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Old Monday 20th January 2020, 21:53   #276
jan van daalen
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Quote:
Originally Posted by Rico70 View Post
It seems to me quite understandable
You did a great job, but you don't explain how you do the tests.

And the German part has to be translated separately.
This point is interesting here, but I think it refers to the complete binoculars and not to the direct measurement of the prismatic system (tell me if I'm wrong):
[...]laboratory tests show that the influence due to aberrations and manufacturing tolerances is significantly higher than that due to the quality differences in the phase coatings[...]

Another interesting point is that they imagine a test on the limit resolution ...

Too bad that only Swarovski replied and without giving accurate explanations. Maybe there is reserve on these crucial points?

Looking at the photos of the tests (are they photos?) I think the best is the Ultravid, with which you can see at the same time, the Moon, Saturn and Jupiter
http://www.verrekijkerforum.com/download/file.php?id=65

Rico,

If you would read it, you will read how it was done.
BTW, Swarovski did gave accurate explanations.
Read it again.

Jan

Last edited by Troubador : Tuesday 21st January 2020 at 07:19. Reason: typo
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Old Tuesday 21st January 2020, 02:29   #277
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Originally Posted by Thomas_M View Post
Henry,

thanks a lot, but as far as I can see the shape of both prisms in the Retrovid is quite different from that in your drawing. Frankly, to me the prisms do not look like Schmidt Pechan. If you take into accont all images Jan has posted it seem to me that the light enters from the objetive lens to the left prism and exists from the roof prism. I would be interesting to have a look with the apperture in front of the eyepiede could be removed.


Thomas
Thomas,

Thanks for sending me back to the drawing board. Once again I had to delete a post with incorrect information. My latest mistake resulted from second guessing something I thought I knew, which is that the roof can be in either the Schmidt or the Bauernfiend prism in what we call a Schmidt-Pechan prism. When the roof is in the Schmidt prism the Bauernfeind prism requires mirror coating and when the roof is in the Bauernfeind prism the Schmidt requires mirror coating.

Almost all illustrations I found of S-P prisms show the roof in the Schmidt, but I finally found one with the roof in the Bauernfeind from a diagram of an old Swarovski 7x42 SLC. As you can see below it's a much better match for what we can see of the Retrovid prism in Jan's photo. It's in good agreement with your interpretation of the light from the objective entering the left prism (Schmidt, mirror coated with no roof) and exiting the right prism (Bauernfreind, roof with no mirror coating).

Jan's cutaway of the Swarovski EL SV below shows that the prism arrangement from the old SLC has been abandoned in favor of a Bauernfeind entrance prism (mirror coated with no roof) and a Schmidt exit prism (roof, no mirror coating).

Henry
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Old Tuesday 21st January 2020, 14:19   #278
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Thought I would add these screen captures of quotes from "Opto-mechanical Systems Design" by Paul R Yoder jr.

The reference to "Seil, 1991" is to Konrad Seil's 1991 paper "Progress in Binocular Design", in which he describes the coating compromise inherent in the Schmidt-Pechan variants.
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Old Tuesday 21st January 2020, 16:26   #279
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Originally Posted by henry link View Post
Thomas,



Almost all illustrations I found of S-P prisms show the roof in the Schmidt, but I finally found one with the roof in the Bauernfeind from a diagram of an old Swarovski 7x42 SLC. As you can see below it's a much better match for what we can see of the Retrovid prism in Jan's photo. It's in good agreement with your interpretation of the light from the objective entering the left prism (Schmidt, mirror coated with no roof) and exiting the right prism (Bauernfreind, roof with no mirror coating).

Jan's cutaway of the Swarovski EL SV below shows that the prism arrangement from the old SLC has been abandoned in favor of a Bauernfeind entrance prism (mirror coated with no roof) and a Schmidt exit prism (roof, no mirror coating).

Henry
Henry,

thanks a lot, this looks very convincing!

