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Friends, you must be thinking this website “Telescopefever.com” is about telescopes then why is there a post related to Binocular? Because Binoculars are also Telescope, in simple terms binoculars are a pair of telescopes mounted side by side on a metal frame which uses a curved lens to bring the object closer to eyes and also a pair of the prism to create a high-quality image right side up (not inverted like a telescope). Guys if you are having difficulty in deciding a right Binocular for you. Don’t worry, you are at the right place. Here is a 5 step easy guide to help you choose a good Binocular for you.

1. Magnification

Magnification is the number written before x. Suppose you are going to buy a binocular ABC8x40 here ABC is brand name and 8 is the magnification. In simple words, it means the view of the object will appear to be 8 times near than the original position of the object. Let me give you an example, let’s say a bird is at the distance of 800m from you but with this 8x Binocular the bird will appear to be at the distance of 80m.

*Don’t go for magnification higher than 10x- 12x for handheld use just because it is very difficult for hands to get steady. Up to 12x is manageable but let’s say you are using 15x magnification then any small amount of movement of your hand will result in 15 times the vibration of an image. To use Binoculars of magnification beyond 10x-12x get a tripod.*

2. Objective lens diameter

Objective lens diameter plays an important role in choosing a right telescope. The objective lens is the main lens through which light enters into binoculars. Higher the objective lens diameter larger the amount of light enters into it. Results in better image quality in low light condition. It is the number written after x in the name of binoculars. Example, ABC 8×40 here 40(always in mm) is the diameter of the objective lens.

*Higher the diameter of objective lens heavier and bulkier binoculars will be. So buy it according to your need. or you can use a neck strap to compensate the weight*

 3. Lens quality and coating

Binoculars come with a glass lens as well as the plastic lens. Always prefer glass lens over plastic lens because glass lens produces better image quality than plastic lens. There is just one problem with glass lens they partly reflect some light falling on the lens or in simple words it produces glare from the object but does not worry this can be compensated with a right coating.

There are four types of coatings done:-

Coated (C): A single layer on at least one lens.
Fully-Coated (FC): A single layer on all air-to-glass surfaces.
Multi-Coated(MC): Multiple layers on at least one lens.
Fully Multi-Coated(FMC): Multiple layers on all air-to-glass surfaces.

 4. Exit pupil

If you are going to use your Binoculars at night or in low light condition then decide according to the size of the Exit pupil. It is a diameter of the image formed on the eyepiece for your pupils to see. During low light condition, a pupil of our eyes opens about 5 to 7 mm so a binocular with an exact Exit pupil between 5-7mm will be good for night viewing.

*To calculate exit pupil just divide objective lens diameter with magnification. For example,  8×40 Binoculars would have an exit pupil of 5mm.*

 5. Waterproofing

Binoculars are made to use outdoor. So some degree of waterproofing is a must. If you are willing to use your Binoculars during river rafting, boating, skiing or any other water sport then buy waterproof binoculars (WP) otherwise use water resistant binoculars for a different purpose.

 Summary

Binoculars are priced from 50$ to above 1000$. Each has their own purpose like some are good for bird watching,  some are for hunting,  some are made for stargazing, some are specialized in sports activities, marine activities and some are for traveling purpose. Before buying any binocular first think what is your primary purpose of buying it and most important what is the budget you can afford then decide.

Meade 102mm refractor telescope is made in a such a way that it can fulfill all the basic requirements of a beginners users like easy to use, lots of accessories, low price and a decent quality optics.

Here is our review of Meade instrument 102 refractor:-

Specification

Optical Design: Refractor

Aperture: 102 mm (4 in)

Focal Length: 600 mm

Focal Ratio: f/5.9

Eyepiece 1: 26 mm

Magnification 1: 23 x

Eyepiece 2: 9 mm 

Magnification 2: 66.3 x 

Eyepiece 3: 6.3mm

Magnification: 95x

Barlow lens: 2x

Mount: Alt-azimuth

Tripod: stainless steel

Accessory Tray: yes

Weight: 20.8lbs (10.75 kg)

Meade instrument telescope is a refractor (the one that uses a lens to collect the light) telescope with an aperture of 102mm, the focal length of 600mm and a focal ratio of 5.9. Perfect for getting the bright and sharp. Always remember, bigger the aperture more will be light gathering power that will eventually result in a brighter image.

