Hey Doug, He was taking darks through a thin plastic 2" cap on the end of the nose piece in a fully illuminated room... Those plastic caps, they are not light proof...
I had a near on identical looking dark frame from my ST10 when I did the exact same thing, thinking that the cap would be enough considering the camera had a shutter.. Not the case... I then put the camera into my scope and took darks with the metal cap on the scope - problem solved...