 Subsequent press of DISP (while still holding FUNCSET) reveals: SubCPU Ver. 1.01 IS Firm Ver. 3.03 IS Param Ver. 3.00 VcmCPU Ver 0.42 If you use vers.req instead of ver.req at the last screen you can see more info: Firmware Ver. 2.0.0.0 [ OK ]