13 votes
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Could someone explain what is wrong with my telescope, and what should I be able to see with it?

Welcome to the wonderful world of visual astronomy! The first thing I would like to point out is that, when you are talking about “zooming in,” you’re actually adjusting focus—placing the eyepiece ...
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12 votes
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What's the difference between a Newtonian telescope and a regular telescope

First off, I would not recommend any of these telescopes. Of the ones you listed, the 114EQ is the least bad choice. But, due to the poor quality of its mount, it's the better of the bunch. Ok, ...
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11 votes

Could someone explain what is wrong with my telescope, and what should I be able to see with it?

I suggest you take your scope out during the day and look at the most distant object on land (or sea) that you can see: a building, tower, or tree. Start with the 25 mm eyepiece and turn the focus ...
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  • 7,180
10 votes
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How much of a difference do good lenses make?

...a very blurry, small view of Jupiter with the 4mm and Barlow... Be aware that a 4mm eyepiece and a 3x barlow at the same time will give you a very high magnification - too high! For regular ...
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  • 2,377
9 votes
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Mars looks like a blur

There's another answer here claiming that an off-axis aperture mask will improve things. That is a fairly popular meme, but it's entirely incorrect, and makes misleading claims about the effects of ...
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9 votes
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Betelgeuse appears in a rainbow of colors through a Newtonian telescope

...pulsing bright rainbow of colors... Sounds like very bad astronomical seeing effects. Even a steady atmosphere acts like a weak prism and in fact all dielectrics tend to bend blue light more than ...
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7 votes
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How do I remove fungus from a telescope mirror?

Several points need to be made. 1. Performance The performance of the whole optical stack is incredibly resilient w.r.t. small spots on the primary mirror. The mirror might look visually very, very ...
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6 votes

Dish antenna as parabolic mirror for OPTICAL telescope?

I would have added this as a comment (not enough rep yet, I'm afraid)... To elaborate on Andy's answer, the first reason is that the surface of the satellite dishes are too coarse to form any kind of ...
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6 votes

Dish antenna as parabolic mirror for OPTICAL telescope?

It's not possible I'm afraid. Optical wavelengths (light) are typically of a wavelength under a micron, and an optical surface needs to be accurate to this level or better to be useful. Radio ...
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  • 2,377
6 votes
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Why are Cassegrain telescopes shorter than Newtonian reflecting telescopes?

Basically, the light has a longer way to go after hitting the secondary mirror in a Cassegrain than in a Newton telescope. In a Newton telescope (top image), the light hits the primary mirror and ...
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5 votes
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I need help getting mars to look like a circle

I have made sure that the laser is straight by 1. spinning it in the eyepiece holder and the laser stayed in the same spot 2. zooming in and out and again the laser stayed in the same place. the ...
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5 votes
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Under what situations can an aperture mask improve the resolution of a small/medium amateur telescope? Is this demonstrable mathematically?

The vast majority of people - almost everyone, really - should not rely on this on a daily basis. The chances are overwhelming that they will reduce the performance of their instruments. There are so ...
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5 votes
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Help stabilizing telescope

A "Celestron Powerseeker 114AZ" Google turns up old reviews at Amazon.com and .ca. Most are somewhat critical of the mount. In all honesty that is to be expected at this level. Many amateur ...
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5 votes

Could someone explain what is wrong with my telescope, and what should I be able to see with it?

Even if your telescope is correctly set up, its short focal length of 650mm is not ideal for observing details of the moon and planets. You should get one or two more eyepieces with a shorter focal ...
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  • 2,318
5 votes
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How to locate M13, Ring Nebula?

The ring nebula (also called M57) is quite beautiful and relatively easy to find! It is located in the constellation Lyra---which will be easy to find since it has one of the brightest stars in the ...
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4 votes

Difficulties in finding Jupiter

Go out in the daytime and practice lining up on the leaves of trees on a distant hill or some such. It's easier to find targets when they aren't against a nearly featureless black backdrop. If you ...
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4 votes

Why are Cassegrain telescopes shorter than Newtonian reflecting telescopes?

The Focal Length is not really the distance the light travels from the objective. The Focal Length is the diameter of the aperture divided by the tangent of the angle at which light rays from the ...
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3 votes

Advice on first Telescope (refractor vs reflector), Barlow lens

Further would a Barlow lens solve the chromatic aberration issues with a f/5 refractor. I suppose in theory they could, but they would have to be designed to do so. In practice, they vary widely in ...
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  • 701
3 votes

What's the difference between a Newtonian telescope and a regular telescope

A "Newtonian" reflector has a main mirror which is curved and focuses the light back up the tube. It then has a secondary flat mirror at an angle which reflects the image sideways. A Newtonian ...
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  • 91.5k
3 votes
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Collimating with a home-made collimation cap

The Gary Seronik website that you cite is a good one - it's not leading you astray! There are a couple of important things to look at: Look straight down the main tube of your telescope at the ...
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  • 634
3 votes
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Newtonian reflector collimation question

Your scope is f/5. There will always be some coma aberration. Always, the image quality is worse as you get closer to the edge of the field of view (FOV). Personally, given that the fact that you will ...
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  • 316
3 votes
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Why does any planet look like a (not so) big white ball through my telescope?

It seems that you haven't align properly your finder (or) laser. You can align at day with a chimney, but at night you must start with the moon and after that you are sure that you are pointing ...
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3 votes
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Why does the focal length of a telescope have an effect on the magnification?

The objective lens of a telescope forms an real image of the night sky, the size of that image is in proportion to the focal length of the objective lens. The reason for this is simple geometry: If ...
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3 votes
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Is the angular resolution of a telescope irrespective of used eye-piece?

The resolution of a telescope is the resolution of the image created by the primary mirror at the focal plane. It provides the minimum separation between two equal brightness stars that appear ...
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  • 2,857
3 votes
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Did Edmund Scientific 4¼ inch Newtonians have 90° prisms as secondary mirrors in the 1970's?

My Edmund F/10 4 1/4" was bought in 1975, and had a rectangular front-surface mirror as the diagonal, with a single arm support attached to the tube near the eyepiece holder. I believe the Astroscan ...
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  • 2,831
3 votes

Best telescope for astronomy

"Galaxies and nebula" are faint and spread out, and for that very little matters as much as aperture! Back before light pollution was a a serious problem, 6 inches (150 mm) was generally acceptable, ...
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  • 443
3 votes

How does diffraction occur in a reflecting telescope?

Diffraction has nothing to do with whether you are using a lens or a mirror in your telescope. Diffraction occurs for the same reason in reflecting telescopes as it does in refracting telescopes: it ...
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  • 16.8k
3 votes

Improving portability of truss Newtonian

I have two options, but the experts might not like them. The first is to replace the carbon fiber poles with telescopic tubing similar to that used for camera tripods, but maybe a bit more robust. The ...
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  • 1,499
3 votes

Is there any specific way to record observations on any celestial object while looking through a telescope?

There are several observational astronomy tasks that have traditionally had active amateur participation. The important things to note will vary depending on the task, but will include the precise ...
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