Thanks for your thoughts, but I would point out that I am filtering BEFORE the optical magnification (which is how most commercial telescope filters also work). You should never apply the filter after the primary or secondary lenses, as they can be damaged from direct exposure to the sun. But my research suggests that filtering before any optical magnification should be safe. With that said, it's always advisable to stick with buying commercial products, and I am not recommending this as a general use solution.