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Interesting birding articles.

How to choose binoculars most suitable for your needs

This article has been written to help you learn how to evaluate binoculars and then show you how to choose binoculars based on your budget and the purpose for which you plan to use them.

We shall be looking at how binoculars work. Understanding this will help you to understand the different factors that will affect price and the features that are available - usually these revolve around optical quality, magnification power, and portability – before moving on to look at different price categories and justifications for buying a more expensive pair depending on what they will be used for.

The overall aim is to prepare you for the task of finding the right pair of binoculars, at the right price, without compromising on features that you may require.

How Binoculars Work

Essentially, all binoculars are derived from classical telescopes, which consist, in their most basic fashion, of two lenses. The lens nearest whatever is under scrutiny (objective lens) provides an image, which can then be enlarged by the lens nearest the viewers eye (eyepiece lens), by moving it closer or further away from the objective lens.

A pair of binoculars can be seen as two such telescopes, side by side, which together produce an image which has the depth of field that we are used to, rather than just a large flat image.

Since the light has been refracted (bent) as it has been directed through the lenses, by the time the viewer sees the image it is back to front, and upside-down. To correct this, two prisms are placed inside the binoculars, between the objective and the eyepiece. It is the presence of these four prisms in the shoulders of the binoculars that give them their squat appearance.

Power, Light and Weight

The power of the optics is expressed as two numbers, such as 7 x 35. The first is the number of times magnification, and the second is the diameter of the objective lens. A larger objective lens makes sense during low light conditions, since it can capture more of the available light.

The magnification factor tells you how many times larger the object will be magnified – a number of between 4 and 7 is ample for most applications. Any larger than about 9 or 10, and the natural shake of the human hand will be magnified to such an extent that the image becomes difficult to see, and a tripod will be required.

Glass also has a tendency to reflect as much as 5% of the light that arrives at its surface back towards the light source. A simple coating was devised to prevent this, by allowing more light to pass through the lens, and less to be reflected back. Since the advent of the original coating, the technique has been refined, and there are several grades of lens coating available.

The best result is achieved when multiple layers of coatings are applied, to the front and rear of the lens. Each coating is designed to provide the maximum transmission of light through the lens, and minimum reflection and diffraction, resulting in a brighter, clearer picture than with standard non-coated lens models.

Modern lightweight binoculars have also evolved in terms of the use of roof prisms, rather than the traditional Porro prisms. This means that they have no ‘shoulders’ and look more modern. The lack of superfluous casing makes them easy to carry, and substantially lighter than traditional binoculars, however the price tag for higher power models tends also to be more substantial than for the traditional type of a similar magnification.

Pricing Justification

When considering how to choose binoculars price is a major consideration. There are several factors that will affect the price. The first is the type of lens and coating that is used; glass lenses, which are coated on each side with multiple layers, will produce a picture at high magnification which is substantially clearer and brighter than that produced by plastic lenses.

Plastic lenses, on the other hand, tend to make the binoculars lighter, but will be substantially more expensive for the same grade of picture quality. If the binoculars are to be used in clear conditions, at a low power, then this may be acceptable. If more variation in lighting (i.e. dusk and night use) is expected, then one should opt for better quality optics, and hence a higher price tag.

The build quality will also affect the price. More rugged, shock-proof binoculars destined for use in harsher conditions (marine or backpacking) will cost more than those which do not need to be waterproof or shockproof.

Uses and Solutions

Before you decide how to choose binoculars you need to consider the solutions for differing environments. Single scopes or spotting scopes, for example, are often used for hunting. Here, since they are, in effect, half the size of a regular pair of field glasses, better quality optics can be afforded, as the cost will be proportionally lower.

Hunting glasses need to be good in all light conditions, from dawn to dusk, and even have limited night vision. In general they should be lightweight, but probably with a smaller magnification, and larger objective.

