Search found 6272 matches

by apochronaut
Fri Mar 22, 2024 1:48 am
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 88
Views: 34596

Re: Leica Reichert Jung Polyvar (models)

I am trying to do the math and it doesn't work for me. IF you used a 1x objective with a 16mm FN , 15x eyepiece and put a stage micrometer in place, you would observe a 16mm FOV at 15x. If you put used the same objecive with a 10x/20mm FN, you would see a 20mm FOV at 10x. The object would appear to...
by apochronaut
Fri Mar 22, 2024 12:59 am
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 88
Views: 34596

Re: Leica Reichert Jung Polyvar (models)

I made some images of a stage micrometer through the various 10X W.F. eyepieces used from the AO series 4 up to the common one used in the ATC 2000. I also included the recommended eyepiece used in the Stereostar 580. This provides an actual measure of the F.N. of each eyepiece, as measured. I would...
by apochronaut
Thu Mar 21, 2024 8:28 pm
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 88
Views: 34596

Re: Leica Reichert Jung Polyvar (models)

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 ...
by apochronaut
Thu Mar 21, 2024 7:53 pm
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 49
Views: 2090

Re: Polylite SC endusers(?)

I am interested in knowing what the field capture is and what measurements you used . Telan lens to eyepiece and eyepiece to sensor
The test shot looks good.
by apochronaut
Thu Mar 21, 2024 2:01 am
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 88
Views: 34596

Re: Leica Reichert Jung Polyvar (models)

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 ...
by apochronaut
Tue Mar 19, 2024 4:42 pm
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

Of course it is the environment.
by apochronaut
Tue Mar 19, 2024 3:04 pm
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

Yes but no. That is obviously a technique used and it has to be done under magnification but there is no such possibility to then install the lens and seal out particles until the next time the lens is conveniently removed and if contamination of the sensor occurs, easily recleaned. . Assembly of an...
by apochronaut
Tue Mar 19, 2024 12:47 pm
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

A blower or even compressed air won't remove some. The best I've found for photo optics seems now sold close to hair driers... sorry for this... sold as retractable brushes for makeup. One of my preferred accessory in my photo bag. Most or all dust particles quickly getting away. As it is retractab...
by apochronaut
Tue Mar 19, 2024 3:03 am
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

I've cleaned a lot of lenses. Seems that particles do cling with a charge. A blower or even compressed air won't remove some. I eventually get them clean but I have a feeling a discharge might help. It's multiple locations.
by apochronaut
Mon Mar 18, 2024 9:03 pm
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

They do both apparently. The lever or trigger produces a positive polarity on the in stroke followed by a negative polarity on the return stroke., by compressing Piezo-electric crystals. Their origin goes back to their use in darkrooms. Hair dryers go back to their use in bathrooms. I think they wou...
by apochronaut
Mon Mar 18, 2024 9:08 am
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

Thanks. Seems like it could be possibly of value.
by apochronaut
Fri Mar 15, 2024 2:58 pm
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 677

Re: Reichert U.S.A. and Leica. Why the undercorrection?

Here's a shot at summarizing the discussion of eyepiece corrections in a table. There are surely omissions and likely errors. Let me know and I'll update it. . AO, Reichert, Leica eyepiece corrections.png edit. I wrote all this before I saw your pictures but they confirm my suspicions. I don't thin...
by apochronaut
Thu Mar 14, 2024 2:32 pm
Forum: Microscopes and optics
Topic: Leica Reichert Jung Polyvar (models)
Replies: 88
Views: 34596

Re: Leica Reichert Jung Polyvar (models)

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 ...
by apochronaut
Thu Mar 14, 2024 11:27 am
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 677

Re: Reichert U.S.A. and Leica. Why the undercorrection?

Well, I'm still up in the air why the 34mm Buffalo objectives and presumably those from Vienna made for models like the Neovar 2 and the 45mm Vienna objectives have the same corrections but the later 45mm Buffalo objectives don't. In fact I have used 34mm AO objectives on 11mm extensions, 45mm Reich...
by apochronaut
Thu Mar 14, 2024 1:28 am
Forum: Beginner's corner
Topic: What happened to the Leica DMLB?
Replies: 8
Views: 501

Re: What happened to the Leica DMLB?

Wow. You mentioned short sighted. That should be the main title of your post. The big oversight is U.S. foreign policy . Do you thnk Olympus and Nikon emerged from the vacuum they were in to become dominant players or Toyots or Honda , without complicit acceptance by the U.S. gov't? Was it because t...
by apochronaut
Wed Mar 13, 2024 12:17 pm
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 677

Re: Reichert U.S.A. and Leica. Why the undercorrection?

With the series 400, the planachros were 45mm barrel tweaks of the fully corrected 34mm objectives for some of them and really, that is just a matter of lengthening the barrel but they altered the corrections too and designed a group of new planachro and then planfluor objectives on top. They weren'...
by apochronaut
Wed Mar 13, 2024 5:10 am
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 677

Re: Reichert U.S.A. and Leica. Why the undercorrection?

Both design teams had the designs based on a complete correction model at their fingertips. The Reichert Austria wider field designs were 30mm f.n. too.
It seems it was a choice for a technical reason.
With Leica, perhaps it had somerhing to do with Confocal.
by apochronaut
Wed Mar 13, 2024 3:53 am
Forum: Microscopes and optics
Topic: Reichert U.S.A. and Leica. Why the undercorrection?
Replies: 10
Views: 677

Reichert U.S.A. and Leica. Why the undercorrection?

When Cambridge Instruments and Wild-Leitz merged in 1991, thd newly named Leica carried forward an AO design strategy of undercorrecting objectives slightly, then completing the correction downstream in either the telan lens or the eyepieces. Apparently, Leica still does this today. Here is the hist...
by apochronaut
Tue Mar 12, 2024 10:06 pm
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Re: Anti-Static for lenses.

Objectives need be taken apart only if there is de-lamination of cemented lenses or oil seepage into them. Possibly too, if you happen to drop one in your hot chocolate or just as you set your prize red 60MM parfocal giant upside down on the bench, your Chihuahua mistakes it for a fire hydrant. Alig...
by apochronaut
Mon Mar 11, 2024 8:29 am
Forum: Microscopy accessories
Topic: Anti-Static for lenses.
Replies: 26
Views: