You know when you're dorking around with your Holga camera, scampering all over county fairs and train cars and up to the top of curly slides?
And you know how sometimes the local camera shop doesn't have any 120-medium format film in stock, just some *220* stuff with twice as many exposures, but no paper backing?
And you know how you then load the film into your toy camera and realize that the little red plastic window on the back -- the one that usually shows you what exposure you're on -- is now going to ruin your film because there's no paper backing to protect it?
So then you're at the part where you of course tape a piece of paper over the window, so as to keep light from bleeding through the red plastic and onto all your pictures.
The thing is... don't use a white piece of paper.
That doesn't, uh, really block light, you know.
However... once you've made this critical error, and noted with dismay the nasty stripe that runs through your entire, double-length roll of film when you pick it up from the camera shop...
For some reason once you scan the film and get it into Photoshop, if you convert it to black and white and then apply a "Blue Filter" in the program, it comes out looking pretty decent again.