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Telescope : Celestron 21037 PowerSeeker 70EQ
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Technical Details
* Brand Name: Celestron
* Model : 21037
Product Details
# Product Dimensions: 39 x 13 x 10 inches ; 15 pounds
# Shipping Weight : 22 pounds (View shipping rates and policies)
# ASIN : B001592LFC
# Item model number : 21037
Product Description
Product Review Celestron’s PowerSeeker 70 EQ telescope combines the solid optical performance of a classic achromatic refractor with a light weight equatorial mount. This telescope has half the light gathering power and half the weight of Celestron’s classic C102 refractor telescope, for much less than half the cost.
With fully coated optics and an image correcting diagonal prism, the PowerSeeker 70 EQ shows delightfully crisp daylight views when I use the low power 20mm eyepiece (35x magnification).
With my Powershot camera I can take pictures of birds as close as 30 feet away, and with my NexImage CCD the Moon and planets show only a little false color at high magnification. The high power 4mm eyepiece (175x magnification) shows surprisingly good close-up views of the planets. When I look at the Moon for instance, I can easily pick out details like the mountain peaks and terraced walls inside Crater Copernicus. My view of Saturn shows Saturn’s rings plainly separated from the planet, and bright double stars like Castor in the constellation Gemini and Algieba in Leo are cleanly split into two tiny beads of light.
The PowerSeeker equatorial mount is a light weight model but it handles the 70mm optical tube reasonably well. Vibrations are noticeable when I touch the focus knob, but the image stabilizes in about two seconds which is quite acceptable. Some of the other accessories included with the PowerSeeker 70 EQ are less inspiring. The finder scope seems to be all plastic; I needed to wrap a little tape around the finder to make it fit properly in its bracket. The worst accessory in my view is the 3x barlow. No doubt Celestron includes this 3x plastic barlow to compete with the so-called '500 power' 'professional model' telescopes found in toy stores. I'd prefer to see a nice 10mm eyepiece for 70x magnification included instead of the 3x barlow.
Overall the PowerSeeker 70 EQ is a really nice addition to Celestron’s value priced PowerSeeker series. Of all the PowerSeekers I like this one best because of its fine optical performance and because the accessories are solid enough to be truly usable. This is a real telescope and it’s capable of serving up delightful views to the junior astronomer or the family on a budget. --Jeff Phillips
Pros:
• Surprisingly good optics
• Correct image diagonal included
• EQ mount with slow motion controls
• High and low power eyepieces
Cons:
• Plastic finder scope
• Plastic 3x barlow
Product Description
70mm (2.8") diameter refractor, 700mm focal length (f/10), German equatorial mount with RA and DEC slow-motion controls and setting circles, 5x24 finderscope, 20mm eyepiece (35x) - 1-1/4", 4mm eyepiece (175x) - 1-1/4", erect image diagonal - 1-1/4", Barlow lens 3x - 1-1/4", adjustable aluminum tripod with accessory tray, "The Sky Level 1" CD-ROM. Metallic charcoal black tube color.
Introduction to Telescope
What is Telescope ?
according definition from Wikipedia, the free encyclopedia
A telescope is an instrument designed for the observation of remote objects by the collection of electromagnetic radiation. The first known practically functioning telescopes were invented in the Netherlands at the beginning of the 17th century. "Telescopes" can refer to a whole range of instruments operating in most regions of the electromagnetic spectrum.
The word "telescope" (from the Greek τῆλε, tele "far" and σκοπεῖν, skopein "to look or see"; τηλεσκόπος, teleskopos "far-seeing") was coined in 1611 by the Greek mathematician Giovanni Demisiani for one of Galileo Galilei's instruments presented at a banquet at the Accademia dei Lincei.In the Starry Messenger Galileo had used the term "perspicillum".
Introduction to Binoculars
A typical Porro prism binoculars design
What is Binoculars?
From Wikipedia, the free encyclopedia
Let's visit definition in wikipedia
Binoculars, field glasses or binocular telescopes are a pair of identical or mirror-symmetrical telescopes mounted side-by-side and aligned to point accurately in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects. Most are sized to be held using both hands, although sizes vary widely from opera glasses to large pedestal mounted military models. Many different abbreviations are used for binoculars, including glasses, binos and bins.
Unlike a (monocular) telescope, binoculars give users a three-dimensional image: for nearer objects the two views, presented to each of the viewer's eyes from slightly different viewpoints, produce a merged view with an impression of depth. There is no need to close or obstruct one eye to avoid confusion, as is common with monocular telescopes. The use of both eyes also significantly increases the perceived visual acuity (resolution), even at greater distances where depth perception is not apparent.
Labels:
binoculars,
introduction