In a message dated 4/20/02 1:52:22 PM Mountain Daylight Time, rmcconahy@earthlink.net writes: << About 30 minutes before the transit I set off with a Meade ETX-90 telescope with a doubled-over piece of silverized Mylar over the front for a solar filter . . . One other problem was that the sun was still a little too bright in the scope, but I solved that problem by making a poor-man's neutral density filter by holding a pair of clip-on sunglasses between my eye and the ocular. >> Ralph -- I got chills reading this. I hope no one else attempts to watch a solar transit with a homebrew Mylar filter like this. Your eye is telling you something, I think, if there is too much light to view in comfort. Even if you are comfortable with a homemade filter, you can damage your eye and feel no pain, if IR and UV are excessive, as they easily could have been. Eyepiece mounted solar filters, exposed photographic film, smoked glass, pieces of compact disk, foil-coated wrappers: all are inappropriate in a solar telescope. Please spend the nominal $ to obtain a safe solar filter with a securely attached cell, and spare yourself the risk of of a scotoma in the middle of your visual field. Baader Astro-Solar film is inexpensive, available in sheets or mounted, and gives a solar image markedly superior to typical glass and Mylar filters. My view of sunspot detail and solar granulation markedly improved when I switched to the Baader film from a US-made glass unit. The sharpness and contrast are much better, and the color is neutral. In the US, it can be obtained from Astro-Physics; Jim Kendrick in Canada supplies it in cells. Perhaps Markus Ludes carries it Germany, or can recommend a source. Dan Laszlo Fort Collins CO ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www.satellite.eu.org/seesat/seesatindex.html
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