Leica Reichert Jung Polyvar (models)

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JWW
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Re: Leica Reichert Jung Polyvar (models)

#31 Post by JWW » Thu Feb 27, 2020 2:09 am

Being completely new to the Polyvar MET, what are the best objectives? I assume they made other Fluor's and APO's. My MET came with;

Plan Fluor 50x/0.85 Epi
Plan 20x/0.40 Epi IK
Plan 5x/.0.10 Epi
Plan 2x/0.04

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Re: Leica Reichert Jung Polyvar (models)

#32 Post by apochronaut » Thu Feb 27, 2020 9:13 pm

You can find on any given day; Plan, Plan Fl, Plan Fluor and Plan Apo objectives available used. Less frequently you will find the designation Plan Fl Apo, although I cannot say for sure if that designation was used on any M28 oo/0 objectives.
The designations morphed over the years. I would suspect that Plan Fl , would be the same as Plan Fluor. Any Plan Fl I have seen have at least some engraving on the barrel whereas most of the Plan Fluor have paint and the newer matte finish rather than the older polished chrome. You can find such objectives, which in all other ways seem identical.

Plan Fl Apo seems also to be the same , although the only direct comparison I have been able make is with R.M.S. oo/.17 objectives where the designation Plan Fl Apo and Plan Fluor were used for the same objective made for different markets. It's really just a notation of just how good those fluorite objectives are.

The Plan Apos are definitely on the next level.
Reichert did not use the term achromat or achro for any of the Austrian made objectives. Planachro appears on some U.S. ones, though, so if you see just Plan on an objective, it is a Plan Achromat.

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Re: Leica Reichert Jung Polyvar (models)

#33 Post by JWW » Fri Feb 28, 2020 2:34 am

Thanks. Here's what I snagged. Everything seems to be fine. I did clean it up of course. It also came with a Semprex stage.
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Re: Leica Reichert Jung Polyvar (models)

#34 Post by apochronaut » Fri Feb 28, 2020 2:51 pm

Why, that looks perfectly useful to me. Very nice. Is the 2X not an epi as well? Any other 2's I have seen do not have that extended light shield around the objective.

If you are looking to fill the nosepiece, there are fairly regular listings for lots of 10X .20 plan and 10X .20 planfluor L.W.D. objectives. Also 100X .90 planfluor and 100X .70 planfluor L.W.D., although that seems to be pushing the envelope a little. I think there may have been a 63X as well and some 100X oil immersion offerings.

member wporter knows a lot more about the vertically illuminated Reichert stuff than I do.

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Re: Leica Reichert Jung Polyvar (models)

#35 Post by PeteM » Fri Feb 28, 2020 4:41 pm

Looks as if you'll have reflected DIC as well.

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Re: Leica Reichert Jung Polyvar (models)

#36 Post by wporter » Fri Feb 28, 2020 4:46 pm

Member wporter is in the midst of a move and does not have access to documentation, nor his Reichert objectives, so he's not much help. My scope is a Univar, but uses some of the same optics as the Polyvar Met.

But I will say that the Plan Fluors go down at least to 5x, although quite frankly, at the lower powers, I could not tell much if any difference between the plans and the plan fluors. The LWDs are very useful for certain circumstances and specimens, but of course, having lower N.A.s, lose a little resolution as compared to the same mag without LWD.

You should have a great time with your Met. For a preview of epi-DIC, check out my video at https://www.youtube.com/watch?v=O7cPGv0bTDk

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Re: Leica Reichert Jung Polyvar (models)

#37 Post by JWW » Fri Feb 28, 2020 6:50 pm

Hopefully I can get this up and running soon. As I mentioned before, I'm not familiar with this particular scope. I am by no means an expert with scopes but I do have several other scopes, a complete PZO Biolar with DIC, PhA, PhS and PhZ, Optiphot with POL, DIC, Nomarski, Fluorescence and a Nikon MM-11. I did open up the MET for a visual inspection and everything was extremely clean. It has what I assume to be a camera port on once side. Looking through the camera port the image appears to be off way to the left out of the field of view and way off centered. Hopefully something didn't get knocked out of alignment. I'm not sure what may be wrong, if anything. Just wondering if anyone has direct experience hooking up a DSLR to this camera port. I was 'thinking' of removing the top section, fabricate a new cover plate and machine a camera port (tube adapter) there. I should mention that I don't have the original power supply. I'm going to use one of my Optiphot power supplies to fire up the built in illumination. I haven't done that yet and was just using a couple Jansjo LED lamps along side the objective for illumination. :lol:
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Re: Leica Reichert Jung Polyvar (models)

