I have a problem with my loyal and very dear, ten year old Nikon F100. When I look through the viewfinder, all I see is a round black circle that appears to have the top one sixth sliced off. When I look more closely, it's as if a curtain has dropped down slightly over the entire screen. Also when viewed against bright light, the circle appears to be surrounded by a black shroud with faint pin lights. Also faint light can be seen around the square frame of the viewfinder. I am six hours by car from the nearest Nikon service. Any guidance would be most appreciated. Ten thousand thank yous in advance.