Birdwatching binoculars are usually very compact with the objective lens diameter rarely bigger than 42mm. Birdwatching usually takes place in daytime and bigger, bright binoculars have no added value. Resolution and absence of optical errors are thus far more important. Many ornithologists also prefer higher magnifications, so 10x magnification is the preferred choice for many. Quality of the focusing mechanism is also one of the more important properties for ornithological use of binoculars. Summary of the most common properties of binoculars for birdwatching is given below:
Because birds are mostly observed during the day, most binoculars used for this are compact, with 28-36 mm objective lenses, which are bright enough for watching during the day. The best thing about them is that they are light-weight and small, so their users do not have to carry so much weight and can easily wear them around their necks, without causing any pain.
All bird-watchers usually hold binoculars in their hands for a longer period and that is why it is much more advisable for them to purchase one with a Roof prism design. Roof prism binoculars are more compact and ergonomically more comfortable to use.
Especially those who are very experienced and have a calmer hand, often prefer a 10x magnification because it offers better options for viewing details. Such binoculars are the most useful for larger birds that are slower.
Because there is the largest selection among binoculars and you will get the highest quality for your money, we recommend 8x42 configuration. It is the most comfortable for viewing and is suitable for open terrains as well as for forests. It offers a wider field of view, brighter image and (unfortunately) fewer details compared to 10x42. For the first step in the world of birdwatching, 8x42 is definitely most recommended because it provides a better field of view and is better for observing smaller and faster-moving birds. 8X42 binoculars are easy to hold in hand without excessive shaking of the image.
For anyone wearing eyeglasses, a minimum of 17-18mm eye relief is recommended (20mm even more optimal). It is good if the exit pupil is as large as possible, at least 4mm, preferably even 5mm or more. From this, it is clear that 8x42 is usually a better choice than 10x; however, it is true that some people rather „risk the comfort“ for seeing more details. It is very important that you check the eye relief before purchasing the optical device- if it is less than 15 mm, it will be much more difficult to observe with glasses.
The birds can move very fast and because of this, focusing is being used a lot. It is great if the focus can be easily and quickly changed, so the central focusing system is the most recommended. All other focusing systems are usually not suitable for bird watching.