#38 Post by MWK » Fri Feb 28, 2020 7:43 pm

Very nice! How are the optics in the binocular tube? Is the left eye a tint of blue vs the right side being reddish? I have the same microscope and unfortunately I have some delamination in the prism which is causing this color shift. I'm in the process of seeing if I can repair them, but would like to know if all Polyvar are prone to this with age or if it's just specifically my scope. It was left in a garage through the harsh seasons in Canada so...

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Re: Leica Reichert Jung Polyvar (models)

#39 Post by MWK » Fri Feb 28, 2020 7:47 pm

Also, as for the camera port. If the port was in fact used with the 35mm camera adapter, you might need the 0.5x lens that comes with that adapter to reduce the image size to fit the sensor on the DSLR. I was able to fabricate a custom adapter that used this 0.5x lens from the original camera adapter and then attached a Canon Mount adapter to it with amazing results. I'll try to post something later, but the adapter attaches on top of the microscope so it's not the same set up as yours.

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Re: Leica Reichert Jung Polyvar (models)

#40 Post by JWW » Fri Feb 28, 2020 9:24 pm

MWK wrote:
Fri Feb 28, 2020 7:43 pm
Very nice! How are the optics in the binocular tube?
FYI I'm not getting notification of new replies to this thread. I have everything setup to do so. Anyway based on the incorrect illumination I'm currently using the optics are excellent while viewing a wafer thru the binos.

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Re: Leica Reichert Jung Polyvar (models)

#41 Post by JWW » Sat Feb 29, 2020 2:47 am

delete
Last edited by JWW on Sat Feb 29, 2020 7:36 am, edited 1 time in total.

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Re: Leica Reichert Jung Polyvar (models)

#42 Post by microb » Sat Feb 29, 2020 6:43 am

Hi,

What kind of milling do you have? You mentioned doing new parts and adapters.

Thanks,
Ted

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Re: Leica Reichert Jung Polyvar (models)

#43 Post by JWW » Sat Feb 29, 2020 7:47 am

microb wrote:
Sat Feb 29, 2020 6:43 am
Hi,
What kind of milling do you have? You mentioned doing new parts and adapters.
Thanks,
Ted
Bridgeport mill and other machining stuff. I restore vintage telescopes for a hobby so I taught myself how to machine. I also am capable of welding about anything. Once I know HOW and IF I can adapted something to the top of the MET, I might simply 3D print something. Since I'm completely new to this forum I might pass something on to you that you might be interested in. RafCamera specializes in microscope and camera adapters and in my opinion makes quality parts. He will make you one-offs as well if he doesn't have what you want. Nice guy to. He's based in Russia so it take a while to get here but well worth it in my opinion.

https://rafcamera.com/adapters/microscope-adapters

-JW:

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Re: Leica Reichert Jung Polyvar (models)

#44 Post by JWW » Mon Mar 02, 2020 3:37 pm

Has anyone had success mounting a digital camera on the side port of a Polyvar MET like the one I posted pictures of? Either the side port or PREFERABLY fabricating and modifying something that will work on the TOP of the MET microscope as some models have?

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Re: Leica Reichert Jung Polyvar (models)

#45 Post by wabutter » Sun Mar 08, 2020 5:40 am

Update to some of the most recent post..

Mounting a DSLR on the side port is not trivial. If I remember correctly, Diagnostic Instruments made some adapters that make it possible. Don’t know if they are stilll available though. I would need to see the adapter that is currently mounted with out the dust cap to understand better which adapter you have. One of the problems in mounting a DSLR camera with sensor pointed down with that adapter is most DSLRs are too big to clear the microscope stand.
To the comment on part of the field being occluded to the camera port, That port is activated by the dual reflex module, this is the prism assembly that extends to the right side of the scope with the little silver knob on the bottom. You need to check that it is fully engaged. Two versions of this device were offered. One with a 90/10 splitter another that had a 50/50 splitter. The opening to the right usually had a cover when the Macroscope was not attached.
Reichert did not offer a 63x objective for the Polyvar. All Polyvars had a 0.8, 1.0, 1.25, 2.0 mag changer. For Life Science the 40x with the 1.25 mag changer, that gets you to that mag range. The Met version could have a 2.5x in place of the of the lower positions.
The illumination could be driven from a standard power supply, but the camera shutter for top camera port is built into the power supply for the stand. There was a flat plate with a Cmount that was available for the Infrapol version of the Polyvar. The was. O Binotube on the Infrapol so the light went directly to the port.