High power spotting scopes, or binoculars, where the power exceeds 10x will need to be mounted on a tripod. The best models will be ones with a very large objective lens, suitable for use in many conditions, but will be too heavy and cumbersome for use on the move.

Finally, if you are going to do hiking while hunting, it is important to note that optics are very fragile, and so plastic lenses over glass ones, and a rugged case are probably going to be more important than high power, or the ability to use them at night.

As a curio, it is possible to buy, from Zeiss, a pair of binoculars which have a mechanical anti-jog mechanism which allows for extremely high magnification, but without the shake associated with it. They come in at around $4000.

Digital binoculars are a cheap alternative, and can be picked up for considerably less ($200), and usually have a built-in camera. They are not perfect optically, with a resolution of around 3 mega pixels, but will suffice for the hobbyist.

Jargon Explained

There are many different terms that are bandied about when reading descriptions of binoculars and before rushing off to the store, it is worth understanding some of the more esoteric ones.

For example, there are several different descriptions of the coating that has been used (see Power, Light and Weight) to reduce the amount of light reflected back through the lenses during magnification:

C : Some surfaces coated
FC : All surfaces coated, except plastic lenses
MC : Some surfaces have been coated in multiple layers
FMC : All glass surfaces are coated with multiple layers.

In the last case, one would expect a good quality piece of optics to be able to transmit between 92% and 95% of all available light back to the eye.

The “Exit Pupil” is also important and can be calculated by dividing the power by the objective size and yields a value which is very important – it is the diameter of the light fed to the eye. Given that the average human pupil ranges in size from 2mm to 7mm depending on the available quantity of light, it is clear that, in the midday sun, an Exit Pupil value of 4mm (for example) will mean that 50% of the image returned to the eye is lost.

By a similar token, if the value is smaller than 7mm for a night scope, then it is not taking advantage of the human anatomy. A word of advice – always use night scopes in the dark, to keep the pupil as wide as possible; this means no, or very low, light around the place that you choose to hide out whilst communing with nature.

Finally, if the phrase ‘Eye Relief’ is mentioned, then it refers to the way that the eyepiece is set up with respect to the other optics in the device. Most glasses will come with eye relief between 9mm and 13mm, and is the distance from your eye to the lens before your field of view becomes limited.

If you wear eyeglasses, then eye relief above 14mm becomes desirable, since you will already have a certain amount of distance between your eye and your eyeglass lens, which you can not change. Given this, if your chosen optical device has a small eye relief, then you will have a very restricted field of view, and miss out on most of the picture!

As you can see when you need to decide how to choose binoculars most suitable for you there are many aspects to consider. Hopefully this article will have made your job easier. For more information on the binoculars available you can visit the relevant links.

Guy Lecky Thompson is a successful freelance writer offering guidance and suggestions for consumers regarding binoculars, telescopes, rifle scopes, laser sights, night vision, spotting scopes, night vision goggles and binocular. His many articles give information and tips to help people save money and make smarter decisions.

The advantages of the spotting scope over binoculars

For an avid birder, his outdoor equipment can make the difference between a hit and a miss; a breathtakingly beautiful sight or a missed golden moment that can never be recreated! Small wonder then that spotting scopes are fast gaining popularity among regular outdoors enthusiasts. The spotting scope is a compact telescope designed largely for terrestrial observing and is used in applications that involve magnifications beyond the range of a typical binocular. Compact and powerful, these optical instruments ensure that you are spot on - always!

There are many instances when a pair of usual 7x to 10x binoculars can be inadequate either because of lack of magnification or clarity. This is where a spotting scope comes in handy. Spotting scopes offer more magnification than binoculars and can help you locate targets at extreme distances that can be missed by observers with binoculars. Generally sold with zoom type eyepieces in either 15-45x or 20-60x magnifications and used with a tripod for stability, these will allow you to identify or observe birds at distances beyond the reach of your binoculars.