I am learning, so far I thought, that a Schmidt Pechan prism is always characterized by a Schmidt prism with roof and a Bauernfeind prism without roof, but it seems that there are different variants which are all called Schmidt Pechan.

Then, I have a hard time to understand your comparison with the Swarowski glasses, it ist also not clear to me what is shown on the pictures with the cuts (Zeiss Victory SF right, Swaro EL SV left?)

I am confused, you are saying that the design of the retrovid resembles that of the old 7x42 SLC? To me it looks similar to that of the Zeiss Victory SF, although the Schmidt prism of the retovid is much wider.

Thomas
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Old Tuesday 21st January 2020, 16:45   #280
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Quote:
Originally Posted by Thomas_M View Post
Henry,

thanks a lot, this looks very convincing!

I am learning, so far I thought, that a Schmidt Pechan prism is always characterized by a Schmidt prism with roof and a Bauernfeind prism without roof, but it seems that there are different variants which are all called Schmidt Pechan.

Then, I have a hard time to understand your comparison with the Swarowski glasses, it ist also not clear to me what is shown on the pictures with the cuts (Zeiss Victory SF right, Swaro EL SV left?)

I am confused, you are saying that the design of the retrovid resembles that of the old 7x42 SLC? To me it looks similar to that of the Zeiss Victory SF, although the Schmidt prism of the retovid is much wider.

Thomas
Hi Thomas,

Yes, the right one is the SF.
It is easy to see.
One objective lens less and the prism "upsidedown" causes a weight shift towards the eyepiece, resulting in a complete neutral balance. Something the original EL also had but the ELSV lacks.

Jan
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Old Wednesday 22nd January 2020, 07:43   #281
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Quote:
Originally Posted by jan van daalen View Post
If you would read it, you will read how it was done.
BTW, Swarovski did gave accurate explanations.
Read it again.
Jan, as you may have guessed from my answers, I had already read everything.

Referring to how you do the tests, I was asking broadly which instrumentation you use, in addition to the polarizing filter. Do you only use the eye and light you have in the office (neon, led, etc.)? Do you use your phone's camera or some special capture equipment with maybe the telecentric lens? If you use a commercial camera, which one? Do you use a normal, wide-angle lens, or which one? Have you profiled the sensor and the lens for the light you use or do the test without control?

I'm not here to tell you are "quack" (don't worry ), I just wanted to understand the general method and level of your phase tests.
Even Swarovski was not complete in the description (at least in the part you reported), and for me it says nothing about the tests. He only mentions some typologies (e.g. MTF) and some regulations that nobody knows about, if he doesn't have the opportunity to read them in full.

Simply this ... my friend!


PS:
forgive me if I'm asking you too complex questions.
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Old Wednesday 22nd January 2020, 10:02   #282
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Rico70, post 281,
The data you ask form Jan van Daalen can only be obtained from a specialized research laboratory, which has the possibilities to measure thickness and composition of ultrathin layers. From your questions I get the impression that you have no experience whatsoever with thin layer research etc. Is that correct?
Gijs van Ginkel
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Old Wednesday 22nd January 2020, 10:28   #283
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Rico70,
In addition to my previous post: there is a very good paper about phase coatings which is worthwile to read:
Adolf Weyrauch and Dr. Bernd Dörband, "P-coating: optimized image quality for binocuars using phase-corrected roof prisms", Deutsche Optikerzeitung nr4, 1988.
By the way: you make the owner of this forum very rich by your posts: every click is an addition to his bank account.
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Old Wednesday 22nd January 2020, 10:46   #284
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Quote:
Originally Posted by henry link View Post
Thomas,

Thanks for sending me back to the drawing board. Once again I had to delete a post with incorrect information. My latest mistake resulted from second guessing something I thought I knew, which is that the roof can be in either the Schmidt or the Bauernfiend prism in what we call a Schmidt-Pechan prism. When the roof is in the Schmidt prism the Bauernfeind prism requires mirror coating and when the roof is in the Bauernfeind prism the Schmidt requires mirror coating.