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Re: Leica Reichert Jung Polyvar (models)

#46 Post by microb » Sun Mar 08, 2020 11:06 pm

JWW wrote:
Mon Mar 02, 2020 3:37 pm
Has anyone had success mounting a digital camera on the side port of a Polyvar MET like the one I posted pictures of? Either the side port or PREFERABLY fabricating and modifying something that will work on the TOP of the MET microscope as some models have?
I'd like to also put a an attachment above like the mentioned replacing the top of the Polyvar, but on a DMR. Where are the famous Leica corrections being done? I have to test this out. Does the lens tube do chromatic correction? Or is it the eye pieces and the vertical path relay lens, like for the a Olympus BH2 with the objectives of the time?

Thanks,
Ted

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Re: Leica Reichert Jung Polyvar (models)

#47 Post by JWW » Wed Mar 11, 2020 5:53 pm

Thanks for the replies. I haven't been getting notifications of new posting. I've decided to forget the side port for now and fabricate a new top section for the MET and modify it for a full frame camera connection.

-JW:

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Re: Leica Reichert Jung Polyvar (models)

#48 Post by Rorschach » Thu Mar 14, 2024 5:24 am

There's an estimate in this thread that some models of Polyvar originally cost 'tens of thousands of dollars'. Does anyone know more precisely? Perhaps find an original price list. I've read that a fully specced Leitz Aristoplan had a cost of roughly 100 000 USD. I wonder what fully specced (DIC & fluorescence) biological Polyvar cost in the late 80ies?

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Re: Leica Reichert Jung Polyvar (models)

#49 Post by apochronaut » Thu Mar 14, 2024 2:32 pm

wbutter would know. He indicated to me that he was primarily in sales.
If you look at the economic data of the time and before though, a rough picture can be obtained. At the time of AO's acquisition of Reichert in 1961, the average Austrian worker made 1/3 that of the average worker in the U.S. By 1972, ten years later when the Polyvar entered the scene, the gap had closed to 1/2 and was stable until 1985. This would have made the Polyvar pretty good value for what you got until up to 1990, when the Austrian per capita gdp was equal to that of the U.S. The semi-conducter industry was the main market, that's probably why those dedicated and likely less expensive versions, the Polycon and Polylite 88 came along and I don't know if any of those had biological versions at all.Based on the names, not likely. It would have been hard for those needing a biological model to justify the cost of a Polyvar after about 1985, when a smaller microscope costing much less would do about as well.
1985 is also the year that I heard that Zeiss discontinued the Axiomat, and partially due to cost. It was a similar style of platform but not so oriented towards the electronics industry, since it hadn't really emerged yet in the 10 or so years the Axiomat was available. The Axiomat was high 5 figures according to someone who worked at Zeiss here in Canada. Both the Axiomat and Polyvar would have been cheaper in Europe

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Re: Leica Reichert Jung Polyvar (models)

#50 Post by wabutter » Wed Mar 20, 2024 11:53 pm

PeteM wrote:
Fri Jan 31, 2020 8:03 am
Thanks very much for that, Wayne.

On the chance you might know and have time to reply:

- For a given objective (say, Plan Fluotar or Leica "N") how much improvement, if any, was there from the old black letter DMR Delta optics era versus the newer red letter and HC DMR era? One assumes that while the corrections were handled a bit differently, the optical quality for the bread and butter objectives (rather than the specials that required HC) might be close? Or perhaps something like coatings dramatically improved?

- If an older Leica Plan Fluotar objective has DIC markings (e.g. A,B,C,D) but no "HC" or "HCX" marking can one assume it is Delta era? Or perhaps carried over to HC and not yet marked? More to the point, will the corrections be reasonably good on a newer stand with an "HC" head (and thus HC tubelens and HC eyepieces)? It's not clear to me if these would be more like HCX objectives (OK either way) or not.

