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Zeiss Conquest 10X42 HD-AllBinos Review (1 Viewer)

Sure, let's go with that. Overwhelmingly, the consensus is that the HD looks sharp due to poor eyesight of an overwhelming number of individuals.

Makes perfect sense.

James,

I'm glad you now understand the crux of the issue.:t: ;);)

Seriously though, this is something the industry needs to sort out. The ISO standard all of the big companies did allow 'high quality' binoculars to have a full objective resolution that is roughly 2 fold worse than the diffraction limit. If most of that aberration is confined to the peripery of the objective that wouldn't be much of a problem, as that is blocked by the iris of the eye in bright viewing conditions. However if the aberrations were more uniformly distributed then it means that those with 20/15 vision should be able to pick up the problem with poorer samples. You would probably need to be 20/12 or better for the worst of those samples I saw. That's less than 10% of the population. I've now tested a few £200 binoculars that would match the premium models for effective resolution and easily beat those Conquests I tried..

I did discuss the problem with one of the senior people at Zeiss a couple of years ago and he assured me they would be developing a new QC protocol, but I don't know if that would cover their binoculars made by third parties.

The ISO standard was revised earlier this year. Bizarrely for 8 and 10x42s the "high quality" limit was actually relaxed to 2.5 times worse than the diffraction limit. Expect more dodgy binoculars in the future.

David
 
Posting this was held back for a couple of hours to see if David had responded and now he has.

The difference, sometimes even polarization, of opinion about some model of binocular in this forum has long puzzled me. A few times it has kept me from buying some model that was initially rated very highly here (I use this forum for guidance). The Zeiss Conquest HD 8x32 is a current example!

It may be that there are several factors. These may be visual acuity; cataract, or glaucoma, in whatever degree; astigmatism (in the observer's vision), RG color blindness in whatever degree, max. pupil diameter in low light, and other, possibly age-related, conditions (that I am not familiar with). Some people do not like mentioning these matters in relation to themselves, another such being age. (This may be for two opposite reasons, modesty being one!)

I would think that if they are set out in each review or report, in some manner, where the reviewer does not mind doing so, a good deal if not all of this variation will be explained, argument will be at a minimum, and a third-party reader will be able to make a better assessment. Otherwise there will continue to be argument arising from dialog at cross purposes.

Most people do not even know what their visual acuity is or their pupil dilation. These are not usually found in reports by opticians. (They cannot be altered by glasses etc.) Of course, the reader who assesses has also to know these things about him/herself!

The Cornell tests, much discussed here a few years back, averaged the assessments of a large number of users (gathered for the purpose), on a few broad criteria easily understood by any user, and rated several models of the current Conquest line at the highest level optically. It may be that the visual acuity, and/or maybe some other relevant factor, in those who see a lapse in the optical quality of this line, is unusually good, and found only in a minority of people worldwide.
 
"Most people do not even know what their visual acuity is or their pupil dilation. These are not usually found in reports by opticians. (They cannot be altered by glasses etc.) Of course, the reader who assesses has also to know these things about him/herself!"

Yesterday i had a retinopothy check which required dilation of the pupils. I asked the technician to measure my dilated pupils but she would not do this because she did no have the means. She told me that maximimum dilation occurs two hours after inserting the eye drops. Later, at home, my wife checked for me and her estimate was that both diameters were about 7mm.

What diameter might I expect my pupils to be at twilight (Dammerung)?
 
I haven't been able to find out how the diameters for atropine induced pupil dilation differs from normal dark adaption but 7mm sounds pretty good. The papers I tracked down a few years ago suggested the average for a 60 year old was 5 to 5.5mm but there was quite a spread, from over to 7 to under 4mm if I remember rightly.

David
 
The Cornell tests, much discussed here a few years back, averaged the assessments of a large number of users (gathered for the purpose), on a few broad criteria easily understood by any user, and rated several models of the current Conquest line at the highest level optically. It may be that the visual acuity, and/or maybe some other relevant factor, in those who see a lapse in the optical quality of this line, is unusually good, and found only in a minority of people worldwide.

That would be a significant minority. In one study of university students I've read around 20% reached the 20/12 criteria I suggested for spotting those Conquest HD deficiencies, but that percentage does drop with age.

That Connell study does illustrate how misleading results can be if you average a minority who can see a difference with a majority who can't. You might be forgiven for thinking that the Swaro CL was actually any good. ;)

David
 
That would be a significant minority. In one study of university students I've read around 20% reached the 20/12 criteria I suggested for spotting those Conquest HD deficiencies, but that percentage does drop with age.

