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Bird Watching magazine reviews

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Old Tuesday 6th January 2004, 21:12   #1
Leif
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Bird Watching magazine reviews

I've decided that I'll get a nice scope this year so I've been looking at reviews in back issues of BW magazine. Anyway, what surprises me most is the inconsistency. Here are some results for optics:

In 2003 survey:

Leica APO 62 optics = 9.5
Swaro APO 66 optics = 9.5
Zeiss diascope 65 optics = 9.0
Opticron HR 66 ED optics = 8.0
Kowa 663 ED optics = 7

In 2002 survey:

Leica APO 62 optics = 9.5
Swaro APO 66 optics = 9.5
Zeiss diascope 65 optics = 8.5
Opticron HR 66 ED optics = 9.0
Kowa 663 ED optics = 9.5

What worries me is that in 2002 the Kowa and Opticron scopes optics were rated very highly whereas in 2003 they both scored sunstantially less, with the Kowa considered as mediocre. Another example is the Nikon 78mm scope with zoom eyepice which in 2002 was rated by BW mag as a dog with milky optics, poor build and poor desgin, and yet several respected reviewer sites e.g. Alula consider the scope to be first rate. I wonder if this is reflective of a lack of consistency in the BW mag testing methodology, a lack of ability on the part of the testers, or genuine sample variation. Or could it be that using a single number to rate optics is a non-starter as it depends too much on what weight is given to each aspect e.g. brightness, contrast, centre sharpness, edge sharpness, FOV etc.

Interestingly the well known Alula scope survey noted that several of the top end scopes that they tested were probably lemons. So, it looks as if there is quite a bit of variation.

So, how does Joe Public make sure that (s)he gets a good 'un and not a lemon, and does buying a Leica/Swaro in reduce the probability of a lemon?

Last edited by Leif : Tuesday 6th January 2004 at 21:14.
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Old Tuesday 6th January 2004, 21:46   #2
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You're right about how can we be totally sure if a purchase is a lemon.
In my local rspb shop they usually only carry one item in the range (well expensive ones) probably for insurance reasons,so you don't have a comparison.
But then again, it would seem to me that reviewers such as Mr. Ingram of b.v.d. and the guys at alula are probably putting the equipment through a more critical testing regime than the quality assurance dept's at the factories.I mean, they can't afford to reject too many products at the end of the line,can they? They must therefore have a % parameter regarding quality.
Does that make sense?
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Old Tuesday 6th January 2004, 22:18   #3
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Test them yourself, there are a lot of field days that optics companies run and the BBWF has tents dedicated to it, never rely on someones oppinion of the product if you can test it first.
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Old Tuesday 6th January 2004, 22:51   #4
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Quote:
Originally Posted by Ashley beolens
Test them yourself, there are a lot of field days that optics companies run and the BBWF has tents dedicated to it, never rely on someones oppinion of the product if you can test it first.
I agree that at the end of the day it is ones own opinion that counts.

It sounds like I should also test the unit that I intend to purchase and be prepared to ask the dealer if I can look through several if one is suspect! I'm not entirely sure they would be happy with this? (Incidentally, one very well known dealer who seems very honest informed me that he had seen several examples of a well known top of the range ~£800 binocular that were out of collimation straight from the box. I'll not mention names as I think it would be unfair to single out one manufacturer.)
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Old Tuesday 6th January 2004, 23:15   #5
Edward woodwood
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look thru lots
don't believe what you read

for reviews try better view desired or alula's site

those in the popular mags are worthless
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Old Wednesday 7th January 2004, 05:31   #6
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Could someone tell me what, where or who is "alula's site" please??

Thanks
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Old Wednesday 7th January 2004, 12:38   #7
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Quote:
Originally Posted by Pol
Could someone tell me what, where or who is "alula's site" please??

