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View Full Version : Astrophoto: NGC 7048 by Stefan Heutz



Fraser
2006-Sep-21, 10:34 PM
The ability for convex and concave transparent objects to enlarge or reduce had been known since Antiquity and by the end of the thirteenth century; quality glass was relatively inexpensive, particularly in Italy. At the same time, techniques for grinding and polishing had reached a high state of relative precision in Venice. So, handheld magnifying glasses became relatively common. During the fourteenth century, the craftsmen of Venice began producing small double-sided convex glass disks that could be mounted and worn in a frame- the first reading glasses. By the middle of the fifteenth century the Italians were also producing spectacles that corrected for nearsightedness. Therefore, around 1450 the ingredients to produce the first telescope were in place but it would be another 150 before children would trigger its invention and change everything.

Read the full blog entry (http://www.universetoday.com/2006/09/21/astrophoto-ngc-7048-by-stefan-heutz/)