Comments on: How to tell which binocular is better? http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/ All About Shopping Tue, 07 Feb 2012 07:01:20 +0000 http://wordpress.org/?v=2.3.1 By: Tom A http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-336 Tom A Thu, 06 Dec 2007 13:02:43 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-336 After you've decided what size you need, you test for sharpness and alignment. You can do this at the shop. For sharpness: Make sure they're steadily held (on a tripod, or against a shelf. Focus on a star, or if it's daytime, on a small reflection from a streetlight or likewise. Move the binoculars so the glint goes slowly towards the edge. See how close to the edge you can get before the sharp glint becomes elongated. Most binoculars won't get to the edge, but see how close some of them go. For alignment: Set them up, and look through only one barrel. Put an object very close to the edge of the field of view at the side. Look through the othere barrel to see if it's the same distance from the edge. Then repeat this, but checking for alignment at the top or bottom of the field of view. After you’ve decided what size you need, you test for sharpness and alignment. You can do this at the shop.

For sharpness: Make sure they’re steadily held (on a tripod, or against a shelf. Focus on a star, or if it’s daytime, on a small reflection from a streetlight or likewise. Move the binoculars so the glint goes slowly towards the edge. See how close to the edge you can get before the sharp glint becomes elongated. Most binoculars won’t get to the edge, but see how close some of them go.

For alignment: Set them up, and look through only one barrel. Put an object very close to the edge of the field of view at the side. Look through the othere barrel to see if it’s the same distance from the edge. Then repeat this, but checking for alignment at the top or bottom of the field of view.

]]> By: water_skipper http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-335 water_skipper Mon, 03 Dec 2007 10:34:12 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-335 The other answers are good, but I have another strategy for you to consider: the "exit pupil." Take the object and divide it by the magnification to get the exit pupil. For example, with 10x70mm you divide 70mm by 10x and get a 7mm exit pupil. A bigger exit pupil will give you more field of view and be easier on the eyes. If the exit pupil is too small, it's like having tunnel vision and it's like staring at a bright television in the dark so it can be unconfortable. The other answers are good, but I have another strategy for you to consider: the “exit pupil.” Take the object and divide it by the magnification to get the exit pupil. For example, with 10×70mm you divide 70mm by 10x and get a 7mm exit pupil. A bigger exit pupil will give you more field of view and be easier on the eyes. If the exit pupil is too small, it’s like having tunnel vision and it’s like staring at a bright television in the dark so it can be unconfortable.

]]> By: mathematician http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-334 mathematician Fri, 30 Nov 2007 12:29:33 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-334 1) Power: how much magnification do the binoculars provide? Usually a mid-range is best, say 10x or so. Hogher pwer is harder to hold steady without a tripod, lower can be good depending on the use. You want to be able to see everything you want and that is more possible with smaller powers. 2) Objective: how large in the front opening? If you are doing astronomy, you want a larger opening to collect light. Many astronomical objects are large, but dim. A mid-range magnification and larger objective allow these dim objects to be seen. On the othe rhand, if you are doing bird-watching, the objective isn't as important, although it can affect resolution: bigger objective lenses allow smaller objects to be resolved. The problem with larger objective is the same as for large power: they can be hard to hold because they are heavy. The combination of power and objective size is given on most binoculars: a 7x50 has a power of 7 and an objective of 50 millimeters. 3) Coatings: Good binoculars will have coatings on all lens and prism surfaces to enhance light transmission. While this may seem paradoxical, the nature of light allows thin coatings to actually let more light through. If you look down the from of the binoculars, you should see a greenish tinge, but check the details to be sure. The coatings also cut down on glare in your image. 4) Weight: pick binoculars that won't make your arms tired when you hold them. Either that or use a tripod. Usually, more than about 32 ounces is too much for extended periods of time. 1) Power: how much magnification do the binoculars provide? Usually a mid-range is best, say 10x or so. Hogher pwer is harder to hold steady without a tripod, lower can be good depending on the use. You want to be able to see everything you want and that is more possible with smaller powers.

2) Objective: how large in the front opening? If you are doing astronomy, you want a larger opening to collect light. Many astronomical objects are large, but dim. A mid-range magnification and larger objective allow these dim objects to be seen. On the othe rhand, if you are doing bird-watching, the objective isn’t as important, although it can affect resolution: bigger objective lenses allow smaller objects to be resolved. The problem with larger objective is the same as for large power: they can be hard to hold because they are heavy.

The combination of power and objective size is given on most binoculars: a 7×50 has a power of 7 and an objective of 50 millimeters.