That Connell study does illustrate how misleading results can be if you average a minority who can see a difference with a majority who can't. You might be forgiven for thinking that the Swaro CL was actually any good. ;)

David

Hi David,

Let me know if I'm following this correctly or not...I do get lost frequently
when you touch on visual acuity, eye issues and behavior, etc. (which is often).

It seems like the gist of the argument is that reports of subpar resolution or sharpness (and you have pointed out there is a difference in other posts) in the case of the Conquest HD must be (or could be?) coming from people with above average eyesight with no eye issues. But, we don't know the visual acuity or eye health of any reviewer, so it seems we are making assumptions here.

My rule of thumb when reading reports/reviews of any binocular is to look at the general consensus; if a bino receives a vast majority of positive reviews , in the case of the Conquest HD, then I tend to think it's pretty good until of course I try it myself which is the most important thing since I'm stuck with my own eyes (good or bad). Couldn't some of these positive reviewers have good vision with no eye issues (such as glaucoma etc) ? Why do we assume that reports of poor sharpness are by people with above average vision with no eye health conditions ? Couldn't one or two of these reviewers have poor vision and this is why the subpar performance report of the Conquest HD?

I'm not saying this is the case, but only reminding us that we don't know the vision of any reviewer or tester since this is not mentioned; it's usually mentioned if someone wears glasses or not which still doesn't tell us much.

Are you positing the following?:
Since a small amount of the population have above average eyesight and Conquest HD has reports by a small amount of people (of subpar resolution), then these reports may be coming from the only people with the ability to see the flaws of the bin.
If the above is what you are suggesting then IMO it jumps to conclusions.

Let me know if I'm reading all of this the wrong way. I always respect your opinions and depth of knowledge.
 
Did someone call? :-O

Lee,

Not in my book. It simply says to me he thinks they are wrong.
This is what you posted at the time:
"Best Value: Conquest HD 8x32 then in second place Terra ED 8x42 ......."

Sorry Lee, I didn't think they were as good as you made out. ;)

Cheers,

David

Hya David

Checked out with a few local folks and here in South Yorkshire to 'make out' = to 'make up'. So maybe its a Yorkshire thing.
Storms, small tea-cups, etc.

Lee
 
GG,

I hope I've made it clear all along that I accept there is sample variation and individual samples may be very good. I just noted when I compared several Conquest HDs toTerras and HTs I saw differences in apparent resolution that I thought surprising and disappointing for the price. I have tried others since and some were better than others to my eyes.

What I do know is that from doing a lot of resolution testing and self acuity testing is exactly how good an effective resolution has to be to exceed my visual acuity. It is exactly my acuity divided by the magnification. This rule will apply to every user. For an 8x binocular, 20/20 will be 15 arcseconds, 20/15 11.25 arcseconds, 20/12 9 arcseconds and for 20/10 7.5 arcseconds.

To ensure a binocular satisfies all users it needs to have an effective resolution better than 7.5 arcseconds.

In my estimation, from those original Conquest HDs I tried, one was over 10 arcseconds, another around 9.5 and a couple around 8.5 arcseconds. The last couple were better than 8" but I suspect not as good as 7". When you consider that my ZR Prime is 6.8", my Vanguard Endeavour EDII 6.4" and the Kite Bonelli 2 I reviewed 5.8". Even a cheap Hawke Endeavour ED 8x32 I reviewed was 6.8". I hope you will understand those Conquest figures look poor but you will need better than average eyesight to see it.

If a £200 binoculars can beat the 7.5" threshold, then shouldn't we expect a £650 to do so, whether the average user can spot it or not?

David
 
GG,

I hope I've made it clear all along that I accept there is sample variation and individual samples may be very good. I just noted when I compared several Conquest HDs toTerras and HTs I saw differences in apparent resolution that I thought surprising and disappointing for the price. I have tried others since and some were better than others to my eyes.

What I do know is that from doing a lot of resolution testing and self acuity testing is exactly how good an effective resolution has to be to exceed my visual acuity. It is exactly my acuity divided by the magnification. This rule will apply to every user. For an 8x binocular, 20/20 will be 15 arcseconds, 20/15 11.25 arcseconds, 20/12 9 arcseconds and for 20/10 7.5 arcseconds.

