I need help trying to figure out what I am doing wrong. I am trying to use 1/1000 Shutter speed with Em-5 and Pany 35-100. Even though aperture is set to 2.8 and ISO auto (3200 or so), I still have the 2.8 blinking and the images are very dark. I need to reduce the Shutter value to about 160 for 2.8 to stop blinking. Do I need a faster lens or a flash for these conditions?