Thanks
Alula is a Finnish bird magazine. It is published quarterly (there's an all-English edition) and has thorough, independent reviews of optics. It also has a website which has some but not all of its reviews (www.alula.fi)
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Old Wednesday 7th January 2004, 16:55   #8
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Thank you dogfish - it has become clearer..............
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Old Saturday 10th January 2004, 22:45   #9
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Quote:
Originally Posted by Tim Allwood
look thru lots
don't believe what you read

for reviews try better view desired or alula's site

those in the popular mags are worthless
I am afraid BVD can't be relied on anymore. It is now linked with an optics store. The old info seems to have been OK, though. BVD's sponsor, for one thing, does not carry Leica. So is it any wonder that there is still no mention of the new small Leica scope? The same holds true for the newer types of Leica binoculars. One can also select against a brand by not mentioning it. For a while, I felt that was happening to Nikon as far as their scopes were concerned. But when I wrote to one of the testers (in Holland), I got the reply that it was a problem on the Nikon end of the line. And I remember that I had problems myself for a while just to find the info about their eyepieces on the internet. Meanwhile, that has changed.
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Old Saturday 10th January 2004, 23:25   #10
Edward woodwood
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Thanks for that Leif...I'd heard rumours about the site getting sponsored, seems like they're true then. Do you know of any independent review site aside from Alula?
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Old Sunday 11th January 2004, 01:35   #11
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Reviews of scopes have been seriously deficient or biased, IMHO. Stephen Ingraham (BVD) raved about the Pentax 80 ED scope when it came out, ranking it equally with Swarovski 80 HD, as I recall. But his comparison was of apples to oranges. He tested the Pentax with a fixed-power eyepiece and compared it to the Swarovski with a zoom eyepiece. I compared the Pentax and Swarovski 80mm scopes side-by-side with zoom eyepieces more than two years ago, and the Pentax indeed performed well: performances were so close that I could barely distinguish between them, though I had a slight preference for the Swarovski. However, the Pentax's zoom eyepiece is the size of a soup can, making the scope cumbersome and heavy.

On the occasion when I compared those two scopes, I also compared them against Kowa, Nikon, and Leica, over a period of nearly two hours, mounted in pairs on a tripod that had two heads. This was at a retail establishment, and I ended up buying the 60mm Nikon Fieldscope III ED. I am still as impressed with it every time I use it as I am with my Nikon SE 8x32.

In the past year I have taken every opportunity to view through the latest Leica, Nikon, Swarovski, and Zeiss scopes. I have not been able to use the latest Kowa scope, and have never even seen an Opticron scope. But I have been terribly impressed with the optical quality of every scope I have tried. Every one has had superb resolution, contrast, and color fidelity. I think that the final choice for any really critical buyer will be subjective. Some people prefer one style of focusing mechanism over another, or prefer one company's warranty over another's. But I would be thrilled to own any of the scopes I have tried.

I would ignore published reviews and find a retailer who will allow you to compare scopes, as one did for me. When I finally decided on the Nikon I asked if I could put another identical one next to it to compare, and the dealer declined, but I still bought the one I tested.

As for BVD's relationship with a retail outlet, perhaps Mr. Ingraham will still review the Leica Ultravids and new Leica 62mm scope, even if Simpson Optics does not handle them. However his recent review of the Celestron Regal line was the weakest and least critical review he has ever written. Having spent a decade saying that nobody needs a ten-power binocular, and certainly not one with a 50mm objective lens, he concludes that the 10x50 Regal might actually provide acceptable performance, even if it has only a 5 degree angle of view. This is so incompatible with every other review he has ever written that it makes no sense. It would be much more useful for readers to know how the performance of the 8x42 stacks up against the competition. That used to be the type of review that made BVD such a higly respected source of information.
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Old Sunday 11th January 2004, 06:58   #12
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He now has commercial ties with Zeiss doesn't he?
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Old Sunday 11th January 2004, 09:00   #13
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Reading the Alula reviews, there is a genuine and evident sense of authenticity and concern for accuracy within them. But as has been said, the top scopes are all at the cutting edge of optic design whichever one you choose: Leica, Nikon, Kowa, Zeiss... and for a much lower price, you surely won't go wrong with either the Opticron ES80 or HR66.

I would doubt there would be much variation between scopes - in fact I expect the cost of the top scopes is extra not merely for profit but also owing to better quality control.

I don't think it can be doubted that these top end scopes do produce views that are wider, brighter, clearer and sharper across the whole field of view. And I really do wonder if any reviewer could genuinely pick out a scope in a blinded crossover trial. It wouldn't be beyond an interested magazine editor to arrange such a test, I'm sure.
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Old Sunday 11th January 2004, 09:43   #14
Leif
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Quote:
Originally Posted by pduxon
He now has commercial ties with Zeiss doesn't he?
Yes I have heard that he is now an advisor to Zeiss and that he intends not to continue with the web site, although someone else might take it over from him.

