Hello, I experienced a strange film fog problem on my last exposures. I exposed an 8x10 neg. hp5+ in early morning light. Sun was at my back and up at about a 20 angle . I used my 300mm lens and a 21 orange filter in a Calumet gel holer clipped on the lens with barn door type shade. When I processed the film I got a one inch s trip that ran across the entire neg on one edge as though I was making a test st rip on paper( did not go to edges of film). I though at first it was a processin g problem (PMK) So next morning I went back and made two exposures with a diffen t holder same light conditions. Processed one neg. in PMK and one in hc110 and I got the same one inch strip on both negs. I then checked my camera all over for any leaks none found. I have since made other exposures with no problems. My on ly though is that I had some kind of internal reflection of light. What about th is type of filter holder reflecting light back into the lens? anyone had any pro blems of this type? Thanks Bill Bartels