Al Paslow Astronomy Collection
Images and events of personal interest.
John Dobson on April 1, 2006 attended Astronomy Day at the Carnegie Science Center, in Pittsburgh PA. He gave a talk in the Planetarium followed by questions and answers to a good number of interested people.
A telescope mirror grinding demonistration was next using a 12.5 inch mirror blank.
Mr.Dobson's final stop was to tour Mingo Creek Park Observatory in Washington County PA.
Here are some images of the events:
A telescope mirror grinding demonistration was next using a 12.5 inch mirror blank.
Mr.Dobson's final stop was to tour Mingo Creek Park Observatory in Washington County PA.
Here are some images of the events:
The movement of the large 12.5 inch mirror blank, in this case in a "W" stroke accross the smaller 8 inch blank beneath it causes several things to occur. The big (top) mirror becomes concave, while the smaller miror (beneath) becomes convex. The curve diffrences is largely due to gravity.
The movement of the large 12.5 inch mirror blank, in this case in a "W" stroke accross the smaller 8 inch blank beneath it causes several things to occur. The big (top) mirror becomes concave, while the smaller miror (beneath) becomes convex. The curve diffrences is largely due to gravity.
Camera: Nikon (E990) |
More details: exif |
Original size: 2048px x 1536px |
Current: 400px x 300px |
in this box:This site features some great images.