There are some very interesting and helpful comments in this thread, especially from Jonathan. The shopkeeper must have breathed a deep sigh of relief when he finally made his choice! Jonathan: out of interest which shop did you go to? I rather like the idea of using a two scope tripod!

It certainly does not appear to me that his site being linked to a shop influences his opinions. After all his recommended bins are just over half the price of the full-sized Leica/Swaro/Swaro/Nikon equivalents. He does have a review of the Leica 8x42 BN which he compares with the Swaro and Nikon equivalents. It seems a well balanced and well written article and he concludes that for many people - but not him - the Leica will be the best instrument. The Porters site is also connected to a shop (that they run?) and the reviews can be summarised as "Pay more get more". Now that is one site I do not trust one inch.

Here are some other scope/binocular review sites:

Excelcis user reviews of binoculars
Excelcis user reviews of scopes - mainly astro
Scope reviews from the Cornell team - 1998
Recent scope reviews from the Cornell team
Scope/bin reviews in Norwegian
The Weatherman's binocular reviews

I don't entirely trust the Norwegian site as some of the conclusions are a bit at odds with my own and others observations.

However, I certainly don't intend to take the above as a anything other that a way to reduce my short list to a manageable selection of products.

Hopefully we will have lots of helpful equipment reviews on this site. Even a short account is useful! Don't let the fact that someone has already reviewed an instrument put you off. Multiple reviews add value since we are not all the same!
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Old Sunday 11th January 2004, 12:26   #15
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Speaking personally, I always treat reviews of optics reviews with a certain amount of scepticism. When I get round to it, though, my review of reviews of optics reviews will, quite naturally, be completely without bias

Hope you're making progress in your quest Leif.
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Old Sunday 11th January 2004, 18:05   #16
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Leif,

The shop where I compared scopes is in Norman, Oklahoma. It is Christopher's, Ltd., whose website is under the name astronomics.com

They have a fairly full choice of optics in stock, and their prices are as good as, and in some cases better than, other web-based retailers.

My point about Stephen Ingraham's latest review is that it is not up to the same critical standards his reviews became deservedly famous for. I used to find that all of his opinions proved true when I compared the same optics.

As for an opinion on a scope, let me say that I don't think any small scope outperforms the Nikon 60mm Fieldscope III ED. Others may match it, but for the money it is a great buy. The field is truly as sharp and clear at the very edges as at the center, which I have not yet seen in any binocular.

I recall reading in some review that a birder had a Nikon scope leak like a sieve in the tropics. I have wondered if he was using the 78mm Fieldscope, which was not designed to be waterproof. On the other hand, I have not subjected my scope to those extremes. Nikon's new 82mm Fieldscope is warranteed to be waterproof, like the smaller 60mm Fieldscope.

As for ruggedness, I cannot say that the Nikon would survive a severe drop the same way a Leica or other scope would. I have not yet dropped my scope or had it topple over, and I simply don't know how well it would fare. I hope I don't have to find out, though plenty of birders have told me it is inevitable.
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Old Sunday 11th January 2004, 21:07   #17
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Quote:
Originally Posted by Leif
Here are some other scope/binocular review sites:

Excelcis user reviews of binoculars
Excelcis user reviews of scopes - mainly astro
Scope reviews from the Cornell team - 1998
Recent scope reviews from the Cornell team
Scope/bin reviews in Norwegian
The Weatherman's binocular reviews

I don't entirely trust the Norwegian site as some of the conclusions are a bit at odds with my own and others observations.
So far, I have felt that the Norwegian site is pretty unbiased. Can you give us an example where you felt they are considerably off?

Here is another site, this one is from the Netherlands, and it is, therefore, in Dutch.

http://www.tvwg.nl/

Look at their Testrapporten. They have some interesting figures and tables that can be understood by applying your English plus some common sense, I hope.

They are the ones that have not had a chance to test the Nikon scopes, as I mentioned somewhere before.
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Old Sunday 11th January 2004, 22:28   #18
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Swissboy: Thanks for the link. I used an online machne translator. The article mentions that Swarovski can supply a rocket booster for the ELs. Nice idea! Mars next stop. Or perhaps the translator is not so good?