Almost all illustrations I found of S-P prisms show the roof in the Schmidt, but I finally found one with the roof in the Bauernfeind from a diagram of an old Swarovski 7x42 SLC. As you can see below it's a much better match for what we can see of the Retrovid prism in Jan's photo. It's in good agreement with your interpretation of the light from the objective entering the left prism (Schmidt, mirror coated with no roof) and exiting the right prism (Bauernfreind, roof with no mirror coating).

Jan's cutaway of the Swarovski EL SV below shows that the prism arrangement from the old SLC has been abandoned in favor of a Bauernfeind entrance prism (mirror coated with no roof) and a Schmidt exit prism (roof, no mirror coating).

Henry
OK, find the difference SLC/SF/ELSV

Jan
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Old Wednesday 22nd January 2020, 10:55   #285
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Quote:
Originally Posted by Rico70 View Post
Jan, as you may have guessed from my answers, I had already read everything.

Referring to how you do the tests, I was asking broadly which instrumentation you use, in addition to the polarizing filter. Do you only use the eye and light you have in the office (neon, led, etc.)? Do you use your phone's camera or some special capture equipment with maybe the telecentric lens? If you use a commercial camera, which one? Do you use a normal, wide-angle lens, or which one? Have you profiled the sensor and the lens for the light you use or do the test without control?

I'm not here to tell you are "quack" (don't worry ), I just wanted to understand the general method and level of your phase tests.
Even Swarovski was not complete in the description (at least in the part you reported), and for me it says nothing about the tests. He only mentions some typologies (e.g. MTF) and some regulations that nobody knows about, if he doesn't have the opportunity to read them in full.

Simply this ... my friend!


PS:
forgive me if I'm asking you too complex questions.
Hello Rico,

One can never ask to much questions
Can it be answered, that is the question.
Photo's are taken with a Canon 5D Mark IV, macro 100mm F2.8.
On the attached pic you see our test facility which is very, very secret

Jan
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Old Wednesday 22nd January 2020, 11:34   #286
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Quote:
Originally Posted by Gijs van Ginkel View Post
From your questions I get the impression that you have no experience whatsoever with thin layer research etc. Is that correct?
Is having experience with soap bubbles inherent?

Quote:
Originally Posted by Gijs van Ginkel View Post
The data you ask form Jan van Daalen can only be obtained from a specialized research laboratory, which has the possibilities to measure thickness and composition of ultrathin layers.
Honestly, I too I don't have a specialized "soap bubble" (ultrathin layers) lab either.
But you instead, yes?

Quote:
Originally Posted by Gijs van Ginkel View Post
there is a very good paper about phase coatings which is worthwile to read:
Adolf Weyrauch and Dr. Bernd Dörband, "P-coating: optimized image quality for binocuars using phase-corrected roof prisms", Deutsche Optikerzeitung nr4, 1988.
Thanks for the advice.

Quote:
Originally Posted by Gijs van Ginkel View Post
you make the owner of this forum very rich by your posts: every click is an addition to his bank account.
You're right, and I should get paid for this
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Old Wednesday 22nd January 2020, 11:43   #287
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Photo's are taken with a Canon 5D Mark IV, macro 100mm F2.8.
On the attached pic you see our test facility which is very, very secret
Thanks, Jan. Let's go back to the Trinovids ...
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Old Wednesday 22nd January 2020, 11:56   #288
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Rico, post 286,
-1- Soap bubbles: yes I do have experinece with them, but mostly in our bathtub, do you have the same experimetal set-up?
-2- I personally don't have such equipment but the research institute I am connected with does, interesting kind of sport and needs special skills and knowledge to operate it.
-3-It s a pleasure.
-4-We could share the streams of money coming in, just as in Italy scientists are very very poor in the Netherlands.
Gijs van Ginkel
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Old Wednesday 22nd January 2020, 12:26   #289
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Quote:
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I personally don't have such equipment but the research institute I am connected with does, interesting kind of sport and needs special skills and knowledge to operate it.
I understand perfectly. I don't have all those competence, I know I could have them, but I also know that competence often has high costs and few earnings.

