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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)

… and the same glass, same AR coatings, similar craftsmanship on the prisms, etc etc - looks like a challenge:unsure:
I think we therefore just have to believe if someone says he or she can see a difference in contrast between S-P and AK (I don‘t, and I have a hard time believing :))
There is a crispness and sparkle in my HT's that just isnt quite there on the non AK's i've owned.
I would describe it as crystal clear, very bright.
I adore Leics HD+ and also my old Meostars, but they are more coloured, richer, and non the worse for it, just different.
But the first time I looked through HT's they just popped like no other bino I have looked through.
The bank card came out shortly after, and I wasn't really looking to buy that day.
But I also know I could live with a pair of Leica HD+ no problems whatsoever, or Swaro SLC's.
They are all so good, but I do think I could tell an AK from a SP.
 
There is a crispness and sparkle in my HT's that just isnt quite there on the non AK's i've owned.
I would describe it as crystal clear, very bright.
I adore Leics HD+ and also my old Meostars, but they are more coloured, richer, and non the worse for it, just different.
But the first time I looked through HT's they just popped like no other bino I have looked through.
The bank card came out shortly after, and I wasn't really looking to buy that day.
But I also know I could live with a pair of Leica HD+ no problems whatsoever, or Swaro SLC's.
They are all so good, but I do think I could tell an AK from a SP.
Hear, hear. I see the same thing in my Zeiss FL 7x42's. The AK prism seems to be crystal clear and very bright. That was the reason I started this thread. Maybe it is the AK prism creating the difference I am seeing.
 
There is a crispness and sparkle in my HT's that just isnt quite there on the non AK's i've owned.
I would describe it as crystal clear, very bright.
Just to be contrarian though - one could attribute it to the very high transmission the HT was designed to achieve (apparently 95%) in which the prisms do play a part, but so do other factors - glass types, coatings etc. They are very bright, no doubt about that. Would you say you see the same "crispness" etc in other Abbe-Koening binoculars you've owned (and what were they)?
 
Just to be contrarian though - one could attribute it to the very high transmission the HT was designed to achieve (apparently 95%) in which the prisms do play a part, but so do other factors - glass types, coatings etc. They are very bright, no doubt about that. Would you say you see the same "crispness" etc in other Abbe-Koening binoculars you've owned (and what were they)?
Yes.... Zeiss FL 8x56
Same sort of effect.

When my friend, who bought my old Conquests off me, picked up my HT's, his words....

'Its like an assault on the senses'

Which made me laugh, but I kinda get it(y)
 
yes, I think we will see differences even where we shouldn't see them. :ROFLMAO: When two identical binoculars are presented to us as different, the psychological effect tells us that there must be a small difference...
That's a very interesting point.

When we are told there's a difference ..... we will find one.

Sounds like another subjective "test" and just another "What do you see?" question.

Thinking about it, I would suspect that this effect would have been investigated by psychologists, and there must be something in the literature.
 
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Just to be contrarian though - one could attribute it to the very high transmission the HT was designed to achieve (apparently 95%) in which the prisms do play a part, but so do other factors - glass types, coatings etc. They are very bright, no doubt about that. Would you say you see the same "crispness" etc in other Abbe-Koening binoculars you've owned (and what were they)?
I think you have a point here. Surely the AK prisms make a difference because they increase transmission about 2%, but the HT glass does also. So the sparkle probably comes from the combination of the two working together.
 
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the pop of the abbe prism mostly comes from additional length between objective lenses which occurred by shape of prism.

same as porro prism gain the 3D effect but much less.
I love AK Prism style 3D because 3D of porro prism get me easily tired especially at close distance observation.

but nothing more specific then bit of 3D effect and higer transmission.

maybe can enhance contrast a bit which can be additional advantage in resolution.

still, Swarovski NL, EL which using SP prism is sharper then AK ones above.
 

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the pop of the abbe prism mostly comes from additional length between objective lenses which occurred by shape of prism.

same as porro prism gain the 3D effect but much less.
I love AK Prism style 3D because 3D of porro prism get me easily tired especially at close distance observation.

but nothing more specific then bit of 3D effect and higer transmission.

maybe can enhance contrast a bit which can be additional advantage in resolution.

still, Swarovski NL, EL which using SP prism is sharper then AK ones above.
Thanks for that, Jackjack! You're correct. I forgot about the additional objective spacing an AK prism binocular has, which creates the 3D effect. Porro prisms aren't real good at close distance, as you say. I really notice the 3D effect in my Zeiss FL 7x42's because of the AK prism, and I think there is an increase in contrast and resolution because of it. Rg548 is probably seeing similar things in his HT 8x42, plus it has the advantage of very high transmission. Nice pictures by the way! It really shows the difference in objective spacing between an AK prism binocular and an SP Prism binocular.
 