The telescope comes with three different eyepiece of 26mm,9mm,6.3mm that provides a magnification up to 23x, 66.3x, 95x (magnification=focal length of telescope /size of an eyepiece).

26mm eyepiece provides a wider field of view of the sky, easy for spotting the object and 6.3mm eyepiece will provide a magnified view of that object once spotted.

Lower the size of the eyepiece, higher will be the magnification.

To further increase the magnification 2x Barlow lens is also provided in the package. 2x Barlow lens will double the magnification of any eyepiece.

Locating and observing objects get even easier thanks to red dot viewfinder and Altazimuth mount. Altazimuth mount has a panhandle with slow motion control that helps in smooth tracking of an object.

Tripod has adjustable feature, so if you want you can adjust the telescope at your comfortable height for greater comfort to your eyes and back.

Astronomical software and DVD are also included in the package as a bonus to increase your astronomical knowledge and also what and where to look for in the sky to find the celestial objects. A nice software to turn your viewing experience into an excellent experience.

Pros

Meade instrument 102mm weighs about 10kg that’s why it is easy to carry from one place to another.

Easy to Setup!!! It will not take more than 10 minutes even for novice users to set up the telescope with the help of instruction manual.

No need to collimate (aligning the mirrors) the telescope because it uses a lens to capture the light.

Due to its erect image optics, it can also be used for terrestrial viewing (like a binocular) like observing mountains, sea, boats etc.
We are getting a decent quality three eyepiece and also a Barlow lens free with the telescope which will otherwise cost extra 100$ when buying separately.

Accessories tray is also present to safely keep the eyepiece or Barlow lens.

Meade is also providing one year warranty on this telescope.

Cons

Meade 102mm refractor has a weak aluminum tripod as compared to another steel tripod that comes with high-end telescopes. But don’t worry there is a hack for that, put a heavy sandbag on the accessories tray to provide more stability to the telescope.

 Summary

Meade is offering 102mm lens, a set of 3 eyepieces, a Barlow lens and much more that no one is offering in this price range. The price cut has been done in some sections like in tripod by lowering the quality but the main telescope and its optics are not compromised. We all know Telescope is a high-end sophisticated device which is always expensive (some are above 1000$) but Meade has done a really commendable job in making a telescope that is perfect for the hobbyist or beginners who don’t want to spend too much on their first telescope.

In fact, we were so impressed with this Meade infinity 120AZ Refractor telescope that we had to include this telescope in our “The best telescope for beginners” list this year.

The 10inch Dobsonian telescope from Sky-Watcher is a Newtonian reflector telescope where the mirror is used to gather light. Designed for amateur and intermediate users, this telescope offers a large aperture, short focal length, good optical quality and great light gathering quality, all at an affordable price. In addition, its collapsible feature makes it easy to carry and move from one location to another.

Specification

Optical Design: Newtonian Reflector

Aperture: 10″ / 254 mm

Focal Length: 47″ / 1200 mm

Focal Ratio: 4.72

Eyepiece Barrel Diameter: 1.25″

Eyepiece: 25 mm-48x

Eyepiece2: 10 mm-120x

Maximum Useful Magnification: 600x

Limiting Stellar Magnitude: 14.5

Finderscope: 8×50 RA Viewfinder

Mount Type: Dobsonian

Weight: 46.2 lb / 20.97 kg

Our Rating: 4.5 out of 5

Optics

The Sky-Watcher features a 10-inch objective mirror where on each primary mirror and elliptical diagonal mirror vacuum is deposited to the front surface and then again over coated with hard quartz (SiO4). After that again additional layers of Titanium Dioxide (TiO2) and (SiO4) are applied. This high-quality chemical treatment on the mirrors yields smooth surface that results in good contrast images with minimum color distortion. In addition to bigger 10-inch aperture and high-quality optics, telescope also has a fast focal ratio of f/4.72 that makes the telescope ideal for wide field deep sky observation like galaxies, nebulae, star cluster which otherwise not possible with other smaller telescope.

