Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Solar Filters and Camera

  1. Aug 28, 2003 #1
    I have been thinking about picking-up two things for my telescope. A camera adapter and solar filter.

    How much does a good solar filter usually cost (one that I can buy at a store, not on the internet)? Where can I purchase one? I also hear that one should never buy one that goes over the eyepiece, but over the front of the telescope instead.

    How much does an adapter cost to connect a digital camera to a telescope?
  2. jcsd
  3. Aug 29, 2003 #2
    I never trust the filters
    but to look at sunspots I just project the image on a sheet of paper
    even with a very small scope you can get a large image that way and it is both totaly safe and free
    just hold a sheet of paper about 1 to 3 feet away and move it intill you get a sharpe image
  4. Aug 29, 2003 #3
    Project from my telescope? Won't this destroy the inside?
  5. Aug 30, 2003 #4
    NO it will not unless you have a plastic lenz or mirror and will protect your eyes from uv-rays

    you can also use a cheap pair of bi-knocks
    and get a large immage that severial people can see at once with nice sharp sun spots by projecting on paper
  6. Aug 31, 2003 #5


    User Avatar
    Science Advisor

    Very many high-cost eyepieces have been ruined by "solar projection". Even in the good glass, some elements in some designs are cemented (glued), and the heat from the objective can destroy the cement and/or break the glass.

    A full-aperture solar filter is safe if reasonably well made. Two US companies make glass filters of different sizes, but most people now use the "film" filter material from Baader, in Germany. It gives higher resolution, and it even comes with instructions on how to make a filter cell from a few $ worth of glue and paper. Very safe and very high resolution.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook