Choosing the right binoculars for bird watching, or birding, can
really make the difference between starting a great, enjoyable hobby,
and getting frustrated and never going birding again. It is simply that
crucial. There are some activities that rely so heavily on your first
experience that is its bad you probably won't do it again. Birding is
one of those activities. If you can't find the bird, or if you can't
focus clearly enough to either ID, or see the details in its colors, it
can be very frustrating. When you hear people talking about how
beautiful a bird is and you are having a hard time even seeing the bird,
it can be maddening! I want to tell you what to look for in getting
binoculars that will make your new hobby so much more enjoyable!
Compromise is a word we will be using a lot when selecting a binocular for birding. The trick is trying to understand what you want out of the optic, and how you will most likely use the optic. For example it is better to have really large lenses in binoculars, they let in more light and allow viewing in low light much better, they are also heavy and can be tiresome if you have to carry them around all day. A smaller lens may not let in as much light, but will be much easier to carry. You have to decide what is best for you!
What do all the numbers mean?
The first thing you will notice when looking at binoculars is there are a lot of numbers! This is what some of those number mean! You will see things like 8x32, 10x42, 5x25, and everything in between. The first number is the magnification, the second number is the diameter of the objective lens(the big lens in the front) usually in millimeters. You may see FOV and a number usually in feet. like 200, 315, 180. this is the diameter if the view usually at 1000 yards. More about these later.
Size: Choosing the size of your binoculars is dependent upon several factors. Do you plan to hike, or do you plan to watch from you porch or car? Are your hands steady, or do you have slight tremors or shakes? These all play a part in making this decision. You want to find a balance between weight, the size of the objective lens, and the way you intend to use them. The compact binoculars out there while small and easy to carry, will not be as sharp or function as well in low light, and can be harder to keep steady. The larger ones usually have big objective lenses and have sharp clear images even in fading light, but they can be heavy. There are mid size models with objectives from 30-35mm and full size models with objectives from 40-45mm. The full size will give you almost all the detail you can process with your eye, but it is a bit more weighty. You have to have an idea about your use.
Roof vs Porro Prism: This determines the configuration of the binoculars more than anything. The porro prism is used in the classic binocular shape, The Roof prism is shaped straight, more like a telescope. There is little optical advantage to either, but the cost of manufacturing is more in the roof prism. So they are usually more expensive and they are a little more compact. There are 2 main materials these prism are made of, BK-4 and BAK-7. The BK-4 is considered to be superior because the BAK-7 can cause blurs around the edge of the image.
Objective lens sizes: As we touched on earlier, this is the lens on the front of the binoculars, Its main function can be considered to be gathering light. the larger the lens diameter, the more light that you can collect. For instance a 35mm lens will gather about 2x the light of a 20mm lens. This is based on the formula area=pi(r)². However the larger lens will weigh more and be less comfortable to carry. Most birder recommend 42mm to be the largest size to carry for long periods comfortably.
Coatings: Coating are applied to the glass lenses in several ways, but they are meant to help with light transmission, decrease reflection, and improve color fidelity. The best binoculars are fully coated, meaning that every lens element inside the binoculars is coated. There are coated only some lens elements are coated and non-coated. This treatment can increase the transmission of collected light dramatically. The coating on the lenses is very thin and a little delicate, care must be taken when cleaning the lenses so as not to damage the coating.
FOV: This is a measure of how wide os a viewing angle lenses have. think of it like this, when you look through binoculars at an object, the circle you see is your field of view. they measure this in either angles or in ft/1000yds. If you see a value like 315ft/1000yds that means that if you are focussed on an object that is 1000 yards away, then the circle you see is 315ft in diameter. If you are given a value in degrees, like 6.5 degrees, you can convert to feet by multiplying the degrees by 52.5. The wider the field of view the easier it will be to find birds and track their movement, since birds typically move fast being able to quickly find them is essential for a good outing. For birding you want and angle of 6.5 or 341ft at 1000yds.
Eye relief: This is how far the image is projected out of the eyepiece towards your eye. This can be a problem for people who wear eyeglasses like myself. If you wear glasses you want to look for long relief or adjustable eyecups that can be retracted to accommodate for the glasses.
Theses are the big things one must consider when buying a new set of binoculars for birding. This is by no means an exhaustive list of things to consider, but it has hit the big ideas. Understanding these terms and how they work can make selecting your first birding binoculars easier. The more frustrating thing is being able to find all the information about a certain product. Use all the resources you can to find out all you can before you spend your money!