In addition, Sky-Watcher has included 4-element 25mm and 10mm Plossl eyepieces that provide increased magnification and a 52° apparent field of view. Reviewers report enjoying a clear view of M8, M20, M17 nebulae, and great Orion nebulae and also the outstanding view of Andromeda galaxy, planets, and the moon.

Design

Sky watcher is using its revolutionary truss-support system, a feature that makes the telescope portable despite its large size. The system allows the optical tube’s front and back tube to collapse together easily by loosening the three knob and making it compact so that it can fit in the small car. In addition, for smooth horizontal and vertical manual movement, Sky Watcher uses a high-performance Teflon bearing system in both axes. Teflon bearings give better friction than ball bearing and also save the device from any automatic movement occurs due to small bumps or gusts of winds.

Pros

Easy to setup– Assembling the telescope is simple. Even a beginner user can assemble this 10 inch Dobsonian in less than an hour with the help of included easy to follow instruction manual without any expert.

Large aperture– Because of its large aperture and better optics Skywatcher, 12-inch Dobsonian performs extremely well in light polluted area. Reviewers report that they were able to use the telescope their backyard which otherwise was impossible for a smaller telescope because of street lights.

Collapsible– USP of this telescope is its collapsible feature, which makes the telescope easier for transportation and storage.

Viewfinder– Package includes 8×50 optical viewfinder that helps the user to search and locate desired celestial objects easily.

Solid base

Cons

Need to collimate– Like any other reflector, Sky Watcher 10 inch Dobsonian telescope is also needed to be collimated once in a while. If you are not familiar with collimation, read

The article will help you in collimating your telescope in less than 5 minutes. Lots of YouTube video tutorial are also present

Recommended Accessories

Highest useful magnification of the device is 600x, to take full advantage of this magnification we need some additional

eyepieces and a 2x Barlow lens. Here is a link to our favorite,

Kit contains 5 different eyepieces of different length, a 2x Barlow lens and up to seven different filters.

Final words

This concludes our Sky-Watcher 10 inch Dobsonian telescope review, overall a spectacular piece of equipment for its light gathering capabilities, strong optics, high-quality optics and an excellent design. A perfect telescope for any amateur astronomer who is looking to observe deep sky objects but only has a limited budget.

Orion 27191 StarBlast 6i reflector is a perfect telescope for intermediate level users who know the basic mechanics of a telescope, knows how to use a telescope, what to look for in the sky at the time of observation, familiar with the terms like aperture, magnification etc. A very good telescope for those who want to go to next level from beginners to intermediate without investing too much money.

Have some doubt? Read our full review below and decide for yourself:-

Specification

Optical design: Reflector

Aperture: 6 in (150mm)

Focal length: 750mm

Focal ratio: f/5.0

Eyepieces: Sirius Plossl 25.0mm, 10.0mm (1.25″)

Magnification: 30x, 75x

Finder scope: EZ Finder II

Focuser: 1.25″ Rack-and-pinion

Mount type: Altazimuth

Computerized compatibility: Intelliscope included

Power requirement: 9-volt battery

Length of optical tube: 28.0 in.

Weight, fully assembled: 23.5 lbs.

Our Rating: 4/5 Star.

Optics

Orion 27191 StarBlast is a 6-inch Reflector Telescope with a diffraction-limited parabolic mirror and has an Aluminum & silicon dioxide coating to produce a clearer image of the deep sky objects that are otherwise not possible to look at with our naked eyes. StarBlast 27191 has a focal length of 750mm and focal ratio of f/5.0 that produces a brighter and sharp view of deep sky objects.

StarBlast 6i Reflector comes with two high-quality Plossl eyepiece of 25mm and 10mm that gives a magnification of 30x and 75x respectively. Low power 25mm give a wide field of view whereas high power 10mm give the closer look of the object at 75X power.

Push-to Telescope

Orion calls StarBlast 6i intelligent scope because of its computerized object locator and push to navigation system. First, align the telescope by manually pointing to 2 stars shown on remote (don’t worry if you do not know the names or position of those stars take a help of star chart) after its properly aligned rest of the process is simple.

