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Historical Review of Swift 804 Audubon Binoculars

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Old Thursday 2nd March 2006, 18:09   #51
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Quote:
Originally Posted by Renze de Vries
Rich,

As far as I'm informed, Ed had to let this one go because he splashed out on the ED...
But you're right, this Supreme IS the Audubon at 10 power. And as such the precursor to the Kestrel. As far as our information goes the Audubon 10x50 was issued in the USA under that name, while in Europe it was called (and designated) Supreme. Later the Audubon as well as the Supreme designation disappeared and it became the Kestrel. Important to note here is that in the meantime the revision of the Audubon took place (more compact, lighter body, etc.), with the result that the 10x50 Supreme belongs to the large body, heavyweight category, while the 10x50 Kestrel is much lighter and smaller. However, a 'true' Audubon 10x50 can be found in the large as well as the small body type.
Please correct me if I'm wrong, Ed.

Renze
Hi Renze

Thanks for the additional info it did indeed look like the heavier larger bodied Swift model type
Not many 10 x binoculars have an 8 degree field and good image qualities so still an optical bargain i believe at under £90

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Rich
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Old Thursday 2nd March 2006, 19:25   #52
Renze de Vries
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84.00 GBP to be exact (= 147 USD = 122 Euro).

Renze
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Old Thursday 2nd March 2006, 19:44   #53
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Quote:
Originally Posted by richt
Hi Ed

Glad you have had an enhancing experience with the 804 ED's
I wonder if the 820 ED later model shows this colour purity
I know some BF members prefer the build style/quality of the 804 but if the 820 ED is on par optically then for some its smaller lighter body might be the best thing at the price
Can anyone comment on the ED benefit in the later models ?

Just as an aside a near mint Swift Supreme 10 x 50 (420 ft fov) went for less than £90 recently on the famous bid site
I was sorely tempted as this appeared to be a wide field version of the Audubon but at 10 x

Regards
Rich
Hi Rich (and Renze),

Yes, I was also sorely tempted by the Supreme, and sorry to see it go. However, binoculars are flowing in and out of my house at a prodigious rate. It would have been great to have it, in preparation for the Kestrel history Renze and I are considering.

Not owning an 820 ED I can only speculate that it might be superior to the standard model by an equal margin. It would certainly be worthwhile to look into, since they are still available. However, I'm stopping with the 804s, primarily for financial reasons. I have briefly compared the standard 804, Type 4b(1), and 820 — and came away liking the 804 better. This may have been because I was more familiar with the feel of the 804, or because the demo models were not cared for properly. In any case the bridge construction seemed to be the weak point of the 820, which has been commented upon by others. Again, the binocular had not been well cared for.

Now having observed this ED glass effect, I'm also very curious about other products, such as Minox. As is often the case, however, other variables are also mixed in, e.g, aspheric lenses.

Regards,
ED
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Old Sunday 12th March 2006, 19:41   #54
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ED Revelations and Reflections

Quote:
Originally Posted by elkcub
Today was my first opportunity to put them to the test at Shoreline Nature Preserve in Palo Alto. The mid-1990s BVD comparison by Steve Ingraham with the standard 804 really didn't prepare me for this extraordinary experience. The difference was not subtle at all, more like being given a new pair of eyes. No doubt that sounds like a dramatic overstatement, but, trust me, you're not likely to hear me say that again about another optical product. ...
Ed
After using the 804ED (between torrential rains), they continue to hold me in thrall. I can recall only one similar experience. It occurred after I finally put my analog HiFi equipment together and found myself eagerly playing each record as if it were brand new, to reflect on the subtle nuances that were now revealed.

It's happened again. These wonderful binoculars reveal every bird in a new and subtle light, and I find myself eagerly marveling at commonplace species that have long escaped my attention. Since I recently changed to Kenn Kaufman's field guide, it will be used to reflect the new ED's life list.

ED

Last edited by elkcub : Sunday 12th March 2006 at 22:08.
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Old Tuesday 14th March 2006, 02:42   #55
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Quote:
Originally Posted by elkcub
After using the 804ED (between torrential rains), they continue to hold me in thrall. I can recall only one similar experience. It occurred after I finally put my analog HiFi equipment together and found myself eagerly playing each record as if it were brand new, to reflect on the subtle nuances that were now revealed.

It's happened again. These wonderful binoculars reveal every bird in a new and subtle light, and I find myself eagerly marveling at commonplace species that have long escaped my attention. Since I recently changed to Kenn Kaufman's field guide, it will be used to reflect the new ED's life list.

ED
Hmm, comparing the ED experience to the analog audio experience. What sort of audio equipment were you using? It's an interesting comparison to make. There is a lot of argument about whether analog is an improvement over digital -- or what the nature of the "improvement" is.

As far as the ED Audubons go, didn't you mention that there are other optical improvements in this binoc as well? I certainly believe you about the dramatic difference between the 804s and the EDs -- but could it be something else -- or the sum of all the improvements?
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Old Tuesday 14th March 2006, 05:52   #56
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Quote:
Originally Posted by trashbird
Hmm, comparing the ED experience to the analog audio experience. What sort of audio equipment were you using? It's an interesting comparison to make. There is a lot of argument about whether analog is an improvement over digital -- or what the nature of the "improvement" is.

As far as the ED Audubons go, didn't you mention that there are other optical improvements in this binoc as well? I certainly believe you about the dramatic difference between the 804s and the EDs -- but could it be something else -- or the sum of all the improvements?
Well, I was really referring to the totality of the experience, which in each case has made me enthusiastic to start afresh. Auditory and visual experiences can explode with "color," and devices that bring this out can result in a kind of revelatory experience (epiphany?).

Several factors might account for the improvement including the ED glass itself, air spacing of the objective lenses, or modifications to the oculars, which, incidentally, resulted in a slightly improved shorter eye relief (1mm). It could be a combination of the above, or that minor optical tweaking was done with the air spaced lenses, or greater care was taken in component matching during assembly. What reinforces my belief that that this is characteristic of the 804ED, however, is Steve Ingraham's earlier BVD comment:
Quote:
...The ED glass in the objective does, as you might expect, improve color depth and definition. Colors are slightly more intense, and you can see more different shades and gradiations of the same color. The yellow of a Meadowlark's breast or the blue of a Mountain bluebird's, one solid color through standard binoculars, shows an amazing range of subtly different hues through the ED glass. The improvement, when compared directly to the standard Audubon is very subtle, but definitely there. The effect is probably heightened by the slightly improved contrast that the full multicoating provides. (c. 1993)
Note that he distinguishes between the intensity of colors vs. their shades and gradations, and clearly associates the latter with the presence of ED glass. This brings me to the simile you picked up on: analog vs digital sound. The use of ED glass seems to represent a continuous analog mechanism for control of the color spectrum, whereas, multi-coating, by analogy, is a discrete filter. It's akin to the audio difference between my superb Grace F-9E cartridge with ruby stylus, also no longer on the market, and the much less delicate hi-end Monarchy D/A converter.

Ed
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Old Tuesday 14th March 2006, 09:10   #57
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Quote:
Originally Posted by elkcub
Well, I was really referring to the totality of the experience, which in each case has made me enthusiastic to start afresh. Auditory and visual experiences can explode with "color," and devices that bring this out can result in a kind of revelatory experience (epiphany?).

Several factors might account for the improvement including the ED glass itself, air spacing of the objective lenses, or modifications to the oculars, which, incidentally, resulted in a slightly improved shorter eye relief (1mm). It could be a combination of the above, or that minor optical tweaking was done with the air spaced lenses, or greater care was taken in component matching during assembly. What reinforces my belief that that this is characteristic of the 804ED, however, is Steve Ingraham's earlier BVD comment:

Note that he distinguishes between the intensity of colors vs. their shades and gradations, and clearly associates the latter with the presence of ED glass. This brings me to the simile you picked up on: analog vs digital sound. The use of ED glass seems to represent a continuous analog mechanism for control of the color spectrum, whereas, multi-coating, by analogy, is a discrete filter. It's akin to the audio difference between my superb Grace F-9E cartridge with ruby stylus, also no longer on the market, and the much less delicate hi-end Monarchy D/A converter.

