are you using the bayo mount fisheye or the screw mount fisheye? if screw mount then yes you can add more spacer rings. if you are using the bayonet mount, you can take it off and use multiple spacer rings. im just not sure what the ring size is underneath. may be 77, in which case you'd need a couple 77mm rings and a 77-62mm step down ring. even more important though are your settings. you seem to be in full auto mode.