- Any thoughts on what changed from the Reichert, the H21 (AO 20) DIC and the Diastar 420 DIC systems? Judging from photos they look very similar. Maybe larger prisms for the Diastar?

- To the extent you've had experience with them or by reputation, what would be some pros and cons of the AO (H21), Reichert (420), Leica (HC), Olympus (UIS), and Nikon (CFI60) infinity DIC systems??

It's terrific that you're able to add to this forum. Thank you.
Looks like I have a bit of catching up to do on this thread.
I am not sure I know how to quantify the improvement in terms of real image quality and other optical properties. The shift from Delta to HC was done for a number of different reason, some of which resulted in significant improvements for special applications. I ahve a Leica Publication that was a explanation and a bit of a marketing tool describing the HCS optics concept. It is 24 pages long boolet, so scanning is time consuming, and a huge file. I am not certain the best way to share that information as well. Does copying and distribution violate copyright laws? Although, in searching the Leica website, I found the article of interest at this link:

https://www.leica-microsystems.com/scie ... icroscopy/
I think you and Phil will find it an interesting read.

Yes, if the objective does not have a HC or HCX designation,it will be a Delta program. As was mentioned, the HC objectives are compatible with the Delta stands, but for optimum image quality, they should be paired with HC eyepieces.

I am not an optical engineer, but regarding the H21 vs the 420 DIC, I would speculate the biggest difference would come from the fact the H21 was a 34mm parfocatity index while the 420 was 45mm. Also the max field number for the H21 was 20mm while the Diastar supported a 22mm FN. That would mean the objective prisms would likely have a different exit pupil point and would also need to support the larger field of view.

Here are some interesting bits of information about DIC. Often it simply gets referred to as Nomarski Interference Contrast. What I understand, is that Nomarski licensed the use of his name to only one company per Country. In the USA it was AO, Germany Zeiss, and Japan Olympus. Austria, was Reichert. I don't recall what Aus Jena did in East Germany nor what Lomo did in USSR. That meant in order for the other major brands to have a competing product they used a different approach. So, Leitz used DIC after Smith, B&L I don't remember offering ad DIC system but may have relied on Hoffman Contrast as an alternative (Phil?), and Nikon use Seramont Interfence contrast method. They all were effective in image formation as you would expect from the major players.

Originally, Normarski indicated that there was to be an individual prism for each objective. Rumor has it he was paid a royalty for each prism so it would make sense that he would specify it. Zeiss 160mm Zeiss scopes used a prism intermediate mount in the nosepeice for each objective. as did Leitz. AO did not offer a DIC system until the H21 an used the Reichert Platform when it was needed. The Zetopan pioneered the Single objective nosepeice method by providine a way to move the objective prism vertically behind the back aperture and then horizontally to adjust from the zero order. Once Olympus move to an infinity platform, they too offered a single objective prism concept.
Because the cost of the prism was quite expensive, DIC was usually found only on Research level instrumentation. One other area was in electronics manufacturing, as semiconductor development was in infancy.
Considering that the Objective and DIC design from Reichert were implemented in the early 70's they are still considered to be the Best DIC in the world by today's standards. Both Biologically and industrially. On top of it, the single objective prism concept streamlined operator use and help control the cost.
As I mentioned above, they all do a credible job in image formation and contrast. Some companies of offered two different shear angles in the objective prism to optimize contrast for different specimens. I would suggest that could be an advantage in some cases depending on the sample.

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Re: Leica Reichert Jung Polyvar (models)

#51 Post by Scarodactyl » Wed Mar 20, 2024 11:55 pm

B&L made at least one DIC system, epi DIC for the balplan. A rare but impressive piece of equipment. The AO epi is also pretty exceptional.