Just put the name of Nebula, Cluster, Galaxy or something else you want to locate. Remote will tell you the exact position of that object in the sky, after that push the telescope (your hands are the motor here) to move it to that position. Once the telescope is perfectly positioned computerized object locator (remote) will notify you.

Orion StarBlast 6i also has preloaded 12-tours just put the month you are in and it will tell you what to look for in the sky at that time.

You can turn the tables on the computer too – just locate anything in the sky and push a key, with the help of 14000 object database the remote will tell you what you’re looking at.

So simple and better than GoTo type telescope (my opinion). Sometimes GoTo telescope’s automatic tracking feature take the fun out of the learning whereas Push-to feature helps to learn the night sky by manually moving and locating the stars.

Pros

The 6” large aperture and powerful optics provide some great, bright views of the planets and moon (must use a moon filter) as well as deep-sky objects.

The absence of motorized tracking saves lots of power that’s why the inbuilt 9V battery can last for months.

StarBlast has a compact design and weighs about 11kg when fully assembled, pretty light for a Dobsonian. It can easily fit into the front seat of any car.

Orion is providing a one-year warranty on this telescope from the date of purchase. You can always call Orion support if there is some problem.

Cons

This telescope is difficult to assemble for a novice user. But don’t worry, I have provided a official video from Orion below that will help you on that.

Being a small Dobsonian you will need a table or something stable to put it on.

Assembling

Final words on StarBlast 6i IntelliScope.

It already got featured in the prestigious Astronomy magazine for two times in a row as the best reflector telescope of the year in its price range. What more can be said about Orion StarBlast 6i Intelliscope!!! Overall a high quality and reliable telescope that continues to impress beginners as well as expert users.

Today we are going to review one of the affordable spotting scopes that is perfect for beginners Barska 25-125×88 WP Benchmark Straight Spotting Scope. The scope is designed to give a high level of spotting pleasure to bird watchers, shooters and all another type of nature explorer. Let’s get started,

Optics

As the name suggests Barska 25-125×88 features an 88mm objective lens with fully coated optics where a single layer of coating is done on air to glass surface. Coating helps to improve light transmission inside the tube which eventually results in better image quality. In fact, the users report that scope delivers clean, clear image and a good view out to 600 yds. If you do target shooting, the scope will not disappoint you on that front also. Users report that up to 200 yards they were able to see .223/5.56/7.62/7mm caliber holes in splatter targets.

Zoom eyepiece

With decent quality optics, Barska 25-125×88 also features a variable zoom eyepiece which can give magnification from 25x to 125x. At 25x- 80x quality of the image is great with a wide field of view but after that magnification quality is not up to the mark. User reports lot of color distortion in the image after that magnification. After all, What more can we expect from a 120$ scope!!!

How to Focus?

Barska has introduced innovative Dynamic focusing system with this scope. To focus on object user need to turn the objective eyepiece. First time observers find the process of focusing through turning the objective lens quite unique and easy but seasoned user who is already familiar with focusing knob used to focus in other scopes, quite inconvenient and awkward to use. In our opinion, it depends upon user perspective what they like.

Design & Accessories

O-ring sealed and nitrogen purged construction provides a full water proof and fog proof protection while rubber armored grip gives some additional protection from external damages. Lifetime warranty from Barska is another icing on the cake, it gives the user extra confidence that they are buying a solid scope. For added protection Barska has included a soft carrying case and also the hard case in the package. A tripod and hand held accu-grip tripod are also included with BARSKA Benchmark 25-125×88 Spotting Scope for better stability to the scope.

Pros

  1. Good Optics
  2. Solid Metal Tripod
  3. A lot of free additional accessories in the package. In fact, these accessories alone cost more than 40$ when purchased separately.
  4. The scope can also be used for celestial viewing such as observing the moon.

Cons

  1. Shorter Eye Relief– Eye relief is a distance between eye piece to the eye. BARSKA 25-125×88 scope has a variable eye relief, 13mm at 25x magnification and 7.6mm at 125x magnification. Eye relief is very short, that is the reason why scope is not recommended for an eyeglass wearer.