Ed
Ed,

You could simplify by saying the 804ED is similar to the amazing Nikon SE, a binocular that delivers more color and detail than one can imagine.

John
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Old Tuesday 14th March 2006, 18:11   #58
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Quote:
Originally Posted by John Traynor
Ed,

You could simplify by saying the 804ED is similar to the amazing Nikon SE, a binocular that delivers more color and detail than one can imagine.

John
If you enjoy the Nikon SE as much as I do the Swift 804ED, you're also happier than words can express.

Ed
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Old Tuesday 14th March 2006, 18:27   #59
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Historical Note #1: SP Series

For those with historical interests, it has come to light that "SP" and "SPWA" binoculars mentioned on several earlier posts were of British/European origin. SP stands for Swift-Pyser. Of course, WA still means wide-angle. More digging is being done in this area, but it appears that several SP configurations were marketed that did not have US counterparts, such as a 9x42 (not called an Audubon). Renze has a mint one in his possession.

Ed

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Old Tuesday 14th March 2006, 23:44   #60
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Thanks for the invitation Ed. Right, it came in from Italy a week ago. So I'll report.
Well, the 9x42 was mentioned by Otto McDiesel in an earlier thread (http://www.birdforum.net/showthread.php?t=47263) as one of the more illusive Swifts. Information was scarce then (and now) but one thing was clear: the 9x42 wasn't an Audubon but one of a series of three (as we do know now: four) models just below the top range, with prices at about 75% of the Audubons. The series must have ran for a short time and indeed, were probably issued in Europe only.
But what is it like, this rare 9x42? Well, it's of amazing quality. It uses exactly the same housing as the Swift Audubon, only the SPWA is just a tad lighter, possibly from using one ocular lens less (?). Comparing the two I am completely unable to see any difference in optical quality! Sweet spot: same. Coating and colour bias: same. Brightness: same. FOV: according to specs there is a difference, but it's so marginal I can't see it. Because of the slightly higher magnification, resolution is better, and the shorter eye relief - just a few millimeters, eyecups exactly the same as on the Audubon - helps to completely avoid blackouts.
What's intriguing is, what Swift (or Pyser-Swift) could have motivated to put this instrument to the market. The configuration is unusual, but wasn't the 8.5x44 unusual enough? And why give it an optical quality indistinguishable from their flagship? Questions, questions, so we're still digging.

cheers,

Renze

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Old Friday 17th March 2006, 03:28   #61
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Factoid #1: Tethered Objective Covers

I just received two pairs of rubber tethered objective covers from B&H for the Audubon, at 6.95 each. They are very good quality rubber, and work with my 804R and 804ED very nicely, although I assume they were designed to fit the 820 and 820ED. They are too large for the 828 HHS. The manufacturer is Eagle Optics.

Ed

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Old Wednesday 5th April 2006, 03:21   #62
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Greetings!

This is a most fascinating discussion, especially considering that I own an much loved, much valued pair of Audubons, which I wouldn't trade for ANYTHING - by the excellent reference article above, mine would be 804R type 4b(2) - fully multi coated designation. I purchased these in the late 1999, and my serial number is 97****, so they can clearly support the proposed 'year theory'.

I also note that, from the article, my particular Audubons share EVERYTHING with the ED except the actual ED glass itself - including the air spaced objectives and coatings, which the 4b(1)'s do not. This would make mine a perfect candidate for testing the article's assertion that the air spaced objectives may be as important optically as the ED glass itself. It would be interesting to compare a 4b(1), a 4b(2), and an ED side by side - one would think my glass would slot in between them, and perhaps even match the EDs performance-wise, if the assertion is correct. BTW my 804s are in perfect condition, due to the "harsh weather conditions" of Northern California, so if anyone is local and interested, I'll be there...!