To ensure a binocular satisfies all users it needs to have an effective resolution better than 7.5 arcseconds.

In my estimation, from those original Conquest HDs I tried, one was over 10 arcseconds, another around 9.5 and a couple around 8.5 arcseconds. The last couple were better than 8" but I suspect not as good as 7". When you consider that my ZR Prime is 6.8", my Vanguard Endeavour EDII 6.4" and the Kite Bonelli 2 I reviewed 5.8". Even a cheap Hawke Endeavour ED 8x32 I reviewed was 6.8". I hope you will understand those Conquest figures look poor but you will need better than average eyesight to see it.

If a £200 binoculars can beat the 7.5" threshold, then shouldn't we expect a £650 to do so, whether the average user can spot it or not?

David

David,

Where can we blame this on?
Collimation, lens defects?

Jan
 
GG,

I hope I've made it clear all along that I accept there is sample variation and individual samples may be very good. I just noted when I compared several Conquest HDs toTerras and HTs I saw differences in apparent resolution that I thought surprising and disappointing for the price. I have tried others since and some were better than others to my eyes.

What I do know is that from doing a lot of resolution testing and self acuity testing is exactly how good an effective resolution has to be to exceed my visual acuity. It is exactly my acuity divided by the magnification. This rule will apply to every user. For an 8x binocular, 20/20 will be 15 arcseconds, 20/15 11.25 arcseconds, 20/12 9 arcseconds and for 20/10 7.5 arcseconds.

To ensure a binocular satisfies all users it needs to have an effective resolution better than 7.5 arcseconds.

In my estimation, from those original Conquest HDs I tried, one was over 10 arcseconds, another around 9.5 and a couple around 8.5 arcseconds. The last couple were better than 8" but I suspect not as good as 7". When you consider that my ZR Prime is 6.8", my Vanguard Endeavour EDII 6.4" and the Kite Bonelli 2 I reviewed 5.8". Even a cheap Hawke Endeavour ED 8x32 I reviewed was 6.8". I hope you will understand those Conquest figures look poor but you will need better than average eyesight to see it.

If a £200 binoculars can beat the 7.5" threshold, then shouldn't we expect a £650 to do so, whether the average user can spot it or not?

David

Thanks for the explanation David and this is all a learning process for me.
I may have missed it in another thread, but I'm assuming that you have above average eyesight , better than 20/20 in order to gauge or estimate a given sample's effective resolution like that.

I'm guessing my eyes with spectacles gives me 20/20 if the prescription is correct at this point in time.

Just got out of the shower and re-read my previous post and want to make sure I didn't come off argumentative with you. I was just trying to figure what you were getting at. Conquest HD looked nice the few brief times I looked through it at the store, but I don't own it and certainly not "taking sides" here in any way.
I thought the view was maybe slightly warm and had very nice contrast. I like the 8x32 and didn't get along much with the bigger bins in terms of fit in hand.
 
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David,

Where can we blame this on?
Collimation, lens defects?

Jan

Jan,

I think it's more than a coincidence that the second (or third) tier models from the big three appear to fail to meet the effective resolution standards of their flagship models. (Though there appeared to be a short lived version of the ELSV 8.5x42 that didn't look so good). It seems to offer at least the possibility that by design, and/or specification they were not intended to directly compete by this measure. Makes commercial sense to me at least. Fortunately the competition don't appear to feel the same constraints. It's clearly within the capabilities of OEMs like Kamakura to produce models to a higher resolution standard than used even for the flagship models. The Opticron Aurora and the Kite Bonelli 2 are two fine examples. Why would Zeiss wan't that for a cheaper model?

David
 
David

And is 'effective resolution' different from 'resolution'?

Lee

Yes, it's the resolution for the diameter of the objective corresponding to your pupil diameter. rather than the instrument resolution. Optimum visual acuity usually corresponds to a 2.5mm pupil diameter. For an 8x I would measure the resolution for a 2.5x8= 25mm centre area of the objective.

David
 
Yes, it's the resolution for the diameter of the objective corresponding to your pupil diameter. rather than the instrument resolution. Optimum visual acuity usually corresponds to a 2.5mm pupil diameter. For an 8x I would measure the resolution for a 2.5x8= 25mm centre area of the objective.

David

Thanks David and of course we have been here before with your proposals for stopped-down testing.