Final Verdict

This concludes our “BARSKA Benchmark 25-125×88 Spotting Scope” review. Overall a great value for money scope that is designed to provide an extreme and comprehensive level of spotting pleasure to all type of nature explorer.

Word to the Readers

I want to request my readers to wait for one or two months if you are low on cash but never go for cheap, low-quality spotting scope that costs less than 50$. They might be cheap but the optics quality is also highly compromised (you get what you pay for, right?). They can ruin all the fun and can dramatically decrease your new found interest towards bird watching or hunting or other nature loving activities in no time. That is the reason why we never review or recommend any cheap spotting scope priced below 50$ here on.

When we are new to the field of astronomy first thing which comes to our mind is to buy a telescope, then after researching over the internet, nearest shops, from friends we encounter a lot of confusing terms like aperture, focal length, magnification, reflector, refractor etc. We get really demotivated with these terms and starts to reconsider the decision of buying the telescope. But don’t worry I am here to help you in choosing you your right telescope and removing all of your confusion with my 5 easy steps guide.

Aperture

Most important feature in deciding your telescope is aperture. It is mainly the diameter of lens or mirror used in a device which decides the amount of light to enter in your telescope, bigger aperture means more light which will eventually result in better and clearer picture.

Now you will think of buying biggest aperture telescope that’s fit in your budget but no, there is one drawback also with a big aperture, the size of your device also gets heavy and bulky which will be a big issue for you to carry the device away from the city where you can enjoy night sky with your family. In that case, I will recommend you compact(with less aperture) yet powerful telescope. But if you intend to use it on your terrace or in your backyard then I will recommend the biggest aperture telescope available in your budget.

Magnification and Eyepiece

Second important aspect is magnification or power of telescope which is decided by the quality of eyepiece attached to it. The good thing is it is user replaceable so it is up to us to decide what amount of magnification we want for our device. So you will think “why not use the largest magnification?” but the answer is no, suppose you have a 4-inch telescope and you are using 800x magnification the result will be blurred image. Let me give you an example, you must have a smartphone now at night try to full zoom then click the image you will notice the image is blurred and this happens due to the aperture of the camera in your smartphone. Less aperture causes less light to enter which cause poor quality after magnification. Same thing happens with a telescope.

So, How to decide the right magnification? Simple, you just need to multiply your aperture by 50 if it is denoted in an inch or just multiply by 2 if it is in mm. ex: – suppose the aperture of your telescope is 4inch(100mm) then resulted magnification will be (4inchx50) or (100mmx2)=200x. So now we will buy the eyepiece having a maximum magnification of 200x.

Types of telescope

a) Refracting telescope(Refractors)

There is basically three type of telescope.The first type of telescope is refracting telescope. In this telescope, we use a lens to form an image. This work on a very basic principal, light enters the tube and falls on the lens which focuses the image in the back where the eyepiece is situated.

Advantages:-

  •   It has a very simple design that’s why is very easy to use.
  •   Good for terrestrial use, viewing the moon, Saturn rings, different planets etc. in simple words we can say it is a good substitute for high-end binoculars.
  •  Lens are fitted into a sealed tube so it’s very difficult for dust particle to enter into the tube that’s why it has low maintenance cost.

Disadvantages:-

  • Generally, it has small aperture because making big lenses are bit difficult. So it is costly in comparison with Reflector telescope.
  • It has a long tube which is why the device is bit heavier and bulkier due to this it is a bit difficult to carry the telescope from one place to another.
  •  Sometimes it causes chromatic aberration( In simple terms, we all know that light has different wavelength and when light passes through lens sometimes lens is unable to capture the different wavelengths of light which result in some type of rainbow effect at the side of the lens, this phenomenon is called chromatic aberration).

b) Reflecting telescope

In this type of telescope mirrors are used to form the image. Light enters the tube through the primary mirror then focuses the light to a secondary mirror which deflects the light to the eyepiece.

Advantages:-

  • Manufacture big mirrors are less expensive then lens that’s why it has large aperture due to which it is a bit easier to view distant galaxies, nebula, stars etc.
  •  It is cheaper than refracting telescope having same aperture.

