New Binocular Resolution Test Results (1 Viewer)

Atomic Chicken said:

Greetings!

It's been quite a while since I started my binocular resolution testing project... I've been experimenting, trying new things, refining the process, and generally having WAY too much fun considering the nature of this endeavor!

OK... on to the details.

First off, a few changes in the methodology from my original post on this topic. I've improved the binocular resolution test chart I've been using, which now consists of a precision laser photoplotted film emulsion sheet of 9" X 12" size. The sheet is broken into two sections, the upper section being for horizontal resolution testing (consisting of vertical parallel lines) and the lower section being used for vertical resolution testing (horizontal parallel lines). Each section is divided into 20 test squares of 1" x 3/4" size. Each of the two 20-square section consists of 5 squares across by 4 squares down. Each square contains evenly spaced lines and spaces of the width in question, with the widths starting at 0.001" in the top-left square and increasing to 0.020" width and spacing in the lower-right square. The chart is placed on a specially machined clipboard holder attached to a tripod, EXACTLY 17.19 feet away from the binocular objective lens. At that distance, every 0.001" is exactly one arcsecond - making conversion unnecessary. I just see what the smallest numbered square that is resolvable into individual lines, and I have instant arcsecond resolution equivalent.

Lighting is kept uniform, and each new pair of binoculars measured is clamped into a specially machined binocular holding strap-clamp mounted to a tripod. When viewing through the binoculars, no part of my face ever touches the binoculars in order to avoid vibration inducing errors. Each pair of binoculars, once clamped, gets re-distanced to the target by hanging a pendulum from the front of the objective lens of the binocular to the floor... where the tripod is moved backward or forward in order for the pendulum tip to align with a previously measured line drawn on the floor. This keeps all test results perfectly equal - with longer length binoculars getting no added advantage due to their objective lenses being closer to the target.

I have no reason to be biased in this testing - I already own all of the binoculars I tested along with several other pairs that were not tested... the testing was kept completely scientific, unbiased, and honest for all optics being examined. I have no reason to be more or less loyal to any particular brand, as I don't own stock in any of the companies and I really do believe that the major brands are all producing superior products - each in their own unique and distinctive way.

OK... Enough about the methodology - here are the results. I did not measure every pair of binoculars I own - as 3 pairs are on loan to friends and one pair is currently missing (not stolen, I hope...). I also did not bother testing most of my "cheap-o" low-end binoculars, choosing only a few of these "instruments" for baseline comparison purposes. I also tested 2 monocular instruments and a spotting scope, although the spotting scope would not focus at such a close distance so the target was placed twice as far away and resulting readings were cut in half to compensate.

All of the below test results are given as a pair of standardized arcsecond resolutions, the first number is the horizontal resolution and the second number is the vertical resolution. The lower the number, the better the resolution performance:


Monocular and Spotting Scope Test Results
================================

Nikon Monarch 800 Laser Rangefinder (6x) H 13 Asec V 13 Asec
GuardForce 6x-12x Monocular (At 6x) H 11 Asec V 10 Asec
GuardForce 6x-12x Monocular (At 12x) H 8 Asec V 7 Asec
Nikon Spotter XL 16x-47x Scope (At 16x) H 4 Asec V 4 Asec
Nikon Spotter XL 16x-47x Scope (At 47x) H 2 Asec V 2 Asec


Binocular Test Results
================

Pentax SP 10x50 H 5 ASec V 5 Asec
Minox BD 8x32 H 6 Asec V 7 Asec
Nikon HG 8x32 H 6 Asec V 6 Asec
Nikon HG 10x25 H 5 Asec V 4 Asec
B&L Discoverer Roof 7x42 H 8 Asec V 8 Asec
B&L Discoverer Roof 10x42 H 5 Asec V 6 Asec
Brunton Echo 8x32 H 7 Asec V 7 Asec
Leica Trinovid 7x42 H 7 Asec V 7 Asec
Zeiss Victory 8x20 H 8 Asec V 7 Asec
Tasco 8x21 (#165RB) H 9 Asec V 11 Asec
Rugged Exposure 10x25 WP H 10 Asec V 10 Asec
Rugged Exposure 10x42 WP H 6 Asec V 6 Asec
Barska 16x32 H 5 Asec V 6 Asec


The above optics are not listed in any particular order, the list started out being the order in which I tested them then I moved a few around to group optics from the same company together.


OK... A few observations. First off, if resolution is the only factor you are really interested in for binoculars, then 10x binoculars are what you should be buying - with the Nikon HG 10x25 clearly leading the pack for this round of testing. I've often marveled at the incredible edge-to-edge sharpness of the 10x25 HG's, but I've never realized until today how much they give the "big guns" a run for their money in terms of overall sharpness. Sure... they do not perform as well in low light conditions, but during daylight hours they REALLY can't be beat. In the past, I've very carefully compared the Nikon HG 10x25's to the relatively new Leica Ultravid 10x25's, and I'll swear upon all that is holy that the two cannot be distinguished optically by any test that I can devise. If resolution is your holy grail, then either of these two fine binoculars will blow you away... I guarantee it.

OK... more observations. The Barska 16x32 results CLEARLY show that you are FAR better off buying a quality pair of 10x binoculars rather than a cheap pair of 16x binoculars - ESPECIALLY in light of the fact that I couldn't hold the damned things still enough to save my LIFE when trying to examine the test chart freehand off the tripod. Dim little things too... hardly a thing comes to mind that would make me want to recommend them!

The Rugged Exposure (Rebranded "Barska") 10x42 waterproof roof prisms continue to show their incredible value considering their $70 price tag - easily holding their own when compared to pricier 10x options. Too bad they are built with all the quality of a particle board bookshelf and glare like a lighthouse when viewing birds near the sun... but at $70 you shouldn't be expecting perfection anyway - the quality of the optics is already WAY underpriced as is!

I was impressed by the overall VIEW of the test chart only once during all this testing, a moment where it looked like someone had suddenly switched on the lights and everything just seemed to "glow" with brilliant razor perfection and clarity. Yes... I'm speaking of the Leica Trinovid 7x42 of course... what else could I have possibly been talking about?

The Minox BD 8x32 and Brunton Echo 8x32 are both excellent performers considering their price tags... while the Zeiss Victory 8x20 were somewhat disappointing considering their fairly HIGH price tag. The Tasco 8x21 and Rugged Exposure (Barska) 10x25 were both thrown in for laughs... actually more like rivers of tears considering the DISMAL and PAINFUL viewing experience these dim fog-tubes provide.

Both B&L Discoverer roof prism models did quite well considering their price. The Nikon HG 8x32 did ALMOST as well as the Pentax SP 10x50 in terms of resolution - another surprise! The Nikon HG 8x32's are the best 8x binoculars I tested in terms of resolution... with a clean, bright image to match.

I cannot stress this enough: Resolution is absolutely NOT the only important factor to be considered when selecting a pair of binoculars, if it were then I would be using 10x binoculars all the time and wouldn't have my well known bias toward 7x optics. Other factors to consider include brightness, color rendition, lateral chromatic abberations, field of view, depth of field, geometric distortions, edge sharpness, ruggedness, ergonomics, and weight. For me, the Nikon HG 8x32, HG 10x25, and Leica Trinovid 7x42 just hit all the right "sweet spots" for my own preferences.

All-in-all, quite a few surprises uncovered in this evening's testing... I hope you enjoyed reading about it as much as I enjoyed doing the actual tests!

More to come in the future....

Best wishes,
Bawko

Click to expand...

Humboldt Jim said:

Wow! Great test Bawko. When will you publish the target?

I may be gilding the lilly here, but I cant help but wonder how subjective opinions would match up with the resolution test. But that's another project!

Click to expand...

Atomic Chicken said:

...10x25 HG's, but I've never realized until today how much they give the "big guns" a run for their money in terms of overall sharpness. Sure... they do not perform as well in low light conditions, but during daylight hours they REALLY can't be beat.

Click to expand...

Atomic Chicken said:

All-in-all, quite a few surprises uncovered in this evening's testing... I hope you enjoyed reading about it as much as I enjoyed doing the actual tests!

Click to expand...

henry link said:

Bawko and elk,

I don't have much time for a reply as I am about to leave for a week's vacation with no computer. Bawko, your eyesight actually looks to be quite good from your results, better than 20/20, but you would need to have better than human eyesight to see detail as small as 14", which is the probable 2" actual resolution of your Leica 7X42 multiplied by its magnification. The 7" you reported for that binocular multiplied by 7x is 49" which is very good eyesight acuity but almost certainly far below the actual resolution of the binocular. The astigmatism I was refering to would be in the binoculars, not your eyes. If the axis of the astigmatism happens to be aligned or nearly aligned vertically it will cause a loss of resolution in the horizontal bars but have much less effect on the vertical bars. A star test would indicate if this is the cause.

I suppose I think "resolution" is a bit of a red herring in binoculars. It's certainly true that some binoculars look "sharper" than others, but the magnification is so low that any good quality binocular is not really being pushed to its resolution limit when you simply look through it. There may be problems of many sorts in the image, but in my experience it takes a very bad or very defective binocular for its actual resolution to be worse than eyesight acuity. I may be wrong but I think if these experiments are done repeatedly the averaged result with the good binoculars will wind up being the experimenter's eyesight acuity divided by the binocular's magnification. In other words I think it is essentially an eye test.

Henry

Click to expand...

xenophobe said:

If that's true, none of the opinions by anyone would ultimately matter, nor that of any subjective review of any particularly well-designed binocular.

What I think is necessary is a definition of terms. Obviously some people have different ideas of what one word or term may mean alongside someone else's.

resolution The fineness of detail that can be distinguished in an image

acuity Sharpness, clearness, and distinctness of perception or vision

Obviously the commonly accepted definitions of the word has no solid meaning here on this forum with arguments based on semantical insanity. If in fact they do, obviously these are not the same. Sharpness, clearness and distinctness can be had at low or high resolution. Just as in an arguement spawned by Wehr on another thread, he's confusing the definition of the two as well.

Example: My Zeiss 10x40b Classics; They are extremely sharp, clear, crisp and distinct through their field of view, although, compared to the Ultravid 10x42 at long ranges, do not resolve as fine a detail as the Ultravids do. WITHOUT the aide of extra magnification, which shouldn't be needed to determine if there is a loss in resolution when it is visually apparent. Where, why or how this occurs does not change the fact that, ultimately, there IS less visible resolution and subjecting the optics to tests if the molecular alignment of the optical glass is/isn't in alignment with Pluto on a rainy day does not for one minute change the fact that one pair of binoculars may well indeed visulally resolve better than another, regardless of whomever may be viewing.

In case I have it completely wrong, I am misunderstanding the English language (hardly) and am just not clued in to some grand elitist conspiracy to re-write the dictionary based on their optical expertise, then please school me. If neither is the case, then there should be some solid, agreeable definition of terms so that nit-picking can be done on actual comments instead of peoples' use of specific words..

Click to expand...

xenophobe said:

...
acuity Sharpness, clearness, and distinctness of perception or vision

...

Click to expand...