Uses of spotting scopes

Spotting scopes are perfectly suited for activities like long distance bird watching and nature study, telephotography, hunting, scenic observing, long distance microscopy, beginning astronomy and surveillance. Depending on the type and design of the spotting scope, the magnification can range from about 10X to 250X, using either fixed or zoom eyepieces. Whether you use it to identify a trophy buck at long range, observe migrating crane in the winters or spot bullet groups at the range, a spotting scope will augment your pleasure in the outdoors.

Types of spotting scopes

In addition to magnification, spotting scopes can also vary depending upon their design. There are two basic body designs – straight and angled. With straight scopes, the barrel and the eyepiece are parallel, while in angled scopes the eyepiece is 45º from the barrel axis so as to bend the light path. Each design has its own pros and cons and the choice of scope boils down to how you want to use it. Here are the advantages of each design:

Angled Spotting Scope

Easier to share with a group

Higher eye point means you can use a shorter tripod

Better for spotting soaring or nestled birds.

Straight Spotting Scope

Easier to aim for beginners

Easier for viewing birds on the ground or water or below a cliff

Less strain on your neck for level viewing

Advantages of using spotting scopes

Though there are many advantages of spotting scopes over binoculars, one of the primary one is that a scope allows you to observe sensitive species such as cranes and eagles from friendly distances. As more and more people take to the field, it is becoming increasingly important to watch in ways that are minimally disruptive and stressful to wildlife. The magnification of spotting scopes allows you to do that and makes scopes ideal for any nature activity in wild!

Finding a bird in a large flock

Imagine locating a Curlew Sandpiper just coming into breeding plumage among thousands of birds in the wild or the Spotted Redshank nestled among thousands of Yellowlegs, Dowitchers, and other shorebirds! Finding it using binoculars is can be a trying task, and there’s no guarantee that you might finally be able to see it at all. But with a spotting scope, simply by virtue of its higher magnification, you can easily spot the elusive bird. Chasing rarities with these scopes is a pleasure!

Locate a bird in its hiding place

Some birds visit certain places only for a few hours or days in a year and are often on the move. Never staying still they are constantly pushing ardent bird watchers to the edge. Equipped with spotting scopes, you can spot a movement on the ground or air, from even as far as 200-300 yards away, and capture that mysterious bird in your scope, before it flies away, never to be seen for a long time.

Distinguish between similar species

The simplest way to spot different species of birds in the wild is by some color distinctions. However on a dark, overcast day, when the colors are nonexistent, poor lighting means that you will be not be able to spot the differences without close proximity. A spotting scope with its clarity and magnification can make this assignment successful and memorable. You can observe the birds without getting too close to scare them away!

Identifying look-alike birds

Distinguishing between look-alike birds can be a daunting task, especially for newer birders. Sometimes different species have such similar coloration and patterns that’s it is absolutely essential to zoom to the closest possible frame to make the distinction. And once again, spotting scopes have a definite edge over binoculars. With unbelievable clarity, scopes offer much better results than binoculars!

In other words, spotting scopes can help you spot a bird in a large flock, trace where it is hiding, spot distant birds, distinguish between similar species, and identify look-alike birds. In addition, spotting scopes can also be used for recording images and not just plain viewing. One of the most popular uses of spotting scopes in addition to spotting is telephotography.

Telephotography

We all love bright, high-contrast images with true-to-life colors. To capture your sightings for years, nowadays most models of spotting scopes offer the capability to use the spotting scope lens as a telephoto lens. The optical design and configuration of the scope and the available accessories determine its performance and effectiveness for this purpose. As opposed to a camera telephoto lens, spotting scopes usually operate at much higher magnifications and at a fixed aperture or f/number, and need more stability and a higher speed film plus slower shutter speed options for correct exposure.