Disadvantages:-

  • The tube is not sealed due to which there is a chance of dust entering the tube which eventually results in high maintenance costs.
  •  Not suitable for terrestrial viewing.
  •  Need to collimate the mirrors before using.

c) Catadioptric/Cassegrain telescope

In this type of telescope, a combination of both lens and mirrors are used to form the image that is why it has both the advantages of reflecting and refracting telescope.

Advantages:-

  • It is compact in size
  • It has sealed tube which prohibits dust particles to enter into the tube so it has low maintenance cost
  • Good for both terrestrial viewing and for observing deep galaxies.
  • It is best for astrophotography because we can attach a wide variety of accessories to it.

Disadvantage:-

These type of telescope is a bit costlier than Reflector Telescope.

Telescope Mount

To provide the stability to our device a mount is must for device. There are basically two types of mount present:-

(i) Alt-azimuth mount→It is a basic mount which helps to move the optics in up and down and side to side directions. Due to its simple design, it is very cheap and good for beginners to use.

(ii) Equatorial Mount→An equatorial mount possesses two axes and also they are tilted which allows the device to aligned the device with earth’s rotational axis. These type of mount is very good for astrophotography and for more advanced use.

Budget

Another important aspect which we should keep in mind before buying a telescope is the budget. One thing you should also remember that buying a good quality telescope the first time (even if it is little bit expensive) is better than again upgrading or buying the different telescope after a year. But don’t worry about that, in this website I will recommend the best telescope for you in every different budget categories.

Collimation is a process through which we align the optics of our telescope to get the best focus through our eyepiece. In simple word, we can say it’s a process to align the mirrors of our reflector. Don’t worry, you don’t have to be an expert to collimate your telescope by yourself. If you understand the process clearly it’s not more than a work of 5 minutes.

Below is an easy 3 steps guide for you to collimate the telescope by yourself with the help of laser collimator.

Things we need:-

a) Allen key (usually supplied with your telescope)

b) Screwdriver (supplied with a telescope)

c) Laser collimator (must buy)

As the name suggest it can be fitted into both 1.25” and 2” reflector, comes with a lifetime warranty so don’t worry about the quality of the product.

Let’s get started:-

We already know our telescope has a three basic components Primary mirror situated at the bottom of the tube, Secondary mirror, and an Eyepiece(see above pic). To collimate the telescope we start with aligning the Secondary mirror first because it has more chances of getting out of alignment. Four screw are present in the back of Secondary mirror holder, three of them are side screw to control the tilt and the screw at the center is for controlling rotational and longitudinal adjustment of secondary mirror(see pic below).

Note- Always remember to put your telescope into a horizontal position before collimating. You don’t want your screw or something to fall on to your primary mirror and damage the product permanently.

Step1– Using Laser Collimator

First, Insert the laser collimator into draw tube and remember to put the Collimator in such a way that the target area should face the primary mirror(as shown above in the picture,more on that in step 3). Now just lock the focuser and collimator tightly.

Step2- Adjusting Secondary mirror

After inserting the laser collimator you will notice that the focus of laser on primary mirror is not at the center(as shown in below picture). Now we try to move the laser to center by adjusting the three screw presented at the back of the Secondary mirror with the help of Allen key. After perfectly aligning to the center we just lock the mirror by tightening the center screw with the help of a screwdriver.

Step3- Aligning Primary mirror

Primary mirrors have a total of 6 screws. Three of them are Locking screw smaller in size used for locking the mirrors and another three are Adjustment screw  bigger in size used for adjusting the mirror( as seen in pic above, step 1). After inserting Laser collimator you will notice that reflection of the laser will be near the target area of collimator but not at the center.  Now to move that to center loosen up the locking screw then move the adjustment screw slowly to clockwise or counter-clockwise direction.

Once the laser is in the center (as shown above) of the target your telescope is perfectly aligned. Just tighten the locking screw in that position and you are ready to go.

Friends, you must be thinking this website “Telescopefever.com” is about telescopes then why is there a post related to Binocular? Because Binoculars are also Telescope, in simple terms binoculars are a pair of telescopes mounted side by side on a metal frame which uses a curved lens to bring the object closer to eyes and also a pair of the prism to create a high-quality image right side up (not inverted like a telescope). Guys if you are having difficulty in deciding a right Binocular for you. Don’t worry, you are at the right place. Here is a 5 step easy guide to help you choose a good Binocular for you.

