Are Telescope Images Real or Virtual?

Yes, telescopes can produce both real and virtual images. The type of image produced by a telescope depends on the type of telescope and the configuration of its optical components.Refracting telescopes, which use lenses, typically produce real images because the final image is formed by the convergence of actual light rays at the focal plane….

Hot to call a telescope building? (Observatory)

An observatory is a telescope building that provides a permanent and secure space for a telescope to be used for long-term astronomical observations and research. They are typically designed with features such as a dome that can be opened and closed to protect the telescope and control the amount of light entering the viewing area….

Are Telescope Eyepieces Universal?

Yes, most of modern telescope eyepieces are universal, however older eyepieces are not universally interchangeable. The interchangeability of telescope eyepieces depends on the telescope’s design and the focal length of the eyepiece. Telescopes that use a 1.25-inch or 2-inch diameter barrel system can accept eyepieces of those sizes. However, some telescopes, particularly older or entry-level…

How to Make a Newtonian Reflecting Telescope?

Building a Newtonian reflecting telescope is a complex process that requires careful preparation, precise construction, and thorough testing. The process involves preparing tools and materials, shaping and mounting telescope mirrors, building the telescope tube, installing a focuser, aligning telescope optics, assembling the telescope, and testing and calibrating the telescope. A DIY Newtonian reflector requires maintenance…

What to Do if You Inherited a Telescope?

If you have inherited a telescope, there are several steps you can take to determine its condition and usability. First, carefully inspect the telescope for any visible damage or wear, such as dents, scratches, or misalignments in the components. Check the optics, such as the lenses or mirrors, for any cracks or chips. Next, assess…

What Telescope to See the Planets?

For planet viewing, refractor telescopes are the best telescopes for beginners because they have excellent contrast and resolution for viewing the Moon and planets up close. They are also the easiest telescope type to use and require the least maintenance. However, for more advanced planet viewing, especially if you are interested in astrophotography, you will…

How Fast is Your Telescope?

An explanation of the f/ratio of telescopes The f ratio of telescopes is very important. It makes a difference in the size of a telescope and the viewing that can be done with it. In this article I explain what the f ratio of a telescope is all about. And telescopes are designed with a…

The Biggest Telescopes in the World

  The Telescope turns 400 years old this year and in four century period astronomers and telescope makers have been continually making larger and larger telescopes in order to peer deeper and deeper into the mysteries of the universe. There are currently quite a few enormous instruments in use and there are several next generation…

Looking to Buy a Dobsonian?

Thinking about buying a dobsonian? It’s a big decision and one that’s not made lightly. I have laid out a lot of information here that will help you. -The Telescope Nerd If you are considering the purchase of a Dobsonian telescope you are making a great decision. This type of telescope offers you remarkable light…

Barlow Lens For A Telescope: Usage and Function

The Barlow eyepiece, commonly referred to as the Barlow lens, is a part of the telescope assembly designed to enhance the magnifying power of the primary eyepiece of a telescope. Knowing the function and application of a Barlow lens is essential to optimizing the detail and magnification observations. The Barlow lens’s primary purpose is to…

Telescope Optical Tube Assembly (OTA) Guide

The Optical Tube Assembly (OTA), also called the optical tube, is a part of the telescope that houses the optical components, such as the primary and secondary mirrors. Knowing the design and function of the OTA is crucial as it determines the operational capabilities, resolution, and sensitivity. The primary function of the optical tube assembly…

Telescope Focuser Guide: Types and Specifics

A telescope focuser is a part of the telescope that adjusts the eyepiece’s distance from the primary optical component to ensure sharp images. Knowing which type of focuser to use allows astronomers to improve the precision and clarity of an image. The primary function of the focuser is to adjust the position of the eyepiece…

Finderscope For Telescope: Alignment and Types

The finderscope is a part of a telescope that helps locate and center celestial objects in the primary telescope. Knowing the design and function of a finderscope allows astronomers to accurately and efficiently locate celestial objects.  The finderscope is a secondary telescope mounted atop the Optical Tube Assembly (OTA), designed specifically to help astronomers locate…