Digiscoping

Imagine capturing wildlife in its purest form, and being able to save it for later viewing! Now you can - digiscoping is here. Defined as a spotting scope with a digital imaging system, this remarkable spotting scope has a built-in imaging system and optical beam splitter for simultaneous visual and electronic monitoring. All images are output to a standard RGB signal that lets you view images on a TV, camcorder, computer, LCD viewing screen or a digital camera in amazing detail. Simply put, digiscoping is perfect for recording list birds or tracking the trophy elk you've been pursuing for years.

Though spotting scopes have many advantages over binoculars, yet some birders avoid spotting scopes because they find these more complex to use than binoculars. Scopes do offer a higher magnification but at the cost of the field of view. Plus, the discomfort of one-eyed observing can make them a little difficult to use at first. But with a little practice all these obstacles can be mastered. Any birder who can use binoculars can learn to use a spotting scope and trust us, the views will be worth it!

TIP: Generally, the best way to use a spotting scope while birding is as a back up to your binoculars. Use the binoculars to find the bird, and the scope to identify what you've found but cant make out clearly. Try not to use your scope as your primary glassing tool since this may tire you out too soon, especially if you are a novice. Remember when using your scope, it's much easier to initially find things in the image by turning the power down to its lowest point and using the widest possible field of view.

Picking the right spotting scope

A spotting scope is a sure way to open new birding opportunities for you. Whether you observe in the great wide open or locally at your city park, a spotting scope will add a new dimension to your birding. If you anticipate any field use of the scope, investing in a waterproof scope would save you a lot of hassle. Hardcore birders also appreciate strong construction and preferably nitrogen filled optics so they won't fog up.

Plus, always remember that usability is equally important in spotting scopes. A good birding scope should live up to the elements but it shouldn't be too heavy to carry. Furthermore, it should be easy to focus and usable on a car window mount, for those times when you dare not step out of the vehicle and disturb the natural world. Built-in, slide-out sunshades and easy-to-use lens caps will also help a lot. Last but not least, a good scope needs a good tripod to help you keep steady.

There is no doubt that with spotting scopes, magnifying is perfected. Spotting scopes have mastered the task of bringing distant objects closer and even storing them as photographs or digital images. Not only do they range widely in capability and price, but also offer more steadiness and clarity than a binocular with the style of a telescope. Here’s wishing you lots of amazing and extraordinary sightings with yours!

Garima Sharma is a successful freelance writer offering guidance and suggestions for consumers regarding binoculars, telescopes, night vision, spotting scopes, night vision goggles and binocular. Her many articles give information and tips to help people save money and make smarter decisions.

How do Night Vision Devices Work?

This article is aimed at helping you understand night vision devices. By understanding the different types of scopes including passive starlight, active starlight, active infrared, image intensifier along with combination systems and the principles involved, you should feel confident when it comes to purchasing a night vision device – be it for recreation, sport or surveillance purposes.

In the course of the article we shall see how each kind of night vision device works, and evaluate its’ effectiveness under a variety of lighting and weather conditions. Understanding the general principles will enable the reader to choose between different price and operational categories of device so that they can make an informed decision on budget and convenience.

One of the deciding factors when choosing night vision devices is knowing whether it will be used predominately in slight darkness, low light situations, or complete dark, where there is no light source whatsoever. As we shall see, there are devices to suit each of these situations, and knowing how they work will help make the right decision.

The overall aim is to empower the reader with the knowledge that they need to judge which of the available devices is appropriate in terms of proposed usage conditions and budget.

How Night Vision Devices Work

Without going into too much scientific detail, the basic principle of night vision devices is that incoming photons strike a photoelectric plate. A photoelectric plate is one which reacts to being struck by photons by releasing a number of charged particles, electrons, for each photon that strikes it.

These electrons are then accelerated through a photomultiplier, which produces even more electrons by using a very high voltage to propel them down a tube. The electrons then strike a phosphor screen, which reacts to them by creating pools of light which is visible to the human eye.

While the above is reasonably accurate, it is necessarily a slight simplification of the processes involved. The most important point to remember is that the most common devices merely amplify the existing light. Consequently, the image is slightly blurry and low resolution, but perfectly adequate for many low level hunting applications.