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Re: Leica Reichert Jung Polyvar (models)

#52 Post by wabutter » Thu Mar 21, 2024 12:07 am

JWW wrote:
Thu Feb 27, 2020 2:09 am
Being completely new to the Polyvar MET, what are the best objectives? I assume they made other Fluor's and APO's. My MET came with;

Plan Fluor 50x/0.85 Epi
Plan 20x/0.40 Epi IK
Plan 5x/.0.10 Epi
Plan 2x/0.04

-JWW:
I assume you have the camera controller and power supply for the lamp? The most common interface for a non 4x5 or 35mm camera was via the dual reflex module. the prism you have mounted to the right side of the stand, while the camera was mounted on the left. There were a number of method can combinations that could be used for Bolex 16mm cameras, video cameras and of course later on, digital camera. I'll see if I can find a couple pictures and scan them in.

Later in the Thread there is a question of the difference in the Polyvar SC and Polyvar Met. Optically essentially the same. SC had 6x6 and larger stage platforms and the Met offered a 6x6 for a short time but was usually 4x4 stage. Camera interfaces were different as well depending on the vintage of the SC. Technology in the mid 80's and early 90's moved very quickly so new models of the Polyar for Semi applcation evolved about every 6 months. It was almost wild west like.

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Re: Leica Reichert Jung Polyvar (models)

#53 Post by wabutter » Thu Mar 21, 2024 12:13 am

Rorschach wrote:
Thu Mar 14, 2024 5:24 am
There's an estimate in this thread that some models of Polyvar originally cost 'tens of thousands of dollars'. Does anyone know more precisely? Perhaps find an original price list. I've read that a fully specced Leitz Aristoplan had a cost of roughly 100 000 USD. I wonder what fully specced (DIC & fluorescence) biological Polyvar cost in the late 80ies?
In the mid 70's a Polyvar nicely equipped was in the 45-50k range. A typical Polyvar Met 6x6 was up to 70-80K in the mid to late 80's That drove the development fo the Polylite 66 and 88 that brought the price back into the 40-45K range for production labs.
A fully loaded Polyvar with 35mm and 4x5 or 8x10 poloroid camera would drive the cost up. There was also the Polyvar Spec with a Microphotomter attached that drove the cost up closer to 90-100K

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Re: Leica Reichert Jung Polyvar (models)

#54 Post by wabutter » Thu Mar 21, 2024 12:44 am

apochronaut wrote:
Fri Jan 31, 2020 2:52 pm
All very good information, Wayne. You certainly fill in a lot of gaps. After you help out Pete, with his D.I.C. quest, could you comment on this.

One thing I don't see factored in, is the objective distance to the telan lens. The reference focal length,probably the same referred to in patents as the effective focal length, is from the telan lens principal focal plane to the telan lens focal point, correct? This is then the convergent part of the optical path or that part that mimics the optical path in a fixed tube system. In a system, where the eyepieces are magnifiers only, i.e impart no corrections to the system,this portion of the optical path has a magnifying factor only, dependent on it's length. It is in fact a fixed tube length portion of the system, with the telan lens to eyepiece essentially being an altered version of the objective back plane to eyepiece distance in a conventional microscope.
The infinite part of the optical path is not included in the effective focal length, or the rfl but all of the corrections in a system where the eyepieces have a neutral effect, take place in that portion of the optical path; from the objective front surface to the telan lens back surface, and the distance between those two planes would be of paramount importance to the optical system as a whole? The rfl , really just determines the magnification factor then? Why is the objective to telan lens distance; the true infinity tube length not referenced or talked about in terms of it's overall performance of an infinity system. Is it because the companies all have this proprietary obsession?
In theory, the distance between the back aperture of the objective and the tube lens is not relevant because the image rays are runningn parallel. However, in reality this is not completely true a and as the image moves away from the be there is some divergence, resulting in vingetting in the eyepieces. AO realized this as they expanded the dual view systems in to 3,4,5 headed microscope. As a temporary fix, they installed 15mm field stops in the eyepiece. the long term fix was development of a 5 headed bridge that only required the height of a standard dual view bridge.
Moving forward to the Leica modern day platform, The DMR has the Tube lens in the stand and does not move its position relative to the Viewing tube. The Dm L and later version of the DM 1K to 6K all had attachable tubes. If you look at the full description of the tubes and intermediate accessory such as Pol analysers, ergo spacers, dualview bridges, you will see some information that take explaining.
On the tube after it describes the device such as "Trinocular Pol tube HC L 3TP 4/5/7 " The first part is self explanatory, The L disignates for the L platform, 3 means the number of prism positions, and the 4/5/7 reflect the height index 4 in the first position supports a 25mm FN eyepiece, the 5 is 22mm FN the 7 supports a 20mm FN. All intermediate image components, those that mount between the objective ba and the tube lens. had a corresponding height index number and and supported FN in their description as well
A Dueal view bridge has a height indes of 3/25 so it will support a 25mm FN. The ergo spacer is 2/25, drawing attachment 3/20. Each height index number is equal to 15mm. So if you were to stack a dual view bridge with and ergo spacer you would have a height index of 5, so the max FN eyepiece you could use with that combination would be 22mm.

