When etching circuit boards at home. I notice there is a small amount of bleed with the UV light and the mask.
I was thinking this could be sorted out by straightening the light, with a polarizing film. But I've never used any polarizing films before, and I'm just not sure what degree of film to use, or how many.
0 and 90 degree films seem to be the most popular, but if I'm correct, rotating the film will change the degree? I guess they are just labeled like that because they are for LCD screens, so you cant really rotate them.
Does anyone know what would be the best way would be, to only let light through that is going directly towards the PCB?