Dec

11

Dobsonian vs Newtonian telescopes

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Dobsonian and Newtonian telescopes are both reflector telescopes, utilizing a mirror and not lenses to see into space.

The term Newtonian refers to the actual telescope itself; whereas, the term Dobsonian refers to the telescope with its altazimuth mount.

An Altazimuth mount, also known as an alt-azimuth mount, is a very simple dual-axis telescope mount.

Dobsonian telescopes use a mechanically operated alt-azimuth mount, meaning that to move the telescope when navigating through space you literally push it and pull it up and down and left and right until you are pointing at what you want to see. The telescope moves smoothly due to the mount’s bearings and stays in place due to the mount’s friction and there are no parts to breakdown or wear out over time.

The only real disadvantage with a Dobsonian telescope is that it is tricky to track objects as they move through space, making it an impractical type of telescope to use for astrophotography.

Click Here for Dobsonian Telescopes at Amazon.com!

Click Here for Newtonian Telescopes at Amazon.com!

Dec

8

Why choose a reflector telescope?

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Reflector telescopes are a good choice for beginner astronomers.

Reflector telescopes, sometimes called Dobsonian or Newtonian telescopes, are great telescopes for those just getting started in astronomy for a number of reasons.

Generally, reflector telescopes are relatively inexpensive to produce, when compared to similar refractor telescopes and similar catadioptric telescopes.

The relatively low cost of reflector telescopes provides tremendous value, where you are not sacrificing optical quality or build quality for price.

You will be able to clearly see distant and faint objects that other similarly priced refractor telescopes and catadioptric telescopes would prevent you from seeing.

It is important to note that reflector telescopes use a mirror and not lenses, and that the top of the telescope tube is open, meaning that dust and debris can fall onto the mirror.  Also, on occasion, you will need to clean the telescope’s mirror and possibly even collimate it (realign it).

Click Here for Reflector Telescopes at Amazon.com!

Dec

5

Telescope upgrading

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What do you actually get when you upgrade from a child’s telescope to a beginner’s telescope or from a beginner’s telescope to an intermediate telescope?

Almost always, when you upgrade your telescope, you are paying for three elements; portability, optical quality and build quality.

For portability, you should expect your upgrade to lead you to a telescope that can easily be moved by one person while carrying it in one or two pieces, each weighing around 20lbs or less.

For optical quality, you should expect your upgrade to lead you to a telescope that has an aperture of f-8 or faster (meaning a number that is 8 or smaller), that has limited chromatic aberration (fringes of color around the image), no vignetting (dark corners of the image), no spherical aberrations (halos around the image) and no other distortions (dark or blurry images, etc).

For build quality, you should expect your upgrade to lead you to a telescope that is built with strong and lightweight materials that feel durable during use and the telescope should come attached to a very sturdy mount which offers smooth repositioning adjustments.

You may also find upgrades like on-board tracking computers, heaters to evaporate dew, GPS location systems and CCD imagers on higher priced telescopes.

Two telescope upgrades that we recommend are the Orion SkyQuest XT6 and the Orion SkyQuest XT8.

Click Here for Orion SkyQuest Telescopes at Amazon.com!

Dec

2

Planisphere

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Before you even purchase your first telescope, the very first thing that you need to buy is a plastic planisphere, or a star map, so that you can learn the constellations to be able to navigate your way through the night sky.

You need to purchase a planisphere for the correct hemisphere that you will be observing from, and also for the correct latitude that you will be observing from. For the northern United States, the 40-50 degree latitude star map will be sufficient, for other regions, determine the latitude that you will be observing the night sky from, and purchase the appropriate planisphere.

The number one reason for owning a planisphere is to be able to know what you are looking at, and to be able to navigate your way from object to object and from constellation to constellation without having to guess or rely on the auto-tracking computer system on your telescope.

Planispheres, or star maps, are around $10 and should not need to be replaced for many years, if ever.

Click Here for Planispheres at Amazon.com!