All I know is that to my eye, my Audubons have not yet been bested by any comparison I've ever done (even by competitors requiring monthly payments!), and I feel very fortunate to be an original owner of this wonderful birding instrument.

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Old Thursday 6th April 2006, 23:29   #63
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Quote:
Originally Posted by dozercsx
Greetings!

This is a most fascinating discussion, especially considering that I own an much loved, much valued pair of Audubons, which I wouldn't trade for ANYTHING - by the excellent reference article above, mine would be 804R type 4b(2) - fully multi coated designation. I purchased these in the late 1999, and my serial number is 97****, so they can clearly support the proposed 'year theory'.

I also note that, from the article, my particular Audubons share EVERYTHING with the ED except the actual ED glass itself - including the air spaced objectives and coatings, which the 4b(1)'s do not. This would make mine a perfect candidate for testing the article's assertion that the air spaced objectives may be as important optically as the ED glass itself. It would be interesting to compare a 4b(1), a 4b(2), and an ED side by side - one would think my glass would slot in between them, and perhaps even match the EDs performance-wise, if the assertion is correct. BTW my 804s are in perfect condition, due to the "harsh weather conditions" of Northern California, so if anyone is local and interested, I'll be there...!

All I know is that to my eye, my Audubons have not yet been bested by any comparison I've ever done (even by competitors requiring monthly payments!), and I feel very fortunate to be an original owner of this wonderful birding instrument.
Now here is a coincidence made in Heaven! We both live in Northern California. I'm in Sunnyvale, — and you? Perhaps we can get our optics together for a comparison.

I'm somewhat confused about your Audubon. If yours were made in 1997 they should be Fully Multi-Coated 804 HR/5s. We refer to them as Type 4b(2). However, I'm not aware, to this point, that any non-ED HR/5 was ever made with air-spaced objectives. Rather, it should simply have the latest multi-coating, which sets it apart from the original Type 4b(1) and earlier 804R (Type 4a).

Can you come up with evidence that your non-ED has air-spaced objectives? If so, this alone would be a juicy addition to the story.

Regardless of this issue, I own an 804R and 804ED that can be compared with your late model HR/5. Let's get together and do it one day soon.

ED

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Old Saturday 8th April 2006, 04:01   #64
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Wow Elk, talk about a small world - I live in Sunnyvale! Sounds like a comparison's in short order (if the rain ever stops!) - Charleston slough and the Black Skimmers, here we come...!

My comment about the air-spaced objectives comes directly from the reference article, section 3, page 18, in the description of the 804ED (!) as quoted here:

"Optically, the air-spaced objective elements may be as significant as the use of ED glass, but that is usually overlooked. It was introduced with the standard type 4b(2) and is the forerunner of the current model 820ED."

My glasses are indeed the FMC, green coating, 804R HR/5 type 4b(2) - whew! - so as per above ,they should have air-space objectives. (I don't know what to look for to indicate such, as the objectives are sealed, so I'm merely taking the article at face value). I suppose the authors could verify how they determined that particular statement - all I know is that my 804's are razor sharp and very, very good!

DozerCSX
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Old Saturday 8th April 2006, 06:33   #65
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Quote:
Originally Posted by dozercsx
Wow Elk, talk about a small world - I live in Sunnyvale! Sounds like a comparison's in short order (if the rain ever stops!) - Charleston slough and the Black Skimmers, here we come...!

My comment about the air-spaced objectives comes directly from the reference article, section 3, page 18, in the description of the 804ED (!) as quoted here:

"Optically, the air-spaced objective elements may be as significant as the use of ED glass, but that is usually overlooked. It was introduced with the standard type 4b(2) and is the forerunner of the current model 820ED."

My glasses are indeed the FMC, green coating, 804R HR/5 type 4b(2) - whew! - so as per above ,they should have air-space objectives. (I don't know what to look for to indicate such, as the objectives are sealed, so I'm merely taking the article at face value). I suppose the authors could verify how they determined that particular statement - all I know is that my 804's are razor sharp and very, very good!