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Re: Leica Reichert Jung Polyvar (models)

#55 Post by Scarodactyl » Thu Mar 21, 2024 1:10 am

Btw I wanted to say thanks again for sharing your unique insights on all this.

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Re: Leica Reichert Jung Polyvar (models)

#56 Post by apochronaut » Thu Mar 21, 2024 2:01 am

Jena and Lomo may have used systems modelled after Pluta. I don't know if Pluta had the same kind of patent protection that was possible in the west at the time.Certainly PZO used a Pluta system but he developed it at PZO. I believe he was a colleague of Nomarski and may be more responsible for the development of interference contrast than he is given credit for.
I actually have the B & L epi DIC prism. Had two but I passed one on to a forum member for 150.00. I do not yet have the illuminator to go with it but do have the epi nosepiece . The other member, somewhat lapsed member, does. Maybe he can report on it's efficacy. It is a nicely made piece.

Thanks for the info., Wayne. Always useful and authoratative.
I am curious about the term " supported "? Do you mean the F.N. at the field stop in the eyepiece or the image circle of the objective or the maximum f.n. of the optical tube?

In looking at the patents of a number of Arthur Shoemaker's objective designs , it seems that the target was 24mm. Most of the designs were but that was never possible as an actual performance specification in the various models. The field stop if a #176 eyepiece allows a 19mm field, and a #180 and 181, a 20mm field. An AO 10 is stretched at 19mm, especially when components are stacked in the infinity space. Alignment has to be uber precise, with a relatively narrow telan lens of only 15mm diameter. In the series 100 and 400 , they increased that to a 20mm clear aperture.
Wondering about that term, supported.

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Re: Leica Reichert Jung Polyvar (models)

#57 Post by wabutter » Thu Mar 21, 2024 3:34 am

When I reference the FN, I am referring to the field stop diameter of the eyepiece. If you had a 1x objective, with a FN eyepiece of 20mm, you would be able to observe a stage micrometer field of 20mm, if the objective was a 2x, the sample are viewed would be 10mm. It is just as important that the rest of the optical system is able to support that field of view without vignetting. So when referencing “supporting” I mean even though the eyepiece FN is the physical limiting factor, the rest of the system must support achieving that value.
Hope that clarifies.

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Re: Leica Reichert Jung Polyvar (models)

#58 Post by PeteM » Thu Mar 21, 2024 4:23 am

Thanks for all that additional information, Wayne.

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Re: Leica Reichert Jung Polyvar (models)

#59 Post by JWW » Thu Mar 21, 2024 5:38 am

Thanks for all the information Wayne it's all appreciated.

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Re: Leica Reichert Jung Polyvar (models)

#60 Post by apochronaut » Thu Mar 21, 2024 8:28 pm

wabutter wrote:
Thu Mar 21, 2024 3:34 am
When I reference the FN, I am referring to the field stop diameter of the eyepiece. If you had a 1x objective, with a FN eyepiece of 20mm, you would be able to observe a stage micrometer field of 20mm, if the objective was a 2x, the sample are viewed would be 10mm. It is just as important that the rest of the optical system is able to support that field of view without vignetting. So when referencing “supporting” I mean even though the eyepiece FN is the physical limiting factor, the rest of the system must support achieving that value.
Hope that clarifies.
I wanted to clarify that. So the final arbiter of the F.N. is the field stop, unless the field stop exceeds the diameter of some other part of the optical tube.
However, it is a base 10 system. The F.N.s of 15X eyepieces can seem illogicsl because a 15X eyepiece with an F.N. of 16 can have s larger field of view than a 10X eyepiece with an F.N. of 20, yet a smaller field viewed. I.e. a larger diameter field stop but smaller diameter of field viewed through it.

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