Quote:
Originally Posted by Gijs van Ginkel View Post
We could share the streams of money coming in, just as in Italy scientists are very very poor in the Netherlands.
Maybe it's a technique to bring out the best ideas to exploit faster and more completely.


PS:

I usually take the shower, not the bathroom.
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Old Wednesday 22nd January 2020, 16:02   #290
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OK, find the difference SLC/SF/ELSV

Jan
Hey Jan,

Which model SLC is that? It looks like the prism design is the same as the diagram I posted, but the eyepiece and objective designs are different from the full diagram of the 7x42 SLC below.

If the 7x42 diagram is accurate then the eyepiece in that model was a 5 element Erfle and the focusing was done by moving the objective doublet behind a fixed cover glass like the 8/7x30 SLCs. I wonder if only the 50/56mm models used an internal focusing lens behind the objective doublet?

I also notice that in the 7x42 diagram (which must be post 2002 since it includes SWAROBRIGHT mirror coating) all the prism glass to air surfaces are coated with SWAROTOP multi-coating. Is that just a mistake or had something changed since Seil's article in 1991?

BTW, how many of those sawn in half binoculars do you have around?

Henry
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Old Wednesday 22nd January 2020, 16:12   #291
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"You're right, and I should get paid for this"

There are a few things in life I am absolutely sure of,... a few, and the probability of this not happening is one of them.

Andy W.
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Old Wednesday 22nd January 2020, 16:40   #292
jan van daalen
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Hey Jan,

Which model SLC is that? It looks like the prism design is the same as the diagram I posted, but the eyepiece and objective designs are different from the full diagram of the 7x42 SLC below.

If the 7x42 diagram is accurate then the eyepiece in that model was a 5 element Erfle and the focusing was done by moving the objective doublet behind a fixed cover glass like the 8/7x30 SLCs. I wonder if only the 50/56mm models used an internal focusing lens behind the objective doublet?

I also notice that in the 7x42 diagram (which must be post 2002 since it includes SWAROBRIGHT mirror coating) all the prism glass to air surfaces are coated with SWAROTOP multi-coating. Is that just a mistake or had something changed since Seil's article in 1991?

BTW, how many of those sawn in half binoculars do you have around?

Henry
Hi Henry,

To start with the last question,
Top shelf first pic is:
Swarovski EL 10x42, Swift riflescope?, Swarovski SLC 7x50, Leica Televid 77, Swarovski SLC 7x50, Swarovski SV 8.5x42.
Bottom shelf:
Swarovski EL 10x42, Zeiss HT 10x42, Zeiss SF 10x42.

Second pic top shelf:
Leica Trinovid 12x50, Leica Geovid 8x42, Leica Trinovid 10x42, Leica Ultravid 10x42, Swarovski SV 10x42, Swarovski companion 8X30.
Bottom shelf:
Opticron Oasis 10x42 (thanks Chris) Swarovski ATM80 25-50,


Jan
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Old Wednesday 22nd January 2020, 18:39   #293
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Hey Jan,

Which model SLC is that? It looks like the prism design is the same as the diagram I posted, but the eyepiece and objective designs are different from the full diagram of the 7x42 SLC below.

If the 7x42 diagram is accurate then the eyepiece in that model was a 5 element Erfle and the focusing was done by moving the objective doublet behind a fixed cover glass like the 8/7x30 SLCs. I wonder if only the 50/56mm models used an internal focusing lens behind the objective doublet?

