This is an old mosaic of the North America and Pelican nebulae. The red is due to the Lumicon Sky nebular filter in the same train with the Kodak Royal Gold 400-2 film. The same nebular filter did better with the Kodacolor emulsions of the 1980's. One thing, this filter shifted in response over time and this was noted shortly after these exposures were taken by others who published data on the available nebular filters. The newer filters shows less shift over time. 10" F/4.5 Newtonian with an Olympus OM-1 camera. Mosaic of 5 images of 30 minutes each on 9-2-2000. Lumicon Sky filter on the Lumicon field flattener and Easy Guider I still use.
The dark sky site at the time. The old Meade mount. This is what I had to deal with. We had a full complement that night, mosquitoes carried some away.