Hi jackjack (post #247),

'the pop of the abbe prism mostly comes from additional length between objective lenses which occurred by shape of prism'

Could you explain why that is so?

And if the pop of A-K prism binoculars is due to their small amount of objective offset when compared to S-P prism ones
- then why is the pop not much more with regular Porro prism binoculars, with their far larger offset?


John


By way of comparison:
To give an idea of the amounts of objective offset possible for different prisms and binocular types:

A) John/ Tringa 45 has previously provided measurements for the following roof prism models,
in post #6 at: [Tech] Are most/all roof binocular oculars and objectives collinear?
Using an IPD setting of 63 mm:
Swarovski SLC 7x42, 2 mm
Swarovski EL SV 10x42, 5 mm
Meopta B1 7x42, 6 mm

Swarovski SLC 8x56, 15 mm (Abbe-Koenig prism)


B) From Leica (IPD unstated):
Geovid Rangefinder x42, 14mm (Perger prism)


C) And from me, using an IPD setting of 63 mm:
Swarovski EL SV 12x50, 9 mm

And some Porros:
Swarovski Habicht 10x40, 57 mm (also Habicht 8x30)
Nikon E 12x40, 63 mm (also E 8x30)
Nikon E II 10x35, 63 mm (also EII 8x30)

- -
So hopefully someone with a Canon 10x42 can provide a measurement for comparison.

- - - -
As can be seen, there's significant differences between:
• what's possible in moderate sized Schmidt-Pechan prism binoculars (2 to 6 mm);
• larger Abe-Koenig prism binoculars (at least 15 mm), and;
• regular configuration Porro prism binoculars (60 mm +/-) . . .
. . . the optical axis separation between the two objectives in the 10x42 L is 70 mm, which means that it gives a stereo base equal to bare eyes for people with 70 mm IPD, and slightly reduced stereopsis for those with larger IPDs and slightly enhanced stereopsis for people with smaller IPD's . . .

Kimmo
 
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Jhon,
Not all of us have the same sensitivity to 3d. For those with good stereoscopic vision, binoculars with porro prisms have this 3d effect much more pronounced than a bino with Abbe Koenig (AB) prisms. In the same way, those with good stereoscopic vision even can notice the difference between two roof Shmidt Pechan (SP) prisms binoculars if one has the objectives a little further apart.
There are tests for 3d sensitivity
Why Test for 3D Vision?
 
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Hi dorubird,

I take your point.

However, the immediate prior discussion was largely about the 'pop' when viewing through binoculars with A-K prisms vs S-P ones
i.e. the superior image quality that many perceive with the former.
And that would likely be due to the A-K prisms themselves:
a more relaxed construction (4 reflections vs 6);
no non-Total Internal Reflection surface, so no need for a dielectric surface coating (unlike S-P prisms), and;
no combined reflection/ transmission surfaces (of which S-P prisms have 3) *

In contrast, what jackjack seems to be saying (?) is that the pop of A-K prism binoculars, is primarily due to the slight objective separation
of the binoculars - rather than any intrinsic advantage of A-K prisms over S-P ones.
Hence my query.


John


* For more see post #2 at: Roof Prisms Used in Binoculars
And a set of images comparing A-K, S-P and Uppendahl prisms is in post #3 at: Dielectric Coatings - Potential Drawbacks?
 
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Hi jackjack (post #247),

'the pop of the abbe prism mostly comes from additional length between objective lenses which occurred by shape of prism'

Could you explain why that is so?

And if the pop of A-K prism binoculars is due to their small amount of objective offset when compared to S-P prism ones
- then why is the pop not much more with regular Porro prism binoculars, with their far larger offset?


John


By way of comparison:
the mean
same as porro prism gain their 3D but much less is

AK prism gain 3D because of the spaces between objectivelenses similar to porro prism.
but less then porro prism.

thats why I wrote that I prefer 3D of AK because it is weaker then Porro so give me bit more relaxing view but bit more 3D then normal SP roof prisms.
 
How did you test the binoculars for sharpness? Your workings and results would be very interesting.

Andy
many.
hand held + tripod,
under 100m / 50m / 25m / 10m

if with booster 6 ~ 8 power, under 200 ~ 50m

mainly objects with straight lines. such as resoultion chart, handrail, telephone pole, brick wall, QR code...extra


10x42

NV < HT < SF < NL < EL

8x42

EDG < SF < NV < HT < NL < EL (8.5)

8x30 ~ 32mm

CL Companion = MHG < UV HD, HD+ < Conquest HD < SFL < T*FL < NL < ELSV (fieldpro) < ELSV (pre fieldpro)
 
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How did you test the binoculars for sharpness? Your workings and results would be very interesting.

