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Where premium quality meets exceptional value. ZEISS Conquest HDX.

Why are Zeiss so sharp on-axis compared to other binoculars? (1 Viewer)

Henry’s boosted testing (actual testing) of his two FLs did find very high resolution….now whether or not he’s tested others that scored higher would be for Henry to say.

There are a few aspects of my SF that don’t wow me, such as colour contrast, but they do have remarkable (apparent) micro contrast.
 
The Zeiss SF 8x32 is the best CA result at 9.4 in the history of Allbinos testing, and the Zeiss FL 8x32 with a CA result of 9.2 is the 2nd best!

Find a binocular with a better CA score.

I test all my binoculars for CA with a similar method to Allbinos and I agree with their results.
then I have to wonder why they state the SF is “one of the best” instead of the “very best” of their results? maybe because they’ve forgotten what scores they gave the FL since it was tested so long ago! Is it even the same people testing from year to year? Anyway I don’t put any stock into their ratings. I do like reading their reviews sometimes though.
 
What are your methods for measuring longitudinal and lateral CA?

While you're at it how about spherical aberration and astigmatism?
I test all my binoculars with a method similar to the one Allbinos uses for CA. I have tested about 100 binoculars this way, and the Zeiss SF 10x32 had the lowest CA I have ever seen, followed closely by the Zeiss FL 8x32. Likewise, I agree closely with Allbinos results. This is Allbinos method.

"CHROMATIC ABERRATION (10 points) - The chromatic aberration is estimated by our own observations, setting a contrastive object in the center of the field of view and moving it to the corner. Depending on our observations, binoculars can get here from 0 to 8 points for the center performance and -/+ 2 points for behavior at the edge."
 
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no, they said it has ‘one of the best’ results …

“Add to that a sensationally corrected astigmatism, distortion and coma. Also chromatic aberration correction result, one of the best in the whole history of our tests, is achieved despite such a wide field of view. If you don't like CA effects, the Victory SF 8x32 is definitely your pair of binoculars because it fares distinctly better than all binoculars produced by its main rival, Swarovski. Swarovski binoculars have noticeable problems with chromatic aberration on the edge of the field which is often narrower than the field of the Zeiss”
The Zeiss SF 8x32 scored 9.4 on CA which was the highest score ever for CA control on Allbinos and the Zeiss FL 8x32 scored 9.2 for CA which was 2nd highest score.
 
My theory on why Zeiss SF and FL seem so sharp on axis is because they have the lowest CA of any binoculars and I believe low CA leads to higher resolution because all the different spectrum of light converge into one point on the optical axis making them appear sharper. Here are some charts on CA demonstrating what I mean.

"Chromatic aberration negatively affects image quality by causing color fringing, particularly at high-contrast edges. Moreover, it can distort the image by blurring some of its regions and reducing overall sharpness. This leads to a decrease in image detail and clarity."


Schematic-diagrams-presenting-the-two-forms-of-chromatic-aberration-a-longitudinal.jpgChromatic_aberration_(comparison).jpgsensors-17-01048-g001.png
 
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My theory on why Zeiss SF and FL seem so sharp on axis is because they have the lowest CA of any binoculars and I believe low CA leads to higher resolution because all the different spectrum of light converge into one point on the optical axis making them appear sharper. Here are some charts on CA demonstrating what I mean.

"Chromatic aberration negatively affects image quality by causing color fringing, particularly at high-contrast edges. Moreover, it can distort the image by blurring some of its regions and reducing overall sharpness. This leads to a decrease in image detail and clarity."


View attachment 1596952View attachment 1596959View attachment 1596961
Very nice pictures and diagrams, I like it. But how many are agreeing with you that the Zeiss is sharper on axis than Swarovski or Leica (Noctivids), I’m certainly not. I don’t think my 8x32 SF is sharper than my EL’s, NL’s, or the SF 42 I’ve compared with Noctivids. I might be wrong , but I think that physiology or personal preference at these optical levels play more of a roll than the diagrams.
 
Do you notice a difference in CA between your binoculars, or is it not something you notice? Not everybody sees CA until it is pointed out to them. Are you Noctivids 8x42 still your favorite overall binoculars?
I’m sensitive to CA and glare, but not overly sensitive to either. I see glare and CA in all binoculars under specific conditions. I see more CA in Noctivids than SF’s or EL’s, but there is no CA in the center 90% of my observing sessions in 8x42 Noctivids. I do think they’re my favorite 8x42’s. There’s nothing sharper than a Noctivid imo.
The Zeiss especially the SF and FL just seem sharper to me on-axis for some reason. Even the Zeiss Conquest HD 8x32 seems to me to be one of the sharpest binoculars on-axis at the $1000 price point.
The Conquest’s are very sharp, I might agree they’re one of the sharpest in the genre. Let me clarify, I’m not saying the SF or FL’s are not some of the sharpest available, I just don’t think they’re any sharper than an EL or the Habicht.
 
Blah blah, old hat

Currently the Swarovski NL series are probably the best birding binoculars.

If I were selling my dozen bins and starting a collection from scratch I'd start by buying three or four NL.
Certainly a nice new 8x42 NL rather than a 7x42FL
😄
 
The Zeiss especially the SF and FL just seem sharper to me on-axis for some reason.
That's an accurate description of what you actually know so far.

Simple objective test methods are available to you that could support (or falsify) and explain your "just seems sharper..for some reason" impressions. Why don't you use them?

And please stop misappropriating, distorting and over-simplifying old material of mine to prop up your "theories".
 
After 185 post, I think that we explored the topic a lot. We will not gain more information, by just discussing and referencing others reviews.

What we can expect, that allbinos does good reviews. Maybe there test methods are not 100% perfect but they are a good indicator. I think they do it as objective as possible.

It‘s unlikely that someone of the forum members would have all the binos we discussed here, to make proper resolution and CA comparisons. It would be a guy with a lot of high quality binos but with around 10-20k less money. Because they are all pricey. 😂
 
You can read all the reviews and opinions ever written or posted, but not one of them can tell you what you will see, using your eyes and your brain to process the signals from your eyes.

If you want to choose a binocular, look through it.
That is my take on it too..... even after reading and digesting trusted reviewers and sorting the BS from the actual.

You can only truly decide by using your own Mk1 eyeballs.
 

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