1) Magnification

Magnification is the number written before x. Suppose you are going to buy a binocular ABC8x40 here ABC is brand name and 8 is the magnification. In simple words, it means the view of the object will appear to be 8 times near than the original position of the object. Let me give you an example, let’s say a bird is at the distance of 800m from you but with this 8x Binocular the bird will appear to be at the distance of 80m.

*Don’t go for magnification higher than 10x- 12x for handheld use just because it is very difficult for hands to get steady. Up to 12x is manageable but let’s say you are using 15x magnification then any small amount of movement of your hand will result in 15 times the vibration of an image. To use Binoculars of magnification beyond 10x-12x get a tripod.*

2) Objective lens diameter

Objective lens diameter plays an important role in choosing a right telescope. The objective lens is the main lens through which light enters into binoculars. Higher the objective lens diameter larger the amount of light enters into it. Results in better image quality in low light condition. It is the number written after x in the name of binoculars. Example, ABC 8×40 here 40(always in mm) is the diameter of the objective lens.

*Higher the diameter of objective lens heavier and bulkier binoculars will be. So buy it according to your need. or you can use a neck strap to compensate the weight*

 3) Lens quality and coating

Binoculars come with a glass lens as well as the plastic lens. Always prefer glass lens over plastic lens because glass lens produces better image quality than plastic lens. There is just one problem with glass lens they partly reflect some light falling on the lens or in simple words it produces glare from the object but does not worry this can be compensated with a right coating.

There are four types of coatings done:-

  • Coated (C): A single layer on at least one lens.
  • Fully-Coated (FC): A single layer on all air-to-glass surfaces.
  • Multi-Coated(MC): Multiple layers on at least one lens.
  • Fully Multi-Coated(FMC): Multiple layers on all air-to-glass surfaces.

*Better the coating higher will be the price.*

 4) Exit pupil

If you are going to use your Binoculars at night or in low light condition then decide according to the size of the Exit pupil. It is a diameter of the image formed on the eyepiece for your pupils to see. During low light condition, a pupil of our eyes opens about 5 to 7 mm so a binocular with an exact Exit pupil between 5-7mm will be good for night viewing.

*To calculate exit pupil just divide objective lens diameter with magnification. For example,  8×40 Binoculars would have an exit pupil of 5mm.*

 5) Waterproofing

Binoculars are made to use outdoor. So some degree of waterproofing is a must. If you are willing to use your Binoculars during river rafting, boating, skiing or any other water sport then buy waterproof binoculars (WP) otherwise use water resistant binoculars for a different purpose.

 Summary

Binoculars are priced from 50$ to above 1000$. Each has their own purpose like some are good for bird watching,  some are for hunting,  some are made for stargazing, some are specialized in sports activities, marine activities and some are for traveling purpose. Before buying any binocular first think what is your primary purpose of buying it and most important what is the budget you can afford then decide.

A telescope mount is very important – it works as a motorized tripod. The main purpose of a telescope mount is to allow you to direct the optical tube at the object and take a good picture of it. You can track the motion of the object – whether it is the moon or a planet – by using a motorized telescope mount.

Motorized mounts are very important in astronomy as they allow for a very precise tracking of the planetary motion. It is important to choose the mount very carefully in order to capture the images of the celestial objects at their best.

1) There are two types of telescope mounts – Altazimuth mounts and Equatorial mounts.

Altazimuth mounts

In case of Altazimuth mounts, the telescope moves on the up-down and right-left axes, just like any photographic tripod.

Equatorial mounts

In case of Equatorial mounts, the telescope moves along the polar axis and is pointed in the direction of the Pole Star.

Equatorial mounts are much harder to use as they require the polar alignment to be perfect. The tracking quality of an Equatorial mount will depend on how accurate the polar alignment is. Also, you need to make use of heavy counterweights to keep the telescopes of in place.

But the advantage is that equatorial mounts allow for a far more accurate tracking of celestial objects. They even improve the accuracy of the most ordinary telescopes.

