Hi, I just bought an N90s with a Sigma 28-200 lens and the first few rolls of film came out great. I just got back 3 rolls I took today and out of 24 exp. each I have about 13 from each roll. Some frames are exposed correctly and some are blank, like the lens cap was on. Now sometimes when I'm taking pictures the viewfinder shows "Err" and the same thing in the LCD screen, it flashes "Err". When I take the roll of film out of the camera the Err goes away and the shutter speed and F stop shows as normal. Thanks for any help, Jake
