All about backyard birds

This series of the well respected manufacturer from Japan features a low cost models that still comes with a lot of quality features. The models are equipped with a porro prism that are superior and have much better dept of field then some other models. This Kowa Yf 8x10 quality optics puts it in the range of excellent bird watching binoculars.

This Kowa YF series binocular is from the popular Japan manufacturer that produces good quality binoculars for some time.  It features a  new porro prism and it’s a nice thing to see in these new binocular series. The binoculars equipped with the Porro prism offer much better depth of field, the field of view is also wider and  as these binoculars have lenses that are spaced wider apart than the roof prisms the stereoscopic image that comes out of them is a little better then other binoculars. The design also makes them less expensive because porro prism binoculars don’t require phase correction add on and reflective coatings that is required in roof prism ones. This makes them often optically superior.   

Check the price of Kowa binoculars 8 times 30 caliber here.

This review is about Kowa YF 8x30 binocural:

Kowa YF binoculars line

This manufacturer is well admires for the excellent quality binoculars, recently there is new ranges of the product coming to the market that is much more affordable and still comes with lots of quality features. The manufacturer is producing some of the parts in china and in this way lowers the cost of the production. In this way the quality remains and the price is lowered, a good news for the consumer.

In recent times some pretty good binoculars are coming from China, especially the ones where the parent company is form out of the country, in this case from Japan.  Sometimes we think of China as a source of cheap and low quality products, but in this case that is not true. Looks like Kowa make sure that their products are well manufactures and to high standard.

At this moment Kowa is producing two models in the YF series, the first one with 6c magnification and the second one comes with 8x magnification.  We will see in this review if the 8x30 binocular comes to its name:

Main Design Highlights 

  • 100% water & Fog Proof
  • Field of View: 396 feet at 1000 yards
  • Fully multi-coated lenses
  • Eye Relief: 16mm
  • Good quality wide neck strap
  • Can be used by children
General Use:      4/5 stars 
Bird Watching: 
 4/5 stars
Marine Use: 
 3/5 stars
Hunting:   3/5 stars
Outdoors & Sport: 4/5 stars

The Kowa YF 8x30 Body

When you first hold the binocular it will feel light and comfortable, and the design looks good, as well as the quality. By the first look it feels like it is a more expensive and more higher  price binocular.

The Build Quality 

These binoculars look very solid and robust, even if it is lightweight it looks like it can stand up to some punishment. It looks like in normal use it will last and are not made of cheap material.

The frame of this binocular is covered with rubber, this is a standard to all new models on the market, it protects them from damage in case you drop them. This models is equipped with 2 types of rubber armour manufacturer points out. When you handle the product you don’t have the means to determent if this is beneficial, so it is hard to know how much it helps. We just have to trust them on this one.

The rubber that coats the binocular is somewhat harder, maybe more than some other models, but it will protect it from bumps, scratches and damage. This rubber serves more the one purpose, it makes the body less reflective, this is important for bird watchers when you have to stay as less visible to the birds. The birds a usually timid and will be weary of humans.

When you flip the binocular and look at the underside, there is a depression in the rubber that extends on each of the barrel, this is done to help the grip when you look thru the binoculars. By adding this to the design you are guided to where to put your fingers at the right spot, this makes them nicely balanced in your hand.

Metal was used for the bridges between the two barrels, it’s a good feature that makes the design more sturdy, plastic is newer a good option and its good news it was not used here. The lenses are positioned 4mm inside a body, that is welcomed feature,  that gives them good protection in case the binocular falls down or something strikes it.

Waterproof & Fogproof Design

This model is waterproof and dust proof, this protects it in all conditions you can find yourself in. Rain, sand, and fog will not damage this binocular. It’s an all weather model that will not spoil your view.

One great feature is that the air inside the Kowa 8x30 YF binocular was replaced during the manufacturing with nitrogen gas. This replacement prevents the binocular from fogging from inside. All of us who used binoculars in low temperature knows that they are prone to fogging, this one can safely be used in all temperatures. Including low temperatures, high humidity and rapid temperature changes.   The other benefit of this is that as the moisture cannot enter the inside of the binocular it will last much longer and be corrosion safe.

The Eye Cups

The eyepieces are made coated with soft rubber, and sits fairly comfortable on the eyes. The ocular lens is 19mm diameter. While the eyecup is made of 39mm external diameter.