There are several generations of device, each using slightly different principles to achieve the same result (with differing degrees of success). Some are more technologically advanced than others, and consequently come with different price tags attached to them.

So called second generation devices work by taking the electrons and forcing them through a device known as a micro channel plate (MCP) which multiples them, and produces a much larger stream of electrons which are then propelled towards the phosphor screen as before.

The result is a better image, which is somewhat less fuzzy, and can be viewed whilst moving in reasonable conditions. They also cost about $1,000 more, but well worth it for the hardened night hunter.

There are also third and fourth generation models used in military and police environments which use chemical layers over the phosphor screen to achieve a brighter image with better contrast.

All of the above rely on some light to work effectively – unlike passive scopes, however, they only need a very small amount of light, and can amplify it by up to a thousand times. They will still not work in complete darkness, however, but this is a very rare situation to be in.

For operation in complete darkness, or in cases where extremely high image clarity is a requirement (emergency, police, military and surveillance), an infra red augmented device will be needed.

Passive Starlight Scopes

The simplest, and cheapest form of night vision devices, sometimes referred to as starlight or passive night vision scopes use an abnormally large objective lens. The more expensive versions use one which is also coated in multiple layers of a special chemical which allows them to transmit up to 95% of the light back towards the viewer.

These work by capturing whatever light is available, be it moonlight, low level sunlight, or even a streetlamp (for urban surveillance), and condensing it to a smaller area, which has the effect of pushing up the number of photons per square millimeter. The net result is a brighter image which the human viewer can resolve into a picture of the night.

These are the least effective, and are of no use at all in real night, where there is no light available at all. So, for night time surveillance or hunting, you will need a pair of true night vision goggles, binoculars, or scopes.

On the other hand, as a solution for use in low light (dusk, moonlight, dawn and so forth) they do offer a good compromise and have the advantage of being purely mechanical, with no electronics to require power or malfunction. They are also silent in operation and extremely portable, making them good for early morning or evening nature watching.

Some passive starlight scopes are now fitted with infra red projectors which illuminate the target with an almost invisible light source, which catches the reflected infra red light, and allows the viewer to ‘see’ in the dark. These are good for a cheap, effective, close proximity solution for viewing wildlife at night. Humans can just about see the illumination, however, making them impractical for surveillance.

Active Starlight Scopes

Active starlight scopes work on the principle that there is some light available, and they magnify it such that the image is clearer than if it were viewed with the naked eye. They do, of course, need to be powered. Anything that needs power becomes slightly less practical if you are going out into the great outdoors. So, the first rule is that if you are going somewhere where power outlets are not guaranteed, then a battery powered version will be needed.

Active Infra Red Scopes

The basic premise of an active infra red night vision scope is that it intensifies available infra red light which is out of the human viewing range, but which is exuded by almost everything that surrounds us at night. The key operating principle is that the device needs to take this light and convert it, as easily as possible into something visible.

Operation is similar to a regular active scope, with the exception that the infra red night vision device is able to pick up streams of infra red wavelength photons, rather than regular light, and convert them into a phosphor image. The additional technology required makes them more expensive, but they do offer the ability to be able to see in absolute darkness.

Image Intensifiers

Image intensifiers use a combination of all available light sources, visible and not to produce excellent, natural results, but are at the top end of the price range, and usually only possessed by the military.

Combination Systems

With the advent of computers it is also possible to purchase purely electronic image intensifiers and night vision systems, such as those in modern video cameras. These work by using a combination of low light and infra red, which is then enhanced electronically to produce an acceptable image for filming.

As a consumer product this approach is satisfactory, however for true wildlife photography in the dark, a much better quality, and hence purely optical, solution is necessary. Video cameras are also quite noisy and likely to scare of the subject – no good for hunting, surveillance or nocturnal bird watching.