DozerCSX
Yikes, what a coincidence! Yes, I was at Charleston slough just two days ago. The two dozen or so Black Skimmers were wonderful, as usual, and it would be a good location to make some comparisons now that they built the observation deck to work on. Being retired I can meet with you any day. What's your situation?

Maybe we should talk details by private email.

ED
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Old Saturday 8th April 2006, 14:31   #66
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You can determine from the outside whether your objectives are air spaced by examining the reflection pattern that returns from the objective surfaces.

It requires some careful examination and it's good to know what you're looking for. I've found it's easiest to place a single small light source like a bare light bulb behind me. Hold the binocular in front of you with the objective end pointing toward you. Use one eye only to examine the pattern of reflections of the light bulb in the objective. A cemented doublet will return 3 reflections of the bulb, 2 from the coated front and back surfaces of the doublet and 1 very dim (sometimes almost invisible) and usually tiny reflection from the cementing between the elements. An air spaced doublet will return 4 reflections, all of them showing the color tint of the coating. Be careful not to confuse objective reflections with prism reflections which you will be able to see from certain angles.
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Old Saturday 8th April 2006, 17:47   #67
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Quote:
Originally Posted by henry link
You can determine from the outside whether your objectives are air spaced by examining the reflection pattern that returns from the objective surfaces.

It requires some careful examination and it's good to know what you're looking for. I've found it's easiest to place a single small light source like a bare light bulb behind me. Hold the binocular in front of you with the objective end pointing toward you. Use one eye only to examine the pattern of reflections of the light bulb in the objective. A cemented doublet will return 3 reflections of the bulb, 2 from the coated front and back surfaces of the doublet and 1 very dim (sometimes almost invisible) and usually tiny reflection from the cementing between the elements. An air spaced doublet will return 4 reflections, all of them showing the color tint of the coating. Be careful not to confuse objective reflections with prism reflections which you will be able to see from certain angles.
Henry,

I'll have to work at this a bit harder with an improved lighting set up. However, right now I can see considerable difference between the standard vs. ED objectives. The former shows three distinct reflections, and the latter four — but, they are clustered quite differently and of a different size (smaller). The colors of the reflections are also related to the surface coatings as you said. My Kestrel shows three reflections, like the Standard 804, but the colors are different due to full multi-coating.

Many thanks for the tip. I'll probably comment further after a little more work to perfect the technique. This may come in very handy because there is some (yet unsubstantiated) indication that the latter 804EDs had cemented doublets and were not air-spaced.

Thanks,
ED
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Old Saturday 8th April 2006, 22:45   #68
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Elk,

I realized after my last comment that

(1) YOU were the author, so I was already speaking to The Source (!), and
(2) In re-re-reading, I see how I could have misread the quote - "with" could refer to the 804ED itself, instead of an air-spaced objective reference to the 804R 4b(2).

In addition, I checked the objectives this morning as per Henry's insightful instructions, and I definitely did not see 4 reflections, so I think you're right - mine does not appear to be an air-spaced objective. Of course, we can doublecheck when we meet for the full comparison.

Man, ya learn somethin' every day around here! Thanks...

Last edited by dozercsx : Saturday 8th April 2006 at 22:49. Reason: punctuation
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Old Sunday 9th April 2006, 08:10   #69
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Henri,

What's not discussed here yet is the presumed OPTICAL advantage of air spaced objective lenses versus cemented doublets. I for one don't see any advantages. Do you?

Renze
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Old Sunday 9th April 2006, 19:21   #70
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Quote:
Originally Posted by Renze de Vries
Henri,

What's not discussed here yet is the presumed OPTICAL advantage of air spaced objective lenses versus cemented doublets. I for one don't see any advantages. Do you?