3) Coatings: Good binoculars will have coatings on all lens and prism surfaces to enhance light transmission. While this may seem paradoxical, the nature of light allows thin coatings to actually let more light through. If you look down the from of the binoculars, you should see a greenish tinge, but check the details to be sure. The coatings also cut down on glare in your image.

4) Weight: pick binoculars that won’t make your arms tired when you hold them. Either that or use a tripod. Usually, more than about 32 ounces is too much for extended periods of time.

]]> By: skymaster http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-333 skymaster Thu, 29 Nov 2007 19:36:13 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-333 With binoculars, the most common size used by amateur astronomers is 10 X 50. That means a magnification of 10 and an objective lens of 50mm. These are not so heavy that you need a tripod to hold them still. Also you can by Canon binos now of the 30x40 size which have adaptive optics to remove the shaking of the image. Buying Binoculars is a bit like buying telescopes, so important things are 1 Go to a reputable dealer 2 Get to try them out on the sort of objects you want to view 3 Only get a reputable brand, Takahashi, Celestron, Nikon, Pentax etc. 4 Never buy from a department store 5 Get binos using BAK4 glass 6 Look through the eyepieces, there should be a fully circular view with no obstructions 7 You should be able to focus on infinity and close objects 8 The lenses should be multicoated and give off a greenish hue Buy binos made in Japan or US if possible as quality is better. Expect to pay at least US$100 up to as much as US$500. Just buy the bet you can afford, (and use comfortably) there is no other rule. Recommendations on what to buy can be found at websites such as, and others. Hope that helps. With binoculars, the most common size used by amateur astronomers is 10 X 50. That means a magnification of 10 and an objective lens of 50mm. These are not so heavy that you need a tripod to hold them still. Also you can by Canon binos now of the 30×40 size which have adaptive optics to remove the shaking of the image.

Buying Binoculars is a bit like buying telescopes, so important things are

1 Go to a reputable dealer
2 Get to try them out on the sort of objects you want to view
3 Only get a reputable brand, Takahashi, Celestron, Nikon, Pentax etc.
4 Never buy from a department store
5 Get binos using BAK4 glass
6 Look through the eyepieces, there should be a fully circular view with no obstructions
7 You should be able to focus on infinity and close objects
8 The lenses should be multicoated and give off a greenish hue
Buy binos made in Japan or US if possible as quality is better. Expect to pay at least US$100 up to as much as US$500. Just buy the bet you can afford, (and use comfortably) there is no other rule.

Recommendations on what to buy can be found at websites such as, and others.

Hope that helps.

]]> By: jess http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-332 jess Thu, 29 Nov 2007 11:56:45 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-332 To tell which binocular is better: I would say by how good it can focus on something that you are looking at or by how great it works and if there is too much buttons or knobs to hit to get the focus just right. Most people look at how it focuses and how it looks. Hunters usually look for how it looks and what type of brand it is. Scientists probably would look at the quality of it and how good it works for there type of research they are doing. I hope that answers your question! To tell which binocular is better: I would say by how good it can focus on something that you are looking at or by how great it works and if there is too much buttons or knobs to hit to get the focus just right.

Most people look at how it focuses and how it looks. Hunters usually look for how it looks and what type of brand it is. Scientists probably would look at the quality of it and how good it works for there type of research they are doing.

I hope that answers your question!

]]> By: Bobbyp416 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-331 Bobbyp416 Mon, 26 Nov 2007 15:54:46 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-331 If you're planning to use you binoculars for night- time observing, the first rule in optics is: The more aperture, the more light- grasp. Which means, if you have a choice between a pair of 7X35 (meaning 7 power, 35mm objective lenses) vs. a pair of 10X60 (10 power, 60mm objective lenses), your best choice would be the 10X60s. The larger the objective lenses, the brighter the object will appear. Some binoculars are so large, though, they require a tripod mount to be stable enough to see anything... If you’re planning to use you binoculars for night- time observing, the first rule in optics is:
The more aperture, the more light- grasp.
Which means, if you have a choice between a pair of 7X35 (meaning 7 power, 35mm objective lenses) vs. a pair of 10X60 (10 power, 60mm objective lenses), your best choice would be the 10X60s.
The larger the objective lenses, the brighter the object will appear.
Some binoculars are so large, though, they require a tripod mount to be stable enough to see anything…

]]> By: Will P http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-330 Will P Fri, 23 Nov 2007 18:45:24 +0000 http://youthinside.org/2007/11/23/how-to-tell-which-binocular-is-better/#comment-330 You should probably try looking through it. You should probably try looking through it.

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