.Fujinon 25 x 150EM .

Back..Modern telescopes are excellent value for money thanks to mass production, but short of using a binocular eyepiece adapter, which in the past I have found most unsatisfactory, we are restricted to the use of one eye whilst using them.

It is generally accepted that the main reason us humans have two eyes is in order to perceive depth, or to give us 3D vision, but the reason that we have been blessed with two fully functioning highly complex optical devices in our heads is far more than just our ability to perceive depth.

The images sent via the optic nerves to the brain are combined instantaneously to give us an enhanced view of our environment. This is far more noticeable under low light conditions when our eyes are working to their limits, and any minor optical aberrations are amplified. This is a simple point to prove. Pop outside on the next clear night: close one eye and look at the stars, keep the eye closed for a while and make a mental note of the faintest star visible with the other. Now open both eyes. Hey presto, more stars - but look again, you will not be able to see any fainter stars but your two eyes perceive more. This is not some kind of magic but just the eyes working as they should, individually making up for minor imperfections in the other.

So why for sake this gift by using only one eye with a telescope?

.Die hard telescope fans will argue the advantages of interchangeable eyepieces, computer location and tracking, photography etc. - all very good points, but my reality has been spending more time fumbling in the dark trying to find just the right eyepiece and less time enjoying.

However, a simple pair of 5x17 binoculars fixed to the eyepieces of the Fujinons allows me to see such things as the shadows of Jupiter's moons, and the Cassini division in Saturn's rings, not to mention breathtaking views of the moon. This obviously speaks volumes for the quality of the optics, but the lack of right ascension drive does become a problem at such a high magnification.

However, the lack of a drive system is not a problem when the binoculars are used in their correct 25 magnification format. Due to this relatively low magnification and a field of view of 2.7 degrees, even in the worst case an object will take a little over ten minutes to traverse the field of view. Location of faint objects is also made easy with the use of computer software to convert right ascension and declination to the altazimuth calibrations on the binocular mount. With the binoculars wide field of view, even locating such things as bright stars on a summer afternoon is made relatively simple. As for the unsuitability for photographic use, I must agree, but it is still possible to photograph some of the brighter objects in the sky with a little care and patience.

.One aspect of the Fujinon binoculars that took me by surprise was their ability to cut through light pollution. From my home next door to Gatwick Airport and in particular the runway approach lighting, it is quite normal to be able to read the large print in a newspaper at any hour of the night.

This is obviously not conducive to deep sky observation, but when I point these binoculars to the most orange-light-polluted region of the sky, thanks to their huge object lenses and the high quality low dispersion glass used in their manufacture, I am rewarded with a field of coloured jewels against an orange background - truly a spectacular site. I have yet to use these binoculars from a really dark sky sight and find it hard to imagine what awaits me.

Another major factor where binoculars score over telescopes is in their port ability and erect image, opening up a whole host of uses during the hours of daylight. The Fujinon 25x150EM's are just about on the limits of practical port ability, but a view over the English Channel from Beachy head is well worth the logistics of man handling 70Ibs of binocular, mount and field tripod. Even from one's own back garden one doesn't need to be a plane spotter to marvel at the site of a Boeing 747 trailing at 35,000 feet.

Of course the most important thing with any optical instrument is a good, steady, well balanced mounting. Fortunately most observation binoculars, come with a satisfactory mount and some with a field tripod as well. With the Fujinon 25x150EM the mounting and perfect balance allows rock steady viewing and fingertip pressure to move the binoculars to any position, with the exception of 5 degrees around the zenith, physical constraints in the mounting making this impossible. Still, even with the 45 degree angled eyepieces this is not the most comfortable area to observe and anyway in our latitude one has only to wait a short time for stars to traverse this area.

Back to top
Please send comments and/or error reports to the