Telescope Filters Guide: Types, Colors, Usage

A telescope filter is a part of a telescope that modifies wavelengths of light to enhance the visibility of celestial objects. Telescope filters function by selectively transmitting certain wavelengths of light. This selectivity enhances contrast and detail while protecting the eyes from excessively bright objects. Knowing which telescope filter to use for a specific observation…

Observatories and Astronomy club visits

Trips to Observatories and Astronomy Clubs These are part of my bucket list! Things have opened up in my life in the past few years and I have made a conscious effort to visit as many observatories, telescope clubs and events as I possibly can. So here is the list and you might want to…

Catadioptric Telescope: Design, Diagram, Advantages

A catadioptric telescope, or compound telescope, is a type of telescope that combines the principles of both reflection and refraction by using mirrors and lenses. Knowing how the mirrors and lenses work together is crucial to taking advantage of the full potential of catadioptric telescopes. A catadioptric telescope captures and focuses light from distant objects…

The Make a Telescope Project

Follow along as I make a reflector telescope- And learn how to do it yourself This is the beginning of my new project where I make a telescope. I have ordered an eight inch primary mirror off ebay. It was a great deal on a brand new mirror and I will be building a telescope…

Astronomia Nova

By Johannes Kepler The Astronomia Nova is a book written by Johannes Kepler and it was first published in 1609. It is often considered to be one of the greatest books on astronomy ever published and Kepler wrote it based on his observations of the motion of the planet Mars over the course of ten…

About the First Telescope

The first documented telescope was created in the Netherlands in 1608, when Hans Lippershey, an eyeglass maker, filed for the first patent for this optical device. While it wasn’t initially invented for astronomy, this design opened the door to an entirely new field of study. When Was the First Telescope Invented? The first telescope was…

McDonald Observatory: One of the largest telescopes in the world

The McDonald Observatory, otherwise known as the Hobby-Eberly Telescope, is located in Fort Worth, Texas, in the United States. During my trip around the United States, I spent a day visiting the observatory and it had a lot of events and scheduled things to do. From tours to other events, it seems like there is…

Is that an airplane or a meteor in your night sky photo?

I take a lot of photographs of the night sky. These photos are usually less than 30 seconds in exposure length. But sometimes I catch a meteor! But, I also get airplanes in my photographs. So, how do you tell the difference? I managed to get this one photograph that has both a meteor and…

A Trip to Lowell Observatory

I took a trip to Arizona specifically to see the Grand Canyon. But while doing my research on what else to see in the state I realized that I could also visit this wonderful observatory with a long history (Which includes the discovery of Pluto). It is right inside Flagstaff Arizona which is only an…

Make the telescope part 7 : The mount

How to make a reflector Telescope Part 7: Making the mount for the telescope We finish off the telescope project by making a mount that the scope sits on We have finished the optical tube assembly and the telescope is great. It works terrific. But, we can’t just hold it and view the stars! We…

What Can an 8-inch Telescope See? (15 Celestial Objects)

An 8-inch telescope is an excellent option for those looking for an affordable spy glass that can see some impressive details. This binoculars can provide stunning views. This type of spy glass can see a lot. It can see objects up to 2,000 times fainter than the human eye. This makes it perfect for viewing faint objects…

How To Buy A Telescope

Are you interested in astronomy? Do you want to view the stars and planets up close? If so, then you need to buy a telescope. Telescopes allow you to see things that are far away in incredible detail. We will teach you how to buy a perfect telescope for your needs. We will discuss the different types…

Articles about Telescopes and Astronomy

Telescope Buying Guides Astronomers and Their Telescopes About Telescopes and Accessories How to do astronomy and use telescopes More Telescope and Astronomy Stuff Specific Telescopes and Manufacturers Information Telescope Making Articles Famous Astronomers and Telescope Makers

