8x42 Allbinos custom ranking (1 Viewer)

I decided to take the Allbinos 8x42 data and re-rank them.

Basically, I isolated only the optical metrics (Transm, ChromAberration, Astigmatism, Distortion, Coma, EdgeBlur, EdgeDarken).

The final score for each binocular is a product of three values:
Final score = A * B * C
A = Transmission
B = Chromatic Aberation
C = Astigmatism + Distortion + Coma + EdgeBlur + EdgeDarken

EDIT:
It is essential that the ranking formula must contain multiplication (this way, zero transmission = zero score, no questions asked) ... and in this case transmission and color fringing control are singled out as absolute must-have; a binocular must pass these two qualifications before considering any further.

Additive is what Allbinos is already using and there serious problems with it.
Essentially you could theoretically make a binocular out of welder's glass that is so dim and black that even the sun is barely visible so that
Black useless Binocular = 0 + 10 + 10 + 10 + 10 + 10 + 5 + 5 = 60
$1000 Binocular = 13 + 8 + 7 + 8 + 7 + 8 + 4 + 4 = 59

So a black useless binocular can be made to rank higher (if we use high grade welder glass on it) than a normal $1000 binocular when the ranking formula is purely additive.

So many of these measurements among the top ranked 3 or 4 binoculars must imperceptible to a lot of people and one wonders if they are really important.

By coincidence about 6:30 PM this past evening I was out on my deck using my Zeiss 7x42 Victory T* FL. I Thought I would check the edges of it's view to see if I could discern the astigmatism or blurring they are reputed to have. I couldn't see much at all. I would guess that the "sweet spot" in that binocular covers about 97% of the view, maybe more! The allbino's astigmatism measurement above on the Zeiss 8x42 is 8.8 or something like that and the blurring factor was 6 and I don't know what it means.

Machines can see things I can't see.

Bob

I've done a similar thing before, but I think if you are trying to isolate optical metrics you can't leave out the internal reflections and FOV scores. Glare control / blackening and FOV are pretty important aspects of optics.

It definitely does get interesting if you exclude the exit pupil truncation and especially the ridiculous IPD scores.

I certainly agree with eitanaltman, as glare/flare is probably one of the biggest issues in some binos and distinctly leads to optical issues. FoV, meanwhile, is very important and in some cases a lower FoV results in sharper edges and vice versa.

Also, I see an issue with your model: this should not be a multiplicative formula, but an additive one, e.g. optical quality = A+B+C. Your formula causes small differences in each variable to result in massive overall differences. It is impossible to argue that any of the three variables you list is proportionally more important than another, and that is kind of the basis for using multiplicative models.

I think this is the reason subjective rankings are popular.

I dont see CA unless it's really bad, and I dont really care about darkening or blurring at the edges. Like glasses, I dont look through the edges. So for me those things are a non starter for judging.

jremmons said:

Also, I see an issue with your model: this should not be a multiplicative formula, but an additive one, e.g. optical quality = A+B+C. Your formula causes small differences in each variable to result in massive overall differences. It is impossible to argue that any of the three variables you list is proportionally more important than another, and that is kind of the basis for using multiplicative models.

Click to expand...

Additive is what Allbinos is already using and there serious problems with it.
Essentially you could theoretically make a binocular out of welder's glass that is so dim and black that even the sun is barely visible so that
Black useless Binocular = 0 + 10 + 10 + 10 + 10 + 10 + 5 + 5 = 60
$1000 Binocular = 13 + 8 + 7 + 8 + 7 + 8 + 4 + 4 = 59

So additively a black useless binocular can be made to rank higher (if we use high grade welder glass on it) than a normal $1000 binocular.

As such it is essential that the ranking formula must contain multiplication (this way, zero transmission = zero score, no questions asked) ... and in this case transmission and color fringing control are singled out as absolute must-have; a binocular must pass these two qualifications before considering any further.

Using an additive model and including the following aspects: transmission, chromatic aberration, astigmatism, distortion, coma, blurring, darkening, whiteness, reflections, AFoV, AoV, interior barrels, gives us a "perfect" score of 103. Some examples of rankings, listed as percentages:

8.5x42 Swarovision: 85.6
8x42 EDG: 84.3
8x42 Alpen Rainer: 76.5
8.5x44 Kowa XD: 76.4
8x42 HGL: 76.4
8x42 Victory FL: 76.3
8x44 Peregrine XP: 74.4
8x42 Ultravid HD: 73.7
8x42 DCF ED: 71.6

Now, I put perfect in quotation marks above as these fully objective stats mean nothing; allbinos loves incredibly low edge distortion and fully flat fields. For some users such as myself, their eyes cannot accommodate for the "rolling ball effect" that comes with lack of pincushion distortion and so these binos with perfectly flat fields are completely useless. I think when using allbinos, the best option is to look through each model's test, decide which variables are important to you, and add those up to get a rough estimate of which binoculars "should" be on your watchlist. For me, I really like a CA-free image without much glare, but for others, CA control may be completely unimportant and instead edge sharpness may be of particular importance.

In other words, try for yourself, buy for yourself.

MagpieCorvidae said:

Additive is what Allbinos is already using and there serious problems with it.
Essentially you could theoretically make a binocular out of welder's glass that is so dim and black that even the sun is barely visible so that
Black useless Binocular = 0 + 10 + 10 + 10 + 10 + 10 + 5 + 5 = 60
$1000 Binocular = 13 + 8 + 7 + 8 + 7 + 8 + 4 + 4 = 59

So additively a black useless binocular can be made to rank higher (if we use high grade welder glass on it) than a normal $1000 binocular.

As such it is essential that the ranking formula must contain multiplication (this way, zero transmission = zero score, no questions asked) ... and in this case transmission and color fringing control are singled out as absolute must-have; a binocular must pass these two qualifications before considering any further.

Click to expand...

But this is modeling; you have to make sure your model fits your data. This is where, in true statistical modeling, you'd be looking at things like the graphs of the residuals vs. fitted, etc. Obviously, the black useless binocular you mention does not fit the model being presented for "normal" binoculars. Or, if you REALLY wanted your model to fit, you could include A *(B+....Z).

MagpieCorvidae said:

I decided to take the Allbinos 8x42 data and re-rank them.

Basically, I isolated only the optical metrics (Transm, ChromAberration, Astigmatism, Distortion, Coma, EdgeBlur, EdgeDarken).

The final score for each binocular is a product of three values:
Final score = A * B * C
A = Transmission
B = Chromatic Aberation
C = Astigmatism + Distortion + Coma + EdgeBlur + EdgeDarken

EDIT:
It is essential that the ranking formula must contain multiplication (this way, zero transmission = zero score, no questions asked) ... and in this case transmission and color fringing control are singled out as absolute must-have; a binocular must pass these two qualifications before considering any further.

Additive is what Allbinos is already using and there serious problems with it.
Essentially you could theoretically make a binocular out of welder's glass that is so dim and black that even the sun is barely visible so that
Black useless Binocular = 0 + 10 + 10 + 10 + 10 + 10 + 5 + 5 = 60
$1000 Binocular = 13 + 8 + 7 + 8 + 7 + 8 + 4 + 4 = 59

So additively a black useless binocular can be made to rank higher (if we use high grade welder glass on it) than a normal $1000 binocular.

Click to expand...

This seems kind of subjective, can you tell 90% transmission from 88%?

So why is that so important?

jremmons said:

But this is modeling; you have to make sure your model fits your data. This is where, in true statistical modeling, you'd be looking at things like the graphs of the residuals vs. fitted, etc. Obviously, the black useless binocular you mention does not fit the model being presented for "normal" binoculars. Or, if you REALLY wanted your model to fit, you could include A *(B+....Z).

Click to expand...

A simple multiplication resolves all these problems without having to resort to advanced methods and statistical modelling. Also, a binocular out of welders glass is still a binocular, since it transmits "some" light and magnifies. That was chosen as an extreme example to illustrate the point and it gets worse for any other case ... for instance the Tasco had a transmission of 50%

I could machine the Tasco raw glass materials to higher precision and make a Tasco precision God binocular:
Perfect Tasco = 5 + 10 + 10 + 10 + 10 + 10 + 5 + 5 = 65 ... and it now ranks *way* higher than the $1000 binocular of the earlier example.

Addition is simply a poor way to go about this. (If anything, I would rather make all metrics multiplication instead)

Your simplification doesn't really work, though. Using your extremes, two binoculars that are 100% similar in all aspects but, for instance, transmission, in which one scored a perfect 100%(15pts) and the other a 50%(7.5pts) would result in one binocular have an "optical quality" score of double the other - something which is clearly inaccurate.

This is why you cannot apply multiplicative properties here, as you cannot quantify the proportional effect each variable has on overall optical quality.

ceasar said:

So many of these measurements among the top ranked 3 or 4 binoculars must imperceptible to a lot of people and one wonders if they are really important.

By coincidence about 6:30 PM this past evening I was out on my deck using my Zeiss 7x42 Victory T* FL. I Thought I would check the edges of it's view to see if I could discern the astigmatism or blurring they are reputed to have. I couldn't see much at all. I would guess that the "sweet spot" in that binocular covers about 97% of the view, maybe more! The allbino's astigmatism measurement above on the Zeiss 8x42 is 8.8 or something like that and the blurring factor was 6 and I don't know what it means.

Machines can see things I can't see.

Bob

Click to expand...

