I need help with troubleshooting a DIY blocking filter for Natural light.
I modified a Canon Powershot A490 to shoot only IR. I removed the IR-block filter (right in front of the CMOS), and installed exposed undeveloped film. I've read that two cheap Natural light block filters are either exposed, undeveloped film or unexposed, developed film. one is supposed to provide clearer images... I installed exposed undeveloped film in the same location the IR-block used to be.
As per request, the information was added. The film was exposed to natural light (in a whole roll) and from there, I made a point of carefully selecting patches from which to cut the film. Extreme care was made to ensure the CMOS, and film was not tainted by dust and finger oil. The CMOS retainer has a small "compartment" recessed into the lens housings where the original filter was. I placed the film in the recessed area, which has a small rubber seal fitting between the CMOS and the next lens (which remains untouched). The film has no gap that would otherwise let in light. Originally I used three strips of film, but upon activation found that the camera had no light coming in at all. I cut it down upon that to one square of film (correctly sized).
The camera does work- exactly as a camera should- with this one tweak. The film has a purple blur near the edges of the camera, and it is hard to focus/see the subject of the photo I am going to take. This is a little frustrating as you can see... I know IR is gonna have a red tint to it, but nothing I've seen has had this intensity of tint. If you can advise me to a cheap yet effective solution, I would be extremely grateful.
Update (sorry school has taken priority lately) After some more testing, I can conclude that I was using the wrong type of film. Unless I am mistaken, I believe that the film reduces most IR input due to the silver content in c-41 process film and does not block all natural light (I have found true-color in a photo by comparing it with the photo subject). I have done some more research and believe that unexposed, developed c-6 process (slide film? I am going off of memory here) would be better. It allows IR to pass through, and because there would be no exposure, it would be filled with dye, obstructing natural light.
This is an experiment. I will update with any info I find, but any added input is extremely helpful.