Andy
I was going to pick up on this....

My HT's are razor sharp, as good as I've ever seen, or I wouldn't have bought them.
I know Swaros, and Leicas are also exemplary, and I'm not entirely convinced that the human eye can differentiate between the 'alpha' binos with regard to sharpness.
The claim that the swaro's are sharper than HT's.... well i'm not convinced, and if you have to use charts and further magnification to prove it, you are arguing over what the eye cannot see...... if that makes sense.

I've not seen 'sharper' than my HT's.... but i'm sure other top tier binos are as sharp.
But it doesn't take away from the 'clean, bright, sparkle' that I have only seen in AK's.
It is a different look, not necessarily better, just an alternative for us to enjoy, and I for one still love Leica's, and their viewing experience, and they are obviously not AK's.

You also have to remember that AK's were around for good reason.
For those happy to compromise on the weight, and size.... and expense.... and in their prime, the gap between AK's and SP was much more than it is today.
95-96% transmission says it all, if that is on your list of priorities in a bino!!
 
many.
hand held + tripod,
under 100m / 50m / 25m / 10m

if with booster 6 ~ 8 power, under 200 ~ 50m

mainly objects with straight lines. such as resoultion chart, handrail, telephone pole, brick wall, QR code...extra


10x42

NV < HT < SF < NL < EL

8x42

EDG < SF < NV < HT < NL < EL (8.5)

8x30 ~ 32mm

CL Companion = MHG < UV HD, HD+ < Conquest HD < SFL < T*FL < NL < ELSV (fieldpro) < ELSV (pre fieldpro)
It is interesting that you consider the EL(pre fieldpro) sharper than the EL(fieldpro). I wonder what would make the difference. So out of all the 10x42 alpha's the Noctivid is the least sharp of the bunch and the EDG is the least sharp out of the 8x42 alphas? Thanks, for the testing! Very interesting!
 
I was going to pick up on this....

My HT's are razor sharp, as good as I've ever seen, or I wouldn't have bought them.
I know Swaros, and Leicas are also exemplary, and I'm not entirely convinced that the human eye can differentiate between the 'alpha' binos with regard to sharpness.
The claim that the swaro's are sharper than HT's.... well i'm not convinced, and if you have to use charts and further magnification to prove it, you are arguing over what the eye cannot see...... if that makes sense.

I've not seen 'sharper' than my HT's.... but i'm sure other top tier binos are as sharp.
But it doesn't take away from the 'clean, bright, sparkle' that I have only seen in AK's.
It is a different look, not necessarily better, just an alternative for us to enjoy, and I for one still love Leica's, and their viewing experience, and they are obviously not AK's.

You also have to remember that AK's were around for good reason.
For those happy to compromise on the weight, and size.... and expense.... and in their prime, the gap between AK's and SP was much more than it is today.
95-96% transmission says it all, if that is on your list of priorities in a bino!!
Those HT's have that clean, bright sparkle because of the 95% transmission and AK prisms. I have found binoculars with high transmissions like the HT to have a lot of sparkle in the daytime. The Habicht porros are the same way. My HT 8x54 had that clean, transparent sparkle also.
 
It is interesting that you consider the EL(pre fieldpro) sharper than the EL(fieldpro). I wonder what would make the difference. So out of all the 10x42 alpha's the Noctivid is the least sharp of the bunch and the EDG is the least sharp out of the 8x42 alphas? Thanks, for the testing! Very interesting!
haven't seen 10x42 EDG yet

EDG is the hand down best at comfort of the view but brightness and central sharpness can't compete with the 8x42 list I posted.

NV 10x42 falls lot in terms of colorfidelity, sharpness then 8x42 NV.
but I personally prefer lieca style amber contrast of 10x42 NV more


directly compared 8x32 EL SV fieledpro(new) and new field pro.

new has better color satuation but brightness and sharpness is superior in old SV

old 8x32 ELSV is sharpest 8 power bino I have seen yet.
(have compared it directly with almost every top 8 power in market. such as Razor UHD, opticron aurora, MHG 30/42, EDG 42, E2, CHD, TFL, HT, SF, SFL, UV, NV, New el, NL)

also heard about 8.5x42 new / old are similar.
 
I'll pile on by saying that I think if you need 30X to see a difference between two binoculars, or the two tubes of a single binocular, that difference is insignificant and undetectable.

Fun, but insignificant.
yes. but the difference I posted can be seen in 1x magnification. boosters are for double checking it by enlarging the tiny difference.
 
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