Eyepieces For Telescopes
Beginner astronomers need to be careful with these items as they tend to go way overboard. There are various designs and different lenses for different viewings. You need to figure out what you will be looking at and go from there. You may need two to three different eyepieces, but no more than that. Here is a simple guide to the different eyepieces and cost involved.
The most popular is the Plossl. It uses four to five elements and have a wider field of view than Orthoscopic lenses. It usually ranges from 50-52 degrees. They run between $50-$150.
For general use, the Orthoscopic lenses were considered the best. They use four elements and are good for planetary viewing. They have a 45 degree field of view. They run between $40-$100.
The Kellner is a general purpose lens. It has a three element design and a 40-45 degree field of view. They run between $30-$50.
The Ramsden and Huygenian are good solar lenses. They have two element designs. They are supplied with the least expensive telescopes and have very narrow fields of view. They cost between $25-$40.
Barlow lenses are a great piece to have. They can double or triple the magnification of your eyepiece. They run between $60-$100.
Erfles are not as favorable today. They use six elements and a 60-65 degree field of view. They run between $75-$150.
Televue has come out with some designs for eyepieces. The six element Panoptic has a 67 degree field of view. It runs between $200-$400. The other is a seven to eight element Naglers. This lens has an 82 degree field of view and runs between $175-$425.
Pentax also makes a seven element lens, the SMC-XL, that runs around $250 each. It is thought that these exceed the what the Televues can do.
Telescopes
Viewing Deep Sky Objects And Comets
Achromatic Versus Apochromatic Lenses In Telescopes
Optical Features Of Telescopes
Telescopes
... its final home. It took three days and plenty of planning for it to arrive unscathed. The journey actually began when the mirror was spun cast in the giant rotating furnace back in 1997. The team at the Mirror Lab have been creating new mirror technologies for the past twenty years. After casting, it ...
... mounts for a heavier telescope. The second type of telescope mount is called the Equatorial. This mount uses two axes that are lined up with the poles to keep track of the motion an object takes across the sky. The axes can be Right Ascension, Polar, or Declination. Instead of moving up and down on its ...
Factors To Consider When Purchasing A Telescope
... is to make sure you know how to assemble it in the dark. Maintenance is upkeep of the telescope and its pieces. Probably the most common maintenance will be keeping the mirrors or lenses aligned properly. Also, the open ended telescopes are famous for collecting dust and debris. You may have to clean ...
Finding The Telescope That Meets Your Needs
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Historical Timeline For Telescopes
... possibly made from Visby lenses, a Middle Eastern glass. In 1520, Leonard Digges, an English mathematician, invented two telescopes Reflecting and Refracting. In 1608, A Dutch lens maker, Hans Lippershey, applied for a patent on a design for a telescope. In 1609, Galileo improved on Lippershey's design ...