Magnification, eyepieces, and telescopes

Often times you will see telescopes for sale that claim big magnifications such as up to 1000X power or 500X power telescope. And while this isn’t a false claim because the telescope in reference will actually go to that magnification it is a worthless number because telescopes have definite limits to their magnification. Need the…

Hubble Telescope Stuff and Posters

Beautiful Hubble Telescope Posters and Pictures The Hubble Telescope has changed the way we view the universe. It has seen and photographed things never before seen and in beautiful color richness that is just spellbinding. You can own some of the wonderful images that the Hubble has brought to us. There is a playlist on…

Telescopes for Beginners

Choosing a telescope can be a difficult thing but the nerd will help Being a beginner in astronomy is about the same as being a beginner in just about everything else. You don’t yet even know what you don’t know. This problem is magnified by the fact that you probalby want to buy a telescope…

The Phases of the Moon

Resources to finding the current Moon Phase The Current Lunar Phase: You can put the google gadget of the moon phase right on your desktop. This handy little gadget automatically updates so it always shows you the current phase of the moon. Kind of nice. Softpedia Google Desktop for the MoonPhase. If you are in the…

Meteor Showers for 2010

Table of meteor showers for 2010 Meteor showers can be a bit hit or miss and in some years a regular shower can be fantastic and other years it can be quite slow. There are actually quite a few more legitimate showers than I have but for the most part they are irregular and slow….

Astronomy Books for Beginners

There are probably over 1,000 astronomy books readily available for you to buy and if you have been looking around you are no doubt wondering which ones are good? Well, I am going to give you three recommendations on astronomy books that are specially aimed at beginners and are easy to read and use. And…

How to take Star Photos and Star Trails without a Telescope

The picture below shows a picture I took of the constellation Sagittarius. The bright object is Jupiter. This was done with a 30 second exposure and 800 speed 35 mm film. At The Bottom of this page I have a video Tutorial of this if you prefer to watch a video. Some basic tips for…

How to take moon photos with a telescope and DSLR camera

How to take Moon Pictures with a DSLR and a telescope (How to connect your digital camera to a telescope) This is a first tutorial – There is a whole lot more you can do with this but we will start by talking about how easy it is to take pictures of the moon using…

Great Astronomers and Their Contributions & Telescopes

The Telescope has a four hundred year history and in this time there have been a lot of astronomers and telescope makers who have built telescopes, made discoveries and advanced astronomy in remarkable ways. These links are to articles written on this website about many of these famous people. This is a list that is…

Celestron Telescopes

One of the most respected manufacturers of telescopes If you are looking for quality and a company with a very long track record of making top of the line telescopes then you are looking for a Celestron telescope. Here is a selection of some of their telescopes that you can purchase through amazon.com. They run…

Building the telescope mount

How to make a reflector Telescope Part 8: how to build the mount Now it is time for us to build the actual mount of the telescope. Not a difficult thing and we only need a few basic tools and a few basic supplies. You have quite a few different options here and for all…

When can the Constellations be seen?

The constellations can be seen any night and at any time! As long as it is night time and the skies are clear. If you are seeing stars then you are seeing constellations. The reason for this is that the complete night sky is filled with constellations. Every area of the sky, all night and…

The Observatory

Interesting things in the night sky, and how to find them The Night Sky for the Year 2019 – Here is a listing of some of the major things you can see for the year. This includes, planets, meteor showers and comets. The Moon Want to Know the Current Phase of the Moon?Here is a…

A Trip to Ladd Observatory in Providence

100 Year old refractor still in perfect condition The Ladd Observatory is part of the physics department at Brown University in Providence, RI. The observatory opened in 1891 and it houses a variety of instruments including a gorgeous 12″ refractor telescope made by John A. Brashear. They have one night a week (tuesday) open to…

Makers of Telescopes

Understanding the Manufacturers of Telescopes One of the most important things you need to consider when buying a telescope is who makes it. A telescope is an astronomical instrument. It is composed of lenses and mirrors that have to be well made in order to function adequately. Remember that you need to gather the light from stars and objects…

Best selling telescopes

I have three separate lists that all come from the official amazon number and this list is updated hourly by amazon.

