On Wednesday, 2002/4/24, I was able to see what I believe was AR 9915 without magnification through polymer solar eclipse shades. (IOW, it was a "naked-eye" sunspot but don't any of you dare to try to view it without a proper filter!) Instead of my 114mm f/7.9 C4.5 Newtonian I used my 80mm f/5 Orion ShortTube 80 achromat with an approximately 43mm diameter Baader solar filter at 24x (17mm Tele Vue Ploessl), 36x (11mm Tele Vue Ploessl), and 57x (7mm Siebert Koenig). There were five or six medium to large sized sunspots and several small ones. AR 9915 had multiple umbrae.
The transparency and seeing were better than on Tuesday afternoon and the temperature and pressure were 15 degrees Celsius and 1016 millibars.
Despite the better filter (I have a full aperture Mylar filter for the C4.5) and the refractor's lack of central obstruction, the diminished resolution of a much smaller aperture was noticeable.
See http://www.spaceweather.com/images2002/24apr02/midi512_blank.gif for an image.
Dave Mitsky
Harrisburg, PA
The transparency and seeing were better than on Tuesday afternoon and the temperature and pressure were 15 degrees Celsius and 1016 millibars.
Despite the better filter (I have a full aperture Mylar filter for the C4.5) and the refractor's lack of central obstruction, the diminished resolution of a much smaller aperture was noticeable.
See http://www.spaceweather.com/images2002/24apr02/midi512_blank.gif for an image.
Dave Mitsky
Harrisburg, PA
Chance favors the prepared mind.
De gustibus non est disputandum.