2) How to Setup an Equatorial Mount?

It is actually quite easy to set up an equatorial mount. Sure, it’s not as easy as setting up an altazimuth mount – which is just like setting up a camera tripod. But once you set up an equatorial mount the first time, you will know how to do it again, for as many times as you like.

The advantage of an equatorial mount is that it only needs to be rotated around one axis so as to maintain the target object in your field of view.

Let’s understand how the Equatorial Mount works…

The planet Earth is tilted on its axis at 23.5°. When the Earth rotates around its axis, the stars in the sky appear to move across the sky through the night.  To follow the movement of the stars, you have to move the telescope slowly in the opposite direction relative to the rotation of the Earth.

When you do this on the altaz mount, you will need to adjust two axes – the altitude and the azimuth. On the Equatorial mount, you only need to keep the polar axis parallel to the axis of rotation of the Earth, and there is no need to adjust it further. Also, you will need to rotate the other axis of the telescope called as the declination axis in order to focus on the target.

Follow the tips given here to easily set up an Equatorial Mount

You will need the following to get started.

A Compass – The compass should be easy to read under the red light.

Markers – For marking the position of the tripod leg once the mount has been aligned.

Red light torch – Essential for your vision; protects your eyes against the dim light.

Spirit level – Allows you to level the tripod easily.

You will also need a protractor, scissors and stiff cards.

Mark the position of the tripod

The tripod has to be placed in a single location. Once you decide where you place the tripod within your property, mark the positions of the legs on the floor.

Next, set up the tripod. Extend its legs to a suitable height, and make sure that the top of the tripod is as level as it can be. Tighten the bolts. Mark the height of each of the tripod’s legs, so that you will know where and how to position it the next time.

Setting up the equatorial mount

The very first thing to do when assembling the mount is to ensure that it is perfectly level. For this you will need to use a spirit level to check the level of the tripod head, and then attach the mount head on that. Once the mount has been completed, it has to be positioned roughly towards the north.

Okay, now let’s set the mount in the direction of true north. You can find the direction of the true north in your area on the Grid Magnetic Angle Calculator. You can then use the compass to adjust the mount in the direction of true north and away from the magnetic north.

In this case, make sure that the polar axis is properly aligned and set it for the latitude of your area or wherever you are mounting the telescope. You can check your position on the website iTouchmap.com. Once you know your latitude, mark a right-angled triangle on the stiff card which has one of the angles the same as your latitude.

This triangle can be used as a template to check the amount of adjustment needed to be made to the mount in order to get the perfect polar alignment. Hold the triangle against the mount, with the longest side of the triangle aligned against the polar axis, with the spirit level placed on the shortest side.

Right, you can now move the altitude adjustment bolt until the spirit level is perfectly level. The polar axis should be parallel to the Earth’s axis.

Focus on the Polaris.

The Polaris or the North Pole lies within an angle of 1° of the rotational axis of the Earth. Point the telescope towards it so that it is perfectly parallel to the polar axis of the EQ mount. Make sure that the Polaris is within the field of view of the finderscope and the lower power eyepiece.

Next, loosen the polar axis clutch to ensure the accuracy of the polar alignment. Once the Polaris is aligned accurately, it should move in a small circle within the field of view of the finderscope. In case it is not, make tiny adjustments to the azimuth and altitude of the mount head till it is so. You can now use the Equatorial Mount freely.

3) Our Favourite Equatorial Mount

There is a famous saying that “Your Telescope is only as good as your Mount” an we believe that. A good & stable mount can drastically improve your viewing experience. If you ask me, my favourite is  CG-4 German Equatorial Mount and Tripod from Celestron.

Features:-

  • Accepts Vixen-style dovetail plates
  • German equatorial mount and tripod
  • Counterweights: one 7.0 lb/3.2 kg, one 4.0 lb/1.8 kg
  • RA and DEC slow motion controls and setting circles
  • Tripod: adjustable height, 1.75″ steel legs, center brace/accessory tray

 

So this is how to set up an Equatorial Mount. Feel free to ask any question you have on your mind in the comments below! 🙂