A Work Commenced January 25 2023

Over the last year, I’ve taken a deeper interest in Nikon Porro binoculars. In previous communications, I’ve described how much I’ve been enjoying both the 8 x 30 Nikon E II and the 10 x 35 Nikon E, the performance of which have really spoiled me. In more recent times I field tested the lower power 7 x 35 Aculon A 211 and Action EX and while both were enjoyable, I felt that their excessive field curvature at the edge of their 9.3 degree fields left a little something to be desired. I briefly considered the 7 x 35 E but its rather restricted field of view of 7.3 degrees didn’t sit right with me. To my way of thinking, a 7x glass is already compromised owing to its lower power – call it ‘pain’ if you like -and there ought to be some ‘gain’ in return, and that meant an enlarged field of view. So, in summary, I was after a 7 x 35 glass that offered better optics than either the Nikon Aculon or the Action EX, especially off axis.

I knew and read about some classic Porro prism binoculars from yesteryear that sported enormous fields, sometimes up to 11 degrees or more, but I wondered whether their edge of field performance would also let them down. So I began looking at classic Nikon Porros that offered something of a compromise and 9.3 degrees seemed to fit the bill the best. I’d lose a little magnification but gain a whole half a degree over my Nikon E II. But which model to choose?

Having never tested any of these out in real life, it was somewhat of a guessing game, but I had to start somewhere. The condition of the instrument ranked high on my list of priorities too. I wanted an instrument that was in good condition, with no large build up of internal haze on the prisms or, worse still, fungus. Did such an instrument exist? The answer, I’m delighted to say, is yes!

Doing some browsing on Fleabay, I came across a very intriguing instrument. This was a Japanese-made 7 x 35 Widefield 9.3 degree binocular in what looked like excellent working condition. It even had the original eyepiece and objective caps as well as the black bonded leather case – Japanese made also. And it was going for £85 inclusive of free delivery! The seller had the presence of mind to include some photos taken through the objective lenses against a plain white background, which allowed me to assess the condition of the interior lenses and prisms. It looked amazingly good for the age, which the seller informed me dated to the mid-1980s. So I pulled the trigger and sure enough it arrived two days later. Opening the package, I removed the case from the wrapping to find the instrument perfectly positioned inside. When I picked it up, I was quite taken aback by its rather large frame. This was a longer-barreled binocular than I expected any 35mm Porro to be. Take a look at it in comparison to my 10 x 35 Nikon E below:

Upon inspection with a flashlight I confirmed that the innards of the instrument were indeed pristine. How on God’s Earth could a binocular that first saw light when I was a middle schoolboy still look so good after all these years? Well, the excellent condition of the chassis – with a couple of minor scuffs on the metal rims on the instrument’s mid-section– and the fact that it still had its original caps and no internal haze suggested to me that it must have been very lightly used. But it must also have been stored in a good, dry place to prevent the growth of internal fungus.

The instrument is fully coated – most probably using a single layer of MgF₂ on all optical surfaces. Thus I fully expected that it would not be nearly as bright as instruments treated to a full modern multicoating. More on this later.

Unlike the later E series, the focus wheel, which also appears to be made of some kind of tough plastic, is much larger and placed right between the barrels. It was a bit stiff coming right out of the cold box, which had travelled the length of the country from the seller, but after I ‘thawed’ it out, as it were, it came back to life moving smoothly in both clockwise and counter clockwise directions, with no free play or backlash.

Splendid!

The eyepiece housings appear to be made of  some kind of tough plastic too, as were the rim of the objective barrels, which surprised me. The eyecups are made from rubber though, a significant departure from the hard plastic of the old classic Zeiss Porros. The dioptre ring is very similar to that of my Nikon 10 x 35 E, which has a tendency to wander while in field use, but I soon remedied that by fitting a very tight rubber o ring immediately under it which keeps it in place much better. The chassis is ‘armoured’ in an attractive, textured leatherette which is very nice to the touch as well as to visually inspect.

Despite it being a big glass for a 35mm format, I was surprised that it tipped the scales at only 665g – much lighter than the Action EX and also lighter than the Aculon 7 x 35! The only disappointment with the instrument was a somewhat frayed neck strap, which I might have got by with, at least for a while. But having taken a short stroll with it, paranoia got the better of me, and I decided to replace it with a nice, old fashioned leather lanyard which supports its moderate weight well.

The handling of this instrument is superb. I can wrap my hands round those curves in the mid-section with wonderful ease and comfort, using my middle fingers to fall naturally on the deeply ridged focus wheel. Less than half a turn clockwise brings you from closest focus (measured at 4.1 yards) to a little bit beyond infinity. All in all, this instrument, which has travelled nearly 40 trips ’round the Sun since it saw first light, is an ergonomic delight!

Bravo!

Optics

After about an hour of warming the instrument up to room temperature, I noted that all was well. The optics were clear both internally and externally. And it was at this moment that I brought it outside for a gander. Wow! This thing is super sharp! But what really impressed me was how big the sweet spot was: it was in a totally different league to the Nikon Aculon or the Action EX, which always gave me that funny goldfish bowl feeling as soon as my eyes drifted to the periphery of the field. No, this instrument was optically far superior to those other Nikon’s both on axis and especially off axis. Pure, indulgent pleasure! To access the entire field, I had to turn down the rubber eye cups in order to get a good view of the field stops, just like I had done with my Nikon E 10 x 35. Glare was surprisingly well suppressed for a singly coated optic like this; far better, for example, than my multi-coated Zeiss Jenoptem from the same era. It has a slight yellowish colour cast, very much like that achieved by a very mild photographic warm-up filter.