I also notice that in the 7x42 diagram (which must be post 2002 since it includes SWAROBRIGHT mirror coating) all the prism glass to air surfaces are coated with SWAROTOP multi-coating. Is that just a mistake or had something changed since Seil's article in 1991?

BTW, how many of those sawn in half binoculars do you have around?

Henry
Hi Henry,

The cut a way is the SLC 7x50.
Next month I'll be at Swaro's and will ask if a 7x42SLC durchschnitt is still available in their collection.

The 50/56 have a focus lens behind the doublet objective lens and it's reach is 8mm.

I can't give you a accurate answer regarding Seil's article.

Jan
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Old Wednesday 22nd January 2020, 20:22   #294
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Thanks Jan,

An amazing collection you have there.

Maybe we could start a new thread devoted to just cutaways. I've collected some I could add and John Roberts must have dozens.

Henry
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Old Wednesday 22nd January 2020, 20:27   #295
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Jan, Henry,

thanks a lot for all the interesting information!

Thomas
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Old Wednesday 22nd January 2020, 20:34   #296
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Thanks Jan,

An amazing collection you have there.

Maybe we could start a new thread devoted to just cutaways. I've collected some I could add and John Roberts must have dozens.

Henry
Good idea and we could swap the doubles
I bought the Trinovid 12x50 at the Leica store in Wetzlar during the Noctivid launch for 300,00 euro and saw a similar one going on Catawiki for 1.000,00 euro. Auch....

Open the thread and I'll follow you.

Jan

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Old Wednesday 22nd January 2020, 23:55   #297
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Firstly, Jan what a fabulous collection you’ve amassed! (post #292)

Secondly, as Henry indicates (post #290) both the original series x50 and x56 SLC’s have the more usual objective construction of a fixed doublet and a moving focusing lens,
see the following from two seperate eBay listings by canadiansportsoptics:

- a 7x50 SLC (one image clearly shows the marking on the focuser; and it’s marked on the hinge where there is usually just the serial number: ‘D6739 94079 • TEST’, so work done by Swarovski)

- a x56 SLC (the magnification is not specified; the display mount indicates the work was done by Swarovski)


Additionally:
A) All the x50’s (7x50, 8x50 and 10x50) have 7 lenses per side, with similar pattern objectives and eyepieces (per various images that I’ve seen)

B) Both the 8x56 and 15x56 are listed as having a 3 piece objective, but the 15x56 is listed as 50gm (around 2 oz) heavier with 2% less transmission (at 88%)


I too have been thinking for a while of a seperate thread for each major brand with a compilation of cross-section and cutaway images
(currently images are scattered across a variety of threads)


John


p.s. And an image of the 7x42 and 10x42 construction (there was no 8x42 original series SLC), from Elkcub at: https://www.birdforum.net/showpost.p...&postcount=242
Both the x42's and the Mk II x30's have the same pattern objective of a single glass at the front and then a dual lens focuser
- with the x30's the front element is a planar piece of glass that seals the objective but has no optical function, see the image and details at: https://www.birdforum.net/showpost.p...19&postcount=9
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Old Friday 24th January 2020, 16:49   #298
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The Retrovid is back from our technician and will go to Gijs for a transmission chart.
I traded a Leica 7x35GA Trinovid from 1986 so this makes a 1966, 1967, 1982, 1986 and a 2020 model available for comparison.
Jan
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Old Friday 24th January 2020, 17:10   #299
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Thanks Jan, for all your continued effort to analyze the 'specimen'. I appreciate you would take the time to do all this and share it with the forum. And thanks to everyone else for contributing to an 'illuminating' thread.

-Bill
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Old Friday 24th January 2020, 17:41   #300
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Thanks Jan, for all your continued effort to analyze the 'specimen'. I appreciate you would take the time to do all this and share it with the forum. And thanks to everyone else for contributing to an 'illuminating' thread.

-Bill
You're welcome Bill..........how is the scope treating you?
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