As you can see there are many aspects to consider before coming to a decision about which of the night vision devices is best for you. Hopefully this article will have made your job easier. For more information on the night vision equipment available you can visit the relevant links.

Guy Lecky Thompson is a successful freelance writer offering guidance and suggestions for consumers regarding binoculars, telescopes, rifle scopes, laser sights, night vision, spotting scopes, night vision goggles and binocular. His many articles give information and tips to help people save money and make smarter decisions.

Understanding the telescope and choosing the best one for you

Purchasing a new telescope can be baffling, especially for the first timer. And most of us are left wondering, which one of the telescope range would be best for me? Understanding telescopes and their various accessories can go a long way in choosing the best one for you. Whether you are an amateur astronomer or veteran pathfinder, here are a few basic principals that will help you understand and better identify the different types of telescopes and help you opt for the telescope most suited to your needs.

Aperture of a telescope

A most important attribute of the telescope is its aperture, which determines the brightness and sharpness of everything you see through your scope. Technically, this is the diameter of the main lens or mirror and as the aperture increases so does the details of the image you see. Depending on the aperture you will either see an open or a restricted field of view. For example a good 10" aperture scope shows sharper images than even a well-made 6" aperture telescope.

But since aperture is so important, it is easy to be misled into believing that getting the biggest aperture you can afford is the simplest way to choosing the telescope best for you. However in practice it's not so straightforward. If you make your decision based solely on the size of aperture, you might end up owning a massive telescope that sits in a corner gathering dust.

Ask yourself, where will I want to use my new telescope? If the answer is nearby in the backyard then having a large telescope will be of advantage to you. If you need to carry the telescope to darker skies away from city lights, you will definitely need something compact, yet powerful. And don’t forget that you will have to assemble and set up your telescope in the dark making it even more difficult. And a scope that is too huge to carry outdoors and too long-drawn-out to set up, will rarely be of use.

Power or Magnification of the telescope

Keeping aperture in mind, consider other important aspects like power and design before you make up your mind about the telescope you would like to purchase. Power is the magnification that the telescope can offer. This is a critical factor since it decides how close a view you can get of the space and planets. But it is not a decision making factor. You can make any telescope magnify at effectively any power you want by using different eyepieces.

An eyepiece is the small removable lens assembly you look into. Most telescopes come with several eyepieces and you can buy more separately. Remember to match the power of your eyepiece lens with the aperture of your scope for clear images. Using a very high power lens with a small-aperture telescope will show a highly magnified fuzz while with a large-aperture scope can show a meaningful image even at 200x or more. In either case, the lowest powers are the easiest to use, especially for beginners, and provide the most pleasant views.

Three basic designs of telescopes

Even among telescopes with the same aperture, some designs are more portable, others give sharper images while still others are more economical. There are three basic kinds of telescope to choose from depending on your specific requirements

Reflecting telescope,

Refracting telescope, and

Catadioptric telescope.



All these 3 telescopes have the same light-gathering properties, despite their differences in size and weight. They also have a similar purpose, to collect light and bring it to a point of focus so it can be magnified and examined with an eyepiece, but each does it differently. Consequently, each type of telescope has its pros and cons, which you can match with your observing needs.

The refracting telescope or refractor

Refractors are the most common form of the telescope - a long, thin tube where light passes in a straight line from the front objective lens directly to the eyepiece at the opposite end of the tube.

Advantages

Easy to use and consistent due to the simplicity of design.

Good for distant terrestrial viewing

Excellent for lunar, planetary and binary stargazing especially with larger apertures

Sealed tube protects optics and reduces image degrading air currents

Rugged, need little or no maintenance

Disadvantages

Generally have small apertures, typically 3 to 5 inches

Less suited for viewing small and faint deep sky objects such as distant galaxies and nebulae

Heavier, longer and bulkier than equivalent aperture reflectors and catadioptrics

Limited practical usefulness

Good-quality refractors cost more per inch of aperture than any other kind of telescope.