I like the twist up mechanism on the eye-cup and it works excellent, there is a 4 fixed stop feature on them, so eyeglass wearers can easily adjust the settings to their need. Very important and gives a lot of flexibility to the user to suit their personal needs. There is am 16mm eye-relief maximum installed on the model, this is enough for most people and will be happy to use this model and leave the glasses on. For the users with no glasses eyecups will extend all the way in the full position.

Focusing Features

The focusing wheel is well made, its easy to raach even with gloves on, very nice. The wheel itself is made of hard plastic and covered in soft rubber. Its diameter is 35mm and looks easily reachable by all ages.

Focusing mechanism is geared in a way that it takes 3/4 of a turn to go from one end of focus to the other. This means that if you want to focus from infinity to the minimum point of 2.1m or 6.9 feet it takes less revolution than some other models. This can also mean if you over-turn you can struggle to find the fine focus on exactly the right setting. But getting used to it will take a short time, and will not be a problem to most users.

Interpupillary Distance Settings

You can also adjust the distance between the center of ocular lenses. If you open an close the central hinges on the bridge you can adjust it from 5.1cm to maximum of 7.2cm. This is done to adjust to the difference between peoples eyes to make it easier to view.

Diopter Adjustment

There is a diopter adjustment ring located on the right barrel, this ring needs to be setup only once and then your good. This ring is made with markings so once it is setup you just have to remember the markings in case you accidentally move it again. This diopter settings are used to setup your binocular focus according to your personal eyesight. Most of the binoculars today have this easy feature.


Binoculars Weight

Kowa 8x32 binocular is light weight and this is very good, the weight is just 475g (16.7oz), in the range of the mid-size class this makes them one of the lightest. For sure lots of users will find this a welcome feature.

This light weight dos not comes from cheap material, like some other models on the market out there. Kowa 8x32 binocular is sturdy and well made, and don’t have that cheap feeling that some of the same price range binoculars have. The material used in this series are good quality and looks robust.


This series come is most compact dimensions (Length x Width x Height): 11.8 x 16 x 4.8cm (4.6 x 6.3x 1.9in). This puts them in range with most other roof prism binoculars, and when you compare them stands similar in quality. This dimensions do extend a little more when the eyecups are drawn out fully.

When you hold the binocular in your hand it is interesting how easy is to reach the focus wheel. Even if you wear gloves or have small hands this is easy to do. This makes it a good model for women and children. 


In the balance category I think that Kowa 8x30 binoculars stand good, and the design help a lot in that direction, as mentioned before the depression under armour on the barrels gives you the points where to put your hands to grasp it correctly. The medium size binoculars don’t have so much importance on balance like the larger models, but still it feels good when it is nice and steady in your hand. This comes especially if you plan to hold it for longer times. Birdwatchers and any other users will find this helping when going outdoors

Kowa YF 8x30 Optics

The Prisms and their coatings

When you compare this series prism and coating and the lower price tag, I still comes with good quality optics. The usage of the superior BaK-4 glass on the prism helps it to produce a nice, sharp and clear image. Other models in the same category sometime uses a BK-7 lower quality glass.

As mentioned before this porro prism dos not require expensive coating like foof prism, and it si much easier to produce. This makes this product less expensive and you get more for the buck, a high quality view for less money, a win-win situation.

Lenses quality 

This YF series binoculars comes with a multi-coated lenses, and all air-to-glass surfaces are done with a more than one anti-reflective coating. This gives a much brighter image, and increases the low light quality of the binoculars.  

This reflective coating can make so much difference in quality of the picture, some larger objective lenses with less or no coating can produce much lower quality image than smaller lenses with high quality anti-reflection coatings. Out there on the market you can find models that offer anti-reflection coating just on the outer surface. This models will still be marketed as with snit-reflection coating features but provide only minimum difference from the models with no coating. The most cheapest ones offer no coating and it is recommended not to buy these models.

Optical Stats

Field Of View

This binocular come into a wide angle range, the field of view is 132m at a distance of 1000 meters ( 396 feet at 1000 yards= 7.5). This makes a great feature and a true highlight on these binoculars and will satisfy most people who wants to use them outdoors for hiking, sport or bird watching.

Minimum Focusing Distance

The minimum focus distance is at 2.1 meters or 6.9 feet. You can use them to watch thing up close but this is not the main purpose of these binoculars. Its best comes in watching objects that are farther away. But still makes it’s a good up close binocular.

Eye-Relief Feature:

Eye- relief is good, setup to 16mm maximum and will be good enough for most people with or without glasses.