Renze
The air-spaced doublet objective has two more lens-to-air surfaces than a cemented doublet, making for more reflections. Before multicoating, that was more opportunity for light loss through the objective. Also, cemented doublets are cheaper to make and to mount in binoculars. The cemented lens surfaces don't have to be as well figured as in air-spaced doublets, and more care has to be used to get the individual elements of the air-spaced elements properly mounted and aligned. The benefit of the air-spaced doublets is that they offer more freedom for the optical designer to overcome certain abberations.

Here's an interesting source:

http://www.atmsite.org/contrib/Cerag...pter%203b.html

The introductory paragraphs for each section on cemeted and air-spaced doublets are pretty readable. After that, my eyes start crossing. But here is the science of it.

Last edited by trashbird : Sunday 9th April 2006 at 19:40.
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Old Sunday 9th April 2006, 23:08   #71
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Quote:
Originally Posted by trashbird
The air-spaced doublet objective has two more lens-to-air surfaces than a cemented doublet, making for more reflections. Before multicoating, that was more opportunity for light loss through the objective. Also, cemented doublets are cheaper to make and to mount in binoculars. The cemented lens surfaces don't have to be as well figured as in air-spaced doublets, and more care has to be used to get the individual elements of the air-spaced elements properly mounted and aligned. The benefit of the air-spaced doublets is that they offer more freedom for the optical designer to overcome certain abberations.

Here's an interesting source:

http://www.atmsite.org/contrib/Cerag...pter%203b.html

The introductory paragraphs for each section on cemeted and air-spaced doublets are pretty readable. After that, my eyes start crossing. But here is the science of it.
Wow, what a fantastic article! When the reader is done, a link to Chapter 4 can be found at the end to tell all about Apochromats and ED glass. Thank you, thank you.

ED
PS. Did I say thank you?
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Old Sunday 9th April 2006, 23:18   #72
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Trashbird,

Thank you. So by using air-spaced doublets it's possible to make optically better binoculars. But that's theory. How about practice? I mean, can we see the difference? And if so, where (in what binoculars on the market today)?

Renze
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Old Sunday 9th April 2006, 23:27   #73
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Quote:
Originally Posted by elkcub
Wow, what a fantastic article! When the reader is done, a link to Chapter 4 can be found at the end to tell all about Apochromats and ED glass. Thank you, thank you.

ED
PS. Did I say thank you?
You're welcome, ED. Thanks really should go to Mr. Ceragioli, who created this fine website.
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Old Monday 10th April 2006, 00:30   #74
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You're welcome, ED. Thanks really should go to Mr. Ceragioli, who created this fine website.
trashbird,

Ah, yes, but you get the credit for finding it for us — I've been looking for a comprehensive treatise to no avail.

Renze,

I started this Zeiss thread: http://www.birdforum.net/showthread.php?t=55420 with a similar question in mind. But after 103 viewers there have been no comments. I probably framed the question wrong.

I suspect much of the issue is design implementation. Namely, although I see a stunning improvement in clarity and color gradation using the 804ED (as did Steve Ingraham in '93), other binos using ED or Flourite elements may or may not produce similar results. I wish I had a Zeiss dealer in the vicinity, since they seem to be the most likely candidates for low power binoculars.

ED

Last edited by elkcub : Monday 10th April 2006 at 07:27.
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Old Monday 10th April 2006, 13:57   #75
henry link
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I'll add my thanks to trashbird for the link to Mr. Ceragioli's work. Chapter 4 is by far the best information I've seen on APO objectives. Notice that all the objective designs under discussion have much higher focal ratios than binocular objectives. The lowest focal ratio even discussed was the f/6 Zeiss APQ and that's an oil spaced Fluorite triplet. Binoculars belong in a completely different class of optics. The f/3.5-f/4.5 objectives in small binoculars, even if they are triplets and/or use ED glass have much higher levels of aberrations. I've never seen any binocular with optics good enough to reasonably be called a high quality telescope. The optics are just too fast. The subjective image quality only looks good, even in the best binoculars, because the magnification is kept extremely low by telescope standards. Even then the problems are visible, just not obtrusive.
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