The reflecting telescope or reflector
Reflectors use a huge concave parabolic mirror instead of a lens to gather and focus the light to a flat secondary mirror that in turn reflects the image out of an opening at the side of the main tube. You look through an eyepiece on the side of the tube up near the top.

Advantages

Easy to use and even construct

Excellent for faint deep sky objects such as remote galaxies, nebulae and star clusters because of their larger apertures for light gathering.

Low in optical irregularities and deliver very bright images

Reasonably compact and portable

A reflector costs the least per inch of aperture compared to refractors and catadioptrics since mirrors can be produced at less cost than lenses

Disadvantages

Generally, not suited for terrestrial applications

Slight light loss due to secondary obstruction when compared with refractors

The tube is open to the air, which means dust on the optics even if the tube is kept under wraps

Reflectors may require a little more care and maintenance

Catadioptric telescope

Catadioptrics use a combination of mirrors and lenses to fold the optics and form an image. Catadioptrics are the most popular type of instrument, with the most modern design, marketed throughout the world in 3 ½” and larger apertures. There are two popular designs, the Schmidt-Cassegrain and the Maksutov-Cassegrain.

In the Schmidt-Cassegrain, light enters through a thin aspheric Schmidt correcting lens, then strikes the spherical primary mirror and is reflected back up the tube to be intercepted by a small secondary mirror. The mirror then reflects the light out an opening in the rear of the instrument where the image is formed at the eyepiece.

Advantages

Most versatile type of telescope

Best near focus capability of any type telescope

First-rate for deep sky observing or astrophotography with fast films or CCD's

Excellent for lunar, planetary and binary star observing plus terrestrial viewing and photography

Closed tube design reduces image degrading air currents

Compact and durable

Disadvantages

More expensive than reflectors of equal aperture

Its appearance may not be suited to everybody’s taste

Slight light loss due to secondary mirror obstruction compared to refractors

The Maksutov-Cassegrain telescope design has basically the same advantages and disadvantages as the Schmidt. It uses a thick meniscus-correcting lens with a strong curvature and a secondary mirror that is usually an aluminized spot on the corrector. The Maksutov secondary mirror is typically smaller than the Schmidt's giving it slightly better resolution for planetary observing.

However, the Maksutov is heavier than the Schmidt and because of the thick correcting lens, it takes a long time to reach thermal stability at night in larger apertures. The Maksutov optical design typically is easier to make but requires more material for the corrector lens than the Schmidt Cassegrain.

Telescope mountings

Now that you have learnt about aperture, power and the different types of telescopes, let us discuss an often overlooked but very important aspect of using a telescope – the mountings. Remember that shaky view is all it takes to kill your enthusiasm! And a good mount can enhance your views. There are two basic telescope mountings:

The equatorial and The altazimuth.

An Equatorial mount is designed so you can easily track the motion of the sky as the Earth turns and its motions indicate celestial north south and east west in the eyepiece. This is a great help when you're trying to find your way among the stars with a map. The Altazimuth mounts are simpler and just swing up, down, left and right. You have to move the scope along every so often to follow the stars, moons and planets. An altazimuth mount is both cheaper and lighter for the same degree of stability, advantages that are offered by an equatorial mount design.

You and your telescope

Whichever telescope you pick, choose one that will meet your precise needs and hobbies. The planets, the Moon, and close stars require high power, good contrast, and sharp resolution, and if these are the objects of your attention, a refractor or reflector is probably the best bet. While very faint objects like galaxies and nebulae need a huge aperture and you should invest in a big reflector telescope to view these. And if you haven't specialized, an all-purpose midrange telescope should serve best, for example a 6” or 8” reflector or an 8" Schmidt-Cassegrain.

Garima Sharma is a successful freelance writer offering guidance and suggestions for consumers regarding binoculars, telescopes, night vision, spotting scopes, night vision goggles and binocular. Her many articles give information and tips to help people save money and make smarter decisions.