Happy Birding!
Compromise is a word we will be using a lot when selecting a binocular for birding. The trick is trying to understand what you want out of the optic, and how you will most likely use the optic. For example it is better to have really large lenses in binoculars, they let in more light and allow viewing in low light much better, they are also heavy and can be tiresome if you have to carry them around all day. A smaller lens may not let in as much light, but will be much easier to carry. You have to decide what is best for you!
What do all the numbers mean?
The first thing you will notice when looking at binoculars is there are a lot of numbers! This is what some of those number mean! You will see things like 8x32, 10x42, 5x25, and everything in between. The first number is the magnification, the second number is the diameter of the objective lens(the big lens in the front) usually in millimeters. You may see FOV and a number usually in feet. like 200, 315, 180. this is the diameter if the view usually at 1000 yards. More about these later.
Size: Choosing the size of your binoculars is dependent upon several factors. Do you plan to hike, or do you plan to watch from you porch or car? Are your hands steady, or do you have slight tremors or shakes? These all play a part in making this decision. You want to find a balance between weight, the size of the objective lens, and the way you intend to use them. The compact binoculars out there while small and easy to carry, will not be as sharp or function as well in low light, and can be harder to keep steady. The larger ones usually have big objective lenses and have sharp clear images even in fading light, but they can be heavy. There are mid size models with objectives from 30-35mm and full size models with objectives from 40-45mm. The full size will give you almost all the detail you can process with your eye, but it is a bit more weighty. You have to have an idea about your use.
Roof vs Porro Prism: This determines the configuration of the binoculars more than anything. The porro prism is used in the classic binocular shape, The Roof prism is shaped straight, more like a telescope. There is little optical advantage to either, but the cost of manufacturing is more in the roof prism. So they are usually more expensive and they are a little more compact. There are 2 main materials these prism are made of, BK-4 and BAK-7. The BK-4 is considered to be superior because the BAK-7 can cause blurs around the edge of the image.
Objective lens sizes: As we touched on earlier, this is the lens on the front of the binoculars, Its main function can be considered to be gathering light. the larger the lens diameter, the more light that you can collect. For instance a 35mm lens will gather about 2x the light of a 20mm lens. This is based on the formula area=pi(r)². However the larger lens will weigh more and be less comfortable to carry. Most birder recommend 42mm to be the largest size to carry for long periods comfortably.
Coatings: Coating are applied to the glass lenses in several ways, but they are meant to help with light transmission, decrease reflection, and improve color fidelity. The best binoculars are fully coated, meaning that every lens element inside the binoculars is coated. There are coated only some lens elements are coated and non-coated. This treatment can increase the transmission of collected light dramatically. The coating on the lenses is very thin and a little delicate, care must be taken when cleaning the lenses so as not to damage the coating.
FOV: This is a measure of how wide os a viewing angle lenses have. think of it like this, when you look through binoculars at an object, the circle you see is your field of view. they measure this in either angles or in ft/1000yds. If you see a value like 315ft/1000yds that means that if you are focussed on an object that is 1000 yards away, then the circle you see is 315ft in diameter. If you are given a value in degrees, like 6.5 degrees, you can convert to feet by multiplying the degrees by 52.5. The wider the field of view the easier it will be to find birds and track their movement, since birds typically move fast being able to quickly find them is essential for a good outing. For birding you want and angle of 6.5 or 341ft at 1000yds.
Eye relief: This is how far the image is projected out of the eyepiece towards your eye. This can be a problem for people who wear eyeglasses like myself. If you wear glasses you want to look for long relief or adjustable eyecups that can be retracted to accommodate for the glasses.
Theses are the big things one must consider when buying a new set of binoculars for birding. This is by no means an exhaustive list of things to consider, but it has hit the big ideas. Understanding these terms and how they work can make selecting your first birding binoculars easier. The more frustrating thing is being able to find all the information about a certain product. Use all the resources you can to find out all you can before you spend your money!
Happy Birding!
We have a good selection of birding binoculars and other optics at http://www.binocularworld.net.
We offer fast personal service and free shipping on most orders. We are
adding to our selection constantly, and appreciate any suggestions on
products we should carry. If you have any questions about the article or
about optics in general please visit our site and let us know.