The Observatory – Observing in 2019

Here is an overview of the major celestial events you can watch for in 2019 Meteor Showers: These are regular occurrences throughout the year. I have a complete listing of them here ( Meteor Showers for 2012) . There are showers every month but some are better than others. Quick definition: “Opposition” This is an astronomical term…

The Quandratids Meteor shower and the constellatin Bootes

Bootes and the Quadrantids Meteor shower Here is the constellation Bootes It is from this constellation that the Quadrantids originate from . This meteor shower can be very sharp and focused. It typically lasts only three nights from Jan 2 thru Jan 4 and it can reach peaks of up to 120 shooting stars per…

William Herschel

Herschel was a famous astronomer and telescope maker who lived from 1738 to 1822. The science and art of astronomy and telescope making owes a lot to William and his sister Caroline. He was a famous astronomer and held the title of “Kings Astronomer:” And he was the most renowned astronomer of his time. As…

Making your own observatory

Books Setting-Up a Small Observatory: From Concept to Construction (Patrick Moore’s Practical Astronomy Series) This is the book to tell the intermediate-level amateur astronomer what he needs to know about observatories. It draws on the authors practical experience and that of many other experienced amateur astronomers. It is an ideal complement to Patrick Moores More Small…

What are the biggest telescopes in the world?

The Biggest Telescopes in the World – and some not in the world I show you the currently active biggest telescopes and also preview even bigger ones that are being built right now. You know that the nerd loves telescopes! They are buckets that collect light. And the bigger the bucket the more light they…

Part 4 Installing the Focuser

How to make a Newtonian Telescope part 4: The focuser In this part we install the focuser assembly for the eyepiece I do have a video showing this whole process. You can watch that at the bottom of this page. Here is a picture of the completed assembly. This is what we are making in…

How to make a small telescope part 3

How to Make a Telescope (Part 3 Making the telescope) How to Make a Telescope: In this part of the tutorial I show you how to assemble the telescope In this part of the telescope making tutorial I show you the nuts and bolts of how to make and assemble the telescope. I also have…

How to make a Newtonian Telescope part 3

In this part we make the Mirror Mount and install the mirror into the tube I do have a video showing this whole process. You can watch that at the bottom of this page. Here is a picture of the completed assembly. This is what we are making in this part. This part is really…

How to Explore the Night Sky without a Telescope

You don’t need a telescope to see a lot of wonderful things in the night sky. For example five of the planets are often readily visible with the naked eye. There are lots of amazing things you can see and this guide will help you find them. To maximize what you can see in the…

Maksutov Cassegrain Telescope: Comparison, Advantages, Optics

The Maksutov-Cassegrain (Mak) telescope is a type of catadioptric telescope that employs both mirrors and lenses to produce an image. Its design incorporates a thick meniscus corrector lens and a spherical primary mirror, efficiently reducing optical aberrations. The Maksutov is recognized for delivering high contrast, particularly in planetary observation, and has become a preferred choice…

Cassegrain Telescope: Classical Design, Advantages, Comparison

The Cassegrain reflector is a type of telescope that uses a combination of a concave primary mirror and a convex secondary mirror to gather and refocus light, producing magnified images of distant celestial objects. Knowing the interplay between these mirrors is vital to optimizing observations with the Cassegrain design. The Cassegrain telescope’s ability to provide…

Schmidt-Cassegrain Telescope: Pros & Cons of SCT Design

The Schmidt-Cassegrain Telescope (SCT) is a compound telescope that combines mirrors and lenses to create an image. The SCT uses a spherical primary mirror, a secondary mirror, and a corrector plate to correct spherical aberration, resulting in a compact and adaptable instrument. The SCT is known for its portability and versatility among both amateur astronomers…