Bob,

And you can see things that most people can't see, like sharp edges on the 7x42 FL!

Here's what Frank D. had to say about the 7x42 FL's edge sharpness in his Optics Talk review:

"The Zeiss suffer(s) from noticeable astigmatism around the outer edge of the image…I would say, conservatively, the outer 25%. The [$300] Zen Ray seem(s) to have a similar percentage of the image distorted, maybe slightly greater, but in the case of the Zen Ray it is field curvature. This does give one the impression of greater depth of field under certain conditions."

Zen Ray 7x36 ED, Zeiss 7x42 FL and Nikon 7x35 E co

Whether it's astigmatism or field curvature or both, "clearly" there's something fuzzy going on with the edges of the 7x42 FL, which has been reported by many who have owned or used it.

I don't think that Arek is referring to the edges when he measures astigmatism, but in the centerfield. Some binoculars have slight or more than slight astigmatism throughout the field of view, which will make stars appear less than "punctiform" (to use Claudio's term on CN), the brightest showing spikes (this is in "good seeing" conditions).

Out of the binoculars I still have, the Swift 804 Audubon MC has the least amount of astigmatism. Stars are perfect points or balls for Mag. 1 stars.

As to edge sharpness, Arek rated the 8x42 FL as being sharp to about 81% of the FOV (with a margin of error of +\- 3%). Being that the 7x42 FL has nearly a degree more FOV than the 8x42 (8.57* vs. 7.7*), it would be quite impressive if it was also sharp to 81% out, let alone 97%. My 8.8* 8x30 EII is sharp to almost 75% from the center, and that's quite good, fall off after that is gradual. It has the best edge sharpness of the three 8x30 EII samples I've owned.

If other 7x42 FL owners hadn't remarked about this model's less than stellar edges, I would have guessed that you got a good sample and Frank got a bad one, but having read your posts and finding that your eyes are immune to most aberrations and distortions that other people see, I'd guess that the 7x FL's 97% sharp edges are due to your Übermensch eyes rather than the optics.

Are you an organ donor? If so, and you die before I do, please leave your eyes to me, because with them, I could use almost any pair of binoculars and be happy.

Brock

jremmons said:

Your simplification doesn't really work, though. Using your extremes, two binoculars that are 100% similar in all aspects but, for instance, transmission, in which one scored a perfect 100%(15pts) and the other a 50%(7.5pts) would result in one binocular have an "optical quality" score of double the other ...

Click to expand...

Fifty percent transmission is a significant optical deficiency. So, yes that is correct; all else being equal, a binocular with half transmission is *indeed* half as good as one with perfect brightness. I would personally not even consider a 50% binocular no matter how perfect it is otherwise (so even half way in the scoring is already generous).

MagpieCorvidae said:

Fifty percent transmission is a significant optical deficiency. So, yes that is correct; all else being equal, a binocular with half transmission is *indeed* half as good as one with perfect brightness. I would personally not even consider a 50% binocular no matter how perfect it is otherwise (so even half way in the scoring is already generous).

Click to expand...

I thinks you be missing the point he is making.

eitanaltman said:

I've done a similar thing before, but I think if you are trying to isolate optical metrics you can't leave out the internal reflections and FOV scores. Glare control / blackening and FOV are pretty important aspects of optics.

It definitely does get interesting if you exclude the exit pupil truncation and especially the ridiculous IPD scores.

Click to expand...

And there are ways to test for that...
I'm thinking "huh, what about measuring contrast and black level???"

Transmission means little nowadays. They are all so good. T at the top is 10 yrs out of season.
Contrast is far more important than brightness, information/cortex-wise.

Weighted average with your priority items having the greatest weight...

As everyone's priorities are different, everyone's results are going to be different.

Helps explain the disagreement and lack of consensus on this forum.

I would like to see "resolution at center of field", and for my own comparison I would include "ergonomics" which would be heavily weighted.

I also agree that internal reflections or lack of can make or break a binocular.

CG

MagpieCorvidae said:

Fifty percent transmission is a significant optical deficiency. So, yes that is correct; all else being equal, a binocular with half transmission is *indeed* half as good as one with perfect brightness. I would personally not even consider a 50% binocular no matter how perfect it is otherwise (so even half way in the scoring is already generous).

Click to expand...

Wait, so now you're bringing in your subjective opinion, while this was meant to be an objective ranking. Weighted averages are fine, but you are now weighting them based upon your own personal opinion, as opposed to creating a generalized model for ranking binoculars.

I've alwo wondered why allbinos doesn't measure sharpness/resolution of the centerfield - maybe like the other more analytical bino reviewer (Holger?) often states, they believe them to all be so sharp and capable of resolving to a level that our eyes couldn't perceive the minute differences, so it is not worth reporting upon.