Both longitudinal and lateral colour correction are very well controlled. Hardly any was seen even on the most difficult high-contrast targets. Barrell distortion is mild. My first stroll with the binocular was during dull, overcast conditions. I brought it to one of my local patches, where a fallen tree occupies the far end of a pond. I’ve come to use this to judge how big the sweet spot is in many binoculars I test because it crosses the entire field. I could immediately see that its optical behaviour was much more like that of my Nikon E II 8 x 30 than either the Aculon or Action EX models. Far superior off axis performance, with the sharpness being maintained nearly right to the edge. Vertical correction was not as good though, but that’s true even with my Nikon E II 8 x 30 and virtually all others I’ve tested.

My next tests took place in brilliant winter sunshine, on the formative afternoons of January 25 and 26. The views in this fabulous light were breath-taking. I could see details on the far hills that simply didn’t stand out in my tests with the Aculon and Action Ex. I quickly came to realise how little refocusing I was doing owing to the instrument’s impressive depth of field. The focus is a little stiffer than a top-rated birding binocular, but this turned out to be largely immaterial, owing to the generous field depth. I’m really coming ’round to appreciating this wonderful optical property! In bright sunlight, one hardly notices the slight yellow tint of the old Nikon Widefield 7 x 35, but as the light fades more tests conducted with my Nikon E II showed up the clear advantages of modern broadband multi-coatings. Venturing out just before sunset on a cold and cloudless late January day, I glassed some tree trunks about 80 yards in the distance. Comparing the images side by side, I could see that the Nikon E II 8 x 30 was already pulling ahead of the old classic. It had an unquestionably brighter image and better contrast between the browns of the tree bark and the green moss and lichen mottling its surface.

In yet another test, carried out in the early evening of January 26, I mounted both instruments on a tripod and studied the images of a beautiful crescent Moon sinking towards the western horizon. Apart from more internal reflections in the 7 x 35 I was genuinely impressed how comparable the images were. The Moon had a very faint fawn tint to it that I didn’t really find distracting, comparing it with the marble white colour served up by the Nikon E II 8 x 30. Colour correction was actually better on the Nikon Widefield 7 x 35 than the E II, both on and off axis. I would estimate its sweet spot is a good  75% of the field, about the same, in fact, as the 8 x 30. Illumination drop off was a bit more pronounced on the 7 x 35 though, but the effects of mild field curvature near the field stops could be easily focused out – just like the venerable E II.

Venturing out after midnight in the wee small hours of January 26, the Moon had set and the full glory of the winter night sky was presented to me. Cassiopeia, Perseus and Taurus were now hanging low on the north-western sky, Gemini was near the meridian and brilliant Arcturus was rising fast in the east. I enjoyed fabulous views of the Hyades and Pleiades. Framing the Auriga Messier open cluster trio in the enormous 9.3 degree field proved child’s play. I swept up the Beehive cluster in Cancer, and looking eastward I enjoyed some marvellous views of the Coma Berenices Cluster. Stars were beautiful pinpoints across most the field of view, with only slight distortion seen on the brighter stellar luminaries near the field stops. Despite its lower overall light transmission, this is a better glass than the Aculon or Action EX 7x 35s for stargazing. What it lacks in light gathering power is easily offset by its better corrected field of view.

After I had received the instrument and done some preliminary testing, I did a search to see if others had reviewed the Nikon 7 x 35 Widefield 9.3. My searches came up empty at first, as all I got was a number eBay links here and there showing some photos of the instruments for sale. Puzzled I began to read older threads on past Nikon Porro prism binoculars and eventually hit on the issue: this model was apparently known as the Nikon Action 7 x 35. What’s more, there were apparently several incarnations of the Action, with the later models being switched to production in China. What nailed it for me was finding a very interesting post on Birdforum dating to January 2012 made by Henry Link, an experienced US-based binocular enthusiast who discussed the same model. You can read his report of it here. What’s more, he came to largely the same conclusions about this binocular as I did: a Mark1 Nikon Action 7 x 35 Widefield. Furthermore, in his post he described the results of tests of this binocular, concluding that it was one of the sharpest shooters in its genre. It was, in his own words, “as good as it gets.” Link also provided a really good explanation for why the Action Mark I worked so well. It has a longer than average focal length – a full 140mm in fact – making it a slower f/4 optical system. Increasing the F ratio of any telescopic system is a way to reduce all geometric(Seidel) aberrations as well as chromatic aberration.

I contacted Henry to tell my story with a few photos of the instrument. He confirmed that it was the original Nikon Action as described.

Concluding Thoughts

What a marvellous find! To say that I’m delighted with it would be an understatement. This is a higher-class binocular than anything Nikon is currently churning out in the 7 x 35 format. But it raises as many questions as it answers. Why give up on such a great optical design? Can it be resurrected? It’s also taught me a valuable lesson; there is nothing new under the Sun and great optics can be had from pretty much any era if you’re lucky enough to stumble on them!

Neil English’s up-and-coming book, Choosing & Using Binoculars: a Guide for Stargazers, Birders and Outdoor Enthusiasts, will also include a chapter on classic instruments from the past. He would like to thank Henry Link for interesting discussions on this binocular.

 

 

 

De Fideli.