Finished my solar filter for tomorrow. Then shock horror, on close inspection at a halogen desk lamp: pinholes!! Not just one or two either, but quite a few! Now I'm looking up Baaders info, and their instructions actually state:
Quote:
...inspect the cell for light leaks prior to using it on your telescope or binoculars. You must be sure that absolutely no unfiltered light gets through. Use a black felt-tip marker on the inside of the filter (for esthetic appearance) to cover tiny pinholes in the filter material. Now
your “do-it -yourself” filter is ready. Enjoy!
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So they are actually expecting you to find pinholes in the stuff! .. and a black marker to save you from blindness! okay I know I'm exaggerating, few small pinholes will not cause blindness, but still, I appreciate why some dealers refuse to stock the stuff and insist on solid glass filters.
So it's a stop off at the newsagent's for a permanent marker before work tomorrow. (although the forecast is not looking too good)