How do I make a photograph of the sun?

[paulr]

there are filters available for telescopes that are designed specifically for this. maybe try a scientific supply or astronomy website? the trouble with homebrew solutions like welder's glass or exposed film is that you have no idea how much of the intense UV and other radiation is being filtered out. people have been known to hurt themselves (delayed onset injuries, like sunburned corneas, etc ... aslo called snowblindness, which is supposedly painful enough to get people to beg for death).

[Jim Galli]

John, I know you're.....OK, delicately, "thrifty" like myself. For a cheap solar filter try the foil your pop tarts are in. Don't even try to tell me you don't eat pop tarts. Photographer's breakfast of champions. 8>() Jim

[John Kasaian]

Thanks for all the ideas! WOW. I scoped out the websites and the sun photos I saw were inspiring. Do I take a reflected photo from a telescope(I have a wal-mart refractor) or take it straight on through the clouds using an aerial camera? I guess it will depend on what the circumstances are but I'm kind of leaning toward using the metal Gowland as it's already focus for infintiy and not as flammable as the 'dorff if I take it straight on. LOL Jim---Pop Tarts??? I wonder if the fillling they use on the chocolate ones are formulated from ersatz Rodinal?;-) What a great forum with all this expertese available. Thank you all!

[Steve Gangi]

I use a 4.5 inch (114mm)Newtonian relfector. A refractor works fine too. For this, a small camera (35mm or digital) is best. I mount the camera right at the focuser, where the eyepiece goes. This gives me a 900mm f8 lens. The adapter lets me insert an eyepiece between the scope and the camera, but then with that much magnification, vibration becomes a major issue, and just getting the sun into the frame becomes tricky. Here's some simple math, based on my system. Just as an example: Camera + scope = 900mm lens

Camera + scope + 30mm eyepiece: Magnification = 900mm scope / 30mm eyepiece = 30 (equivalent to 1500mm lens on 35mm camera)

I mounted the filter at the open end of the scope, the end that faces the sun. I meter with the camera. Of course this way, I can ignore all those charts you probably saw. Then I bracket anyway. For your refractor, take the focal length and divide it by the rated aperture. It can be inches or millimeters, so long as you are consistent. This yields the f-stop of your scope.