The small size of the Eterna makes it easy to take along on a vacation or an outdoor adventure. Don't worry about the weather. The Eterna is waterproof, fogproof, and built to last. Fully multi-coated optics optimize light transmission for bright views on cloudy days. Brunton covers the Eterna with a limited lifetime warranty.
Fully Multi-coated Lenses
Increase light transmission with multiple anti-reflective coatings on all air-to-glass surfaces. Emerald Fire™ coatings.
Enhances resolution and contrast through roof prisms.
Optimize light transmission.
Appreciated for a streamlined shape and durability.
Provides a secure, non-slip grip.
Twist up and down for comfortable viewing with or without eyeglasses.
Center Focus Wheel
Adjusts both binocular barrels at the same time.
Right Eye Diopter
Adjusts for differences in a user's eyes. Located by the right eyepiece.
Can be mounted using standard ¼-inch threading. Adapter sold separately.
Optics are sealed with O-rings to prevent moisture, dust, and debris from getting inside the binocular.
Barrels are filled with nitrogen gas to inhibit internal fogging.
These are very nice binoculars. The optics are sharp and bright and I did not detect any fall off or distortion near the edge. The depth of field is good and it is easy to focus on an object. Eye relief is long, they work well with glasses and I like the 3 mm exit pupil. The field of view is listed as 270 ft at 1,000 yards, which seems pretty typical for glasses of this size. However, I am used to the 340 ft. FoV of my old 8x22 Orion Ultra Views and I definitely felt the difference.
The Eternas are listed as weighing 12 oz. and they are probably a little heavy for 8x25s and perhaps a little big. On the other hand, they feel extremely sturdy and are pretty stable when viewing. The twist up eye-cups have four stops and they stay in place under normal pressure. I thought both the focus wheel and the diopter adjustment were pretty stiff. Handling was okay but they don't seem to balance naturally in your hands (and I'm a 6 ft tall male, with fairly large hands).
I compared the Eternas with a Pentax 8x25 DCF SW. The Eterna's optics seemed a bit better than the Pentax's and they felt much sturdier (and a little heavier). I think the Pentax's would be better suited for casual use, for example if you want something handy walking around town or in the country. They are lighter and easier to carry with only a minimal sacrifice in the optical quality (I'm not sure it would noticeable in a single blind test). They also cost roughly half as much as the Eternas. However, if you wanted something for serious hiking or hunting or any rough use, or if you're want to get the best optics you can afford, I'd say the Eterna is the better choice.
I recently purchased these binoculars to pack with me on a bicycle journey in Africa. I wanted something compact, but also quality to help me ID birds on the road/trail, many of which were completely new species to me. I knew that light gathering and field of view would be a challenge with a compact binocular. I was pleasantly impressed with the Brunton Eterna. I found the binoculars to be very easy to pack around during biking, light and durable enough for me to carry around my neck on very bumpy/technical dirt roads, and to perform exceptionally well, delivering a quality image throughout the day. The binoculars are sturdy, easy to focus, and deliver a surprisingly sharp image for 25's. I have, and prefer, the 8x power. I have no trouble holding the image stable with the 8x. A 10x power of these binoculars may be difficult to hold steady. An issue I often have with small binoculars is getting the eyecups in the proper position for both of my eyes. The Bruntons are easy to manipulate and stay in position while in use. The focus dial is also easy to use and stays put. There is a very fine line between in and out of focus, but after a few uses, I learned how to focus quickly. Overall, I was very impressed with these binoculars and was not expecting such sharp image quality from a compact binocular. These binoculars are a great choice for hiking or biking trips where you need a portable pair of binoculars. Of course, a larger objective lens would produce a higher quality image and allow for more light gathering, but the trade-off of portability of the Brunton Eterna is a good compromise for general birding if you need to pack light. The light gathering was far superior to what I was expecting for such a small objective lens. I look forward to continuing to use these binoculars on all of my bike rides.