However, I did learn that the author considers the Swaro 8x32 EL and Leica 8x32 BN to be very close optically. This is interesting given the price difference. I have not tested the Swaro so cannot comment. He also seems to say that the Swaro 8.5x42 is no sharper than the Leica 8x32 BN which I know to be nonsense. The Swaro resolves quite a bit more detail. He also seems to say that the Swaro and Leica show similar colour correction. To my eyes the Leica 8x32 BN always shows rather a lot of false colour, and side by side with the Swaro, quite a bit more. (I have seen one other report agreeing that the Leica has poor colour correction.) Of course the macine translation I have is not so good so maybe I have mis-read the results?

The oddities in the Norwegian reports are the Zeiss 8x30 BGAT and the Zeiss scopes. They concluded that optically the Zeiss 8x30 is poor (relatively speaking) which is not true. It is roughly equal to the Leica 8x32 BN. (Better in some respects, not as good in others.) In fairness they did state that they did the test some years ago and the bins are likely to have been improved since, but still, could they really have improved so much? Does a model improve that much? Regarding the Zeiss scopes, they rate them poorly, which goes against the opinions of numerous other testers. (I have not tried them.)
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Old Sunday 11th January 2004, 22:58   #19
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Quote:
Originally Posted by pduxon
He now has commercial ties with Zeiss doesn't he?
He acts as a consultant for Zeiss in the USA. This is shown on the Zeiss.com site. Other manufacturers have "birders" acting as consultants.
Not all areas of optics are subjective, many are measureable. (example: one reviewer stated that a certain binocular had a wider field of view than another, and had a higher transmission, both incorrect, and when asked, stated that it was a subjective review. NO ITS NOT ITS MEASUREABLE.
I am sure that the magazine reviewers intend to help, and do not set out to confuse users.

Last edited by mak : Monday 12th January 2004 at 11:20.
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Old Monday 12th January 2004, 07:48   #20
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What bothers me about just about every scope review I've read is that they are very subjective. They seldom (if ever) take steps to measure even the most simple of optical parameters. For instance, does the optic deliver the magnification claimed? What about the FOV or eye relief? As such, it is very easy for even an exremely fair minded reviewer to let in his or her own bias. And what about the mood they were in that day? Or their memory of the view through some particular optic. Or how their particular eyes might actually be more or less sensitive to a certain type of optical flaw?

Since they are fairly directly attached to our brains, our eyes are very adaptive to faults and differences. This makes objective testing without measurement very difficult.

Side by side "shootout" reports are likely to give the more objective results. When these are done with multiple testers of a variety of experience, then they are even better. If 8 of 10 people agree on some point, then there is probably something to it.

I think that test reports are useful primarily for the sorting out of clearly inferior products and for reporting on feature and usability attributes. Beyond that, I suggest (as others have done) viewing for oneself.
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Old Monday 12th January 2004, 17:31   #21
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Jay: Very true!
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Old Monday 12th January 2004, 20:40   #22
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[As for ruggedness, I cannot say that the Nikon would survive a severe drop the same way a Leica or other scope would. I have not yet dropped my scope or had it topple over, and I simply don't know how well it would fare. I hope I don't have to find out, though plenty of birders have told me it is inevitable.[/quote]


I have owned both the Nkon 60 ED2 and the 78 ED both of which survived unscathed when dropped onto a solid wood floor. Once was bad enough, twice means I must be careless!

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Old Monday 12th January 2004, 21:21   #23
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Quote:
Originally Posted by Leif
Swissboy: Thanks for the link. I used an online machne translator. The article mentions that Swarovski can supply a rocket booster for the ELs. Nice idea! Mars next stop. Or perhaps the translator is not so good?

However, I did learn that the author considers the Swaro 8x32 EL and Leica 8x32 BN to be very close optically. This is interesting given the price difference. I have not tested the Swaro so cannot comment. He also seems to say that the Swaro 8.5x42 is no sharper than the Leica 8x32 BN which I know to be nonsense. The Swaro resolves quite a bit more detail. He also seems to say that the Swaro and Leica show similar colour correction. To my eyes the Leica 8x32 BN always shows rather a lot of false colour, and side by side with the Swaro, quite a bit more. (I have seen one other report agreeing that the Leica has poor colour correction.) Of course the macine translation I have is not so good so maybe I have mis-read the results?