6 Common Types of Telescope Mounts, Tripods: Guide

A telescope mount is a part of the telescope setup that supports the Optical Tube Assembly (OTA) of a telescope. Knowing the different types of telescope mounts and tripods allows astronomers to select a design that ensures stability during sessions and optimizes the navigation of celestial objects.  Telescope mounts are essential for stability because any…

16 Telescope Brands & Manufacturers You Need To Know

Telescopes are designed, manufactured and distributed by a wide variety of companies. Each brand distinguishes itself through unique specializations, ranging from advanced technology and premium optics to affordability and user-friendliness. This diversity allows astronomers to determine the optimal telescope for a specific observation.  Knowing a specific telescope brand’s manufacturers provides observers with deep insight into…

Telescope Eyepiece Guide (Lens): Sizes, Types, Function

The eyepiece, often called the ocular lens or telescope eye lens, plays a critical role in determining magnification, field of view and overall clarity of celestial observations. The eyepiece is a part of the telescope through which an observer looks. The primary function of the eyepiece is to magnify the image rendered by the telescope’s…

Primary Mirror In Telescope (Reflecting Optics)

The primary mirror is a part of a reflecting telescope that collects and focuses light from distant objects. Knowing the design and material of a mirror is fundamental to understanding a telescope’s abilities, as the primary mirror is responsible for capturing and manipulating light to form images of distant celestial objects. The primary mirror’s primary…

Objective Lens In Telescope (Refracting Optics)

The objective lens is a part of a refracting telescope that collects and focuses light from distant objects. Knowing the design and material of an objective lens is crucial as it influences the telescope’s field of view, magnification, and overall performance. The shape of the objective lens is convex, meaning it bulges outward. This design…

8 Primary Telescope Parts: Diagram and Functions

Knowing the anatomy of a telescope is fundamental to determining the telescope types, functions and abilities. Recognizing the main parts and how they work together allows astronomers to customize their setup based on their observational goals.  ​​Telescope parts refer to the components that allow telescopes to collect, focus and magnify light for observation. Each component…

Newtonian Telescope: Diagram, Optical Design

A Newtonian telescope is a type of reflecting telescope that gathers and focuses light using mirrors. Knowing how the principles of reflection are crucial to understanding how this telescope functions. A Newtonian reflector magnifies distant objects by reflecting light off its parabolic primary mirror. The primary mirror collects light from distant objects and converges it…

Dobsonian Telescope: Diagram, Optics, Design, Mount

A Dobsonian telescope is a type of reflector telescope designed with simplicity and functionality in mind. Knowing how the Dobsonian’s unique mount operates in conjunction with its Newtonian optics is crucial for optimal observational experiences. Dobsonian telescopes, named after John Dobson, offer a cost-effective approach to large aperture telescopes, ensuring bright and sharp views of…

Reflector Telescope: Diagram and Reflecting Optical Design

A reflecting telescope, often referred to as a reflector, is a type of telescope that operates on the principle of gathering and focusing light using mirrors. Knowing the properties of reflection and how mirrors manipulate light is key to understanding the functionality of reflectors. A reflecting telescope, or reflector, magnifies distant objects by reflecting light…

Refractor Telescope: Diagram and Refracting Optical Design

A refractor, or refracting telescope, is a type of optical instrument specifically crafted to magnify distant objects by bending light through a lens. Knowing how a refractor’s lenses manipulate light is fundamental to understanding the refracting telescope’s capabilities. A refractor is defined by its lens-based system that gathers light and refracts it to a focal…

8 Different Telescope Types and Their Optical Designs

Telescopes are available in a variety of types, each tailored to specific observational needs and based on distinct optical designs. Knowing the differences in design and application allows astronomers to determine the best telescope for their observational goals. Every kind of optical telescope relies on a meticulous arrangement of optical components to capture, focus and…

Telescope Diffraction Limit: Explanation & Calculation

The diffraction limit is the highest angular resolution a telescope is able to achieve. This limit refers to the theoretical maximum if nothing besides the size of a telescope’s light-collecting area affects the quality of the images. This limit is a direct consequence of the nature of light waves. When light waves encounter an obstacle…