Ah, good point, Matt. I was shooting in daylight with a mix of bright light to deep shadow. I shot the same subject matter and conditions and often some of the same shot angles as I did with the converted Ricolet pinhole camera.
I believe this camera to meter through the lens. I did a quick test before beginning the shoot where I looked through the viewfinder at a scene with a broad spectrum of tone without the filter and then with the filter and noted about two f-stops difference in the metering. As I shot most shots in full "Program" mode, I figured the proper compensations would have been made by the camera's little brain. I have a Nikon N80 which meters through the lens and have used this orange filter with great results in manual, aperture priority and auto.
No markings of suggested compensation on the filter's outer ring or box. Though I will keep your note in mind when I use this filter on my Yashica Electro 35 which meters outside the lens, Moopheus. Should I have shot this roll in manual mode to further compensate regardless of the meter's reading?