The oddities in the Norwegian reports are the Zeiss 8x30 BGAT and the Zeiss scopes. They concluded that optically the Zeiss 8x30 is poor (relatively speaking) which is not true. It is roughly equal to the Leica 8x32 BN. (Better in some respects, not as good in others.) In fairness they did state that they did the test some years ago and the bins are likely to have been improved since, but still, could they really have improved so much? Does a model improve that much? Regarding the Zeiss scopes, they rate them poorly, which goes against the opinions of numerous other testers. (I have not tried them.)
Yes Leif, machine translations do create very funny results at times. We used to play around with that some time ago. But that booster in Dutch is pretty much what you call it in English. And the machine probably tries the most common usage. Overall, enhancer (of whatever) would probably fit, in this case enhancer of magnification.

As for the comparisons, I don't know sufficient Dutch to try to read all the text, so I use the tables primarily. And there, the sharpness etc is given by a point scale only. So both Swarovski 8.5x42 and Leica 8x32 have the maximum number of 5. But it is well known that larger objectives allow for higher resolution, and maybe they simply took that into account?

The price differences between Swarovski and Leica may in part result from a difference in company philosophy. Leica is known to be stingy when it comes to repairs under warranty, whereas Swarovski handles things more on a "no questions asked" basis. But they need their money as well. So it may simply be paid for at an earlier date, i.e. already when you buy their product. Thus, more expensive (at the time of purchase) does not have to mean better.

Concerning color corrections, we enter a thorny field. It is here where a lot of subjectivity comes into the game. I own a Leica 8x32BA and I have always been extremely pleased by the way colors are shown. The same holds for the Leica Apo Televid 77. My brother now has a new Swarovski ED80. We recently looked at the same distant object (a group of lapwings getting ready for the night, with a golden plover among them) in dull evening light. We both had our wide angle eyepiece on (30x for the Swarovski, 32x for the Leica). For one thing, that 2x difference was quite noticeable in the field. But as for the color rendition, the Swarovski picture was much bluer and therefore colder in appearance. (I had noticed this before under better conditions.) It also seemed darker. Personally, I prefer the Leica, but my brother does not mind. I think it is to a considerable degree a question of what you are used to. At least once we discuss things at this high a level. By the way, both scopes gave us the same limitations of what could still be discerned!

As for the Zeiss scopes, I think BVD did not give them as good a ranking as the Swarovski, again allowing for only subtle overall differences. (That was before Ingraham joined Zeiss, so it was presumably still a trustworthy test.)
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Old Tuesday 13th January 2004, 18:44   #24
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Swissboy: BTW when I referred to false colour, I was referring to fringing, rather than a colour cast. For example, view a bird in flight against a bright sky and you will probably see coloured fringes around the bird. The strength and nature of the fringes varies across instruments and can be quite noticeable. It also tends to be more prominant at the field edges, and is more obvious if you do not align your eyes with the optical axes of the binoculars.

You are not first to assume that false colour refers to a colour cast. I have always assumed - perhaps wrongly - that it was another name for chromatic aberration. Hopefully someone will correct me if I am mistaken.

The term 'booster' is indeed the one used by Swarovski, but without the 'rocket' part!

On the issue of scopes, I think the real advantage of the Swaro 80mm scope over the Leica is the light weight. But is that worth the 50% extra cost? I have to say that for me it is not. The Leica scope looks to be a bargain when compared with the competition. (Who would have thought that a Leica instrument could be described as a bargain?)
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Old Tuesday 13th January 2004, 20:52   #25
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"Chromatic aberration" occurs when light passing through a lens, as well as being focused into a single plane, is also slightly split into its basic colours (ROYBGIV) with each colour being brought to focus on a slightly different plane, i.e. the lens acts not only to focus but as a prism, too.

By using an objective lens element within the construction of a somewhat different glass composition (such as fluorite), the colours can be brought back into a single plane of focus and hence produce an image free of any colour fringing.

I thought "false colour" referred to colour-cast, too. This is caused, I think, when not all of the spectrum of light can pass through the lenses - with some colour being "held back". Also, some light will always be lost by internal reflections and so on - but the light lost might not always be from the whole spectrum, thus the potential exists for the light reaching the eye to lack some of the colours of the full spectrum and so show as "warm" or "cold" or "yellowish". The way out of this is to coat the lenses with minerals that prevent reflections and which do not absorb light of one particular wavelength - or at least absorb all of the visible wavelengths equally.

The eye easily adjusts to colour casts - as any photographer finds out to his dismay when photos look oddly coloured, say under fluorescent lighting - but which was not noticeable to the photographer at the time. The older Swarovski binos always gave a yellowish colour cast, for example, but after a few moments use this "disappeared".
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