Lee
 
Jan,

I think it's more than a coincidence that the second (or third) tier models from the big three appear to fail to meet the effective resolution standards of their flagship models. (Though there appeared to be a short lived version of the ELSV 8.5x42 that didn't look so good). It seems to offer at least the possibility that by design, and/or specification they were not intended to directly compete by this measure. Makes commercial sense to me at least. Fortunately the competition don't appear to feel the same constraints. It's clearly within the capabilities of OEMs like Kamakura to produce models to a higher resolution standard than used even for the flagship models. The Opticron Aurora and the Kite Bonelli 2 are two fine examples. Why would Zeiss wan't that for a cheaper model?

David

OK, to keep it within my restricted limits of understanding;

Recently I visited a plant and they showed me how QC was conducted.
They placed a model on a collimater and the screen had a space of 20 by 20 cm. If both barrels were within that space it was OK. Upper left or right, as long as long as it was in that square it was within their perimeters.

So I asked them, if this is your top gun model why not everything exactly right in the center. It is perfect or not and your second tier model may have those 20cm space.

I only heard a "No" and no further explanation.

Is, what you describe with that arc seconds...etc, a direct consequence of "lack" of precision collimation?

Jan
 
OK, to keep it within my restricted limits of understanding;

Recently I visited a plant and they showed me how QC was conducted.
They placed a model on a collimater and the screen had a space of 20 by 20 cm. If both barrels were within that space it was OK. Upper left or right, as long as long as it was in that square it was within their perimeters.

So I asked them, if this is your top gun model why not everything exactly right in the center. It is perfect or not and your second tier model may have those 20cm space.

I only heard a "No" and no further explanation.

Is, what you describe with that arc seconds...etc, a direct consequence of "lack" of precision collimation?

Jan

Jan,

Collimation just makes sure the tubes are fairly close to parallel. Confusingly that would also be measured as an angle.

Resolution would be done on quite a different instrument though is superficially might look similar. It is essentially a camera with a high quality long lens which is used to determine the limit of detail a binocular is capable of showing. The computerised method used in a commercial lab actually measures something called the modulation transfer function. This a page for a popular analytical package and the MTF plot is at the bottom.
http://www.imatest.com/docs/sharpness/

All you really need to understand is it produces pretty much the same answers as a line chart. The diffraction limit for a 42mm objective is about 2.8 arcseconds. The old ISO requirement for high quality binoculars was they should be better than 5.8 arcseconds and the design standard for something like a HT or SF would be 4.5 arcseconds, but they would specify each sample should be better than 5.2 arcseconds. Chinese OEMs obviously use the same kind of standard.

The optical designer is able specify the optical accuracy and aberration distribution of every lens in the light path to achieve that standard. The consequence is the potential to produce a broad range of effective resolution and contrast performance which can be used as a quality differentiator. The ELSV 8x32 and the CL 8x30 would be a reasonable illustration.

The Opticron Aurora was specified to be less than 4 arcseconds and the Kite Bonelli seems better still.

David
 
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Jan,

Just a further comment on collimation.

I know someone here posted a military or ISO standard for collimation at one time and I think it was probably Bill who said it wasn't good enough. (Well I think that was the gist of it. ;) )

I have tried a back yard method I found online for testing collimation and it looked like most of the models I have were a degree or two out, but I couldn't spot it by eye. The exception was two binoculars that arrived in a very badly damaged carton. By eye, one had a vertical displacement of I'd guess about 3% of the field diameter and the other just over 5%. Neither made any difference at all to the appearance of stars or impaired performance in a chart test in any way.

I seems likely that we do differ in our tollerance of collimation error, and it's good there is a manufacturing standard for it, but for me at least, it appears to be one of the least critical parameters in a binocular's performance. I'm sure Bill would vehemently disagree.

David
 
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David,

That's very interesting, particularly since the one issue that probably causes more headaches than any other is collimation. At least that's been my experience.

Are you poo-pooing the limits specified in the SPIE Field Guide to Binoculars and Scopes? It seems like you're talking about at least an order of magnitude difference.

Ed
 

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Lee, you're clutching at more straws than Ricky Ponting trying to imitate a half way decent Captain!

Chosun :gh:

CJ

An interested bystander sent me a link to this definition in the Cambridge University on-line dictionary:

make out informal — phrasal verb with make:​

to say, usually falsely, that something is true [/I]​


Or to put it another way, to make something out is to make something up.

Jess Ennis-Hill begins her defence of her pentathlon title today! And Ricky Ponting wasn't that bad, surely?

Lee
 
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