Image Quality Statistics


The test was made in sunny as well in overcast morning, it performed very good, and it can be concluded that this is very similar to other models in the same class. Maybe slightly better than some other  models in the same price range.

Brightness and the 8x30 Configuration

You fill find yourself often when you go outdoors in a sub-optimal light conditions, morning, sunset or wooded areas that provide low light atmosphere. As the birds are most active at this time it is natural that you will spot them most easily if you observe them then. Larger objective lenses binoculars can easily let in more light in these conditions, but also comes with more weight. This makes them harder to pack in your backpack or luggage.

To put this into perspective:  All 8x42 binoculars have exit pupil of 5.25 and all 8x32 have exit pupil of 4. This makes it easier for the larger one to let in light, and in theory will work better than the smaller ones.

But one more important thing must be taken in account, the quality of the optical system. This quality will be the final factor in producing a bright and sharp image. In the low light conditions the quality of the design will be a key factor in performance, as well as optical coating. The exit pupils are not the primary factor. The lenses with a good quality coating can get in more light than larger lenses with less or no coating. So when looking for a good binocular take all of these into the account.

Difference between 8-power and 10-power binoculars

Seen through 8-power binocular

Seen through 10-power binocular


In the images presented above, the magnification is greater on the right picture, with 10-power binoculars used. But you can notice that more of the scene can be visible in the left picture where the 8-power binocular was used. You see the whole cardinal.

That is why with 8-power you get to see more of the scene, but on the other hand you get more magnification with the higher 

Colour Fringing

In this area this models perform very good if not excellent. No sign of color fringing was spotted when the object was watched. This binoculars performed well in all of these tested area and did very good an all light conditions. 

Softening of Image

Small but hardly noticeable amount of softening was spotted on the image just on the periphery of view. But nothing to be to much lower the image quality.

Contrast & Colour Reproduction

The color on this binoculars look very natural and feels fine. The sharpness of the image is also very good, and when you look at the contrast there is nothing that you can usually  find on low price range binoculars. Very good pass on this one.

Kowa did a good job on this one and I was surprised how good it looks, manufacturer did a better job than expected in similar mid-sized range models.

Included Extras & accesories:

Neck Strap

You get a strap with this YF series and it looks nice and well made. The quality is good, but not as good as more expensive models. There is a small curve in the strap that makes it hange more natural around your neck or shoulder.

The Case

The binoculars comes in a nice case, there is room to store it fully extended, there is one loop on the back of the case for your belt, in this way you can put it on your waist if you like. The only thing that is missing is extra pockets inside s case. So you cannot store extra things.

The Lens Covers

The eye lens covers are made of rubber and will fit good on the binoculars.

The objective lens covers are made from plastic and fit well into to the ends of the barrels of the binocular and should not fall off that easily. Each of them has a loop which can be used to attach them them to the neck strap.

 The piece comes with objective lens covers that are made of plastic but fits good, and will not fall off.  There is a loop provided that can be attached to the strap to secure them more.  

You will get in the package a instruction manual that has all the right details how to operate the  binoculars, from adjusting the eyecups to focusing and lens cleaning. You can find all of these things inside this booklet.

Kowa comes with a Guarantee
Kowa provides a limited lifetime warranty for this binocular that you get inside a box.


The good:

This Kowa YF series binoculars are surprisingly good for the price range. The best features are wide field of view, compact design and weight that is minimum for that size. The view quality and the brightness are well above this type of binoculars, Kowa did a god job in producing a lower priced product and still a very good quality one. Looks and feels like a far more expensive cousin.

The less good

Some parts are made of hard plastic like the focusing wheel, but still do good job. Also the case and lens covers are not top of the line like on more expensive models. But that sad I think all other main parts are good quality, and if the price is lower because of these small things than I don’t mind. The lenses and the body is made of good and quality material and you can see that some sacrifices had to be made on the cases and lens covers to keep the price down. For me I am fine with that. For the price that you pay this is one excellent product.  

Excellent Low Cost/Cheap Binoculars for Bird Watching and General use.

These Kowa 8x30 YF binoculars are great for general wildlife observation and even some types of hunting where size and weight are important and like most mid-sized binoculars these make a good all-round general use binocular.

These binoculars are great for camping, traveling and bird watching, its image quality puts them in a range of excellent bird watching binoculars. Compact size and wide field of view makes them also ideal for sport events like racing or similar activities.

Because of the price range and the fact that it can be use with small hands this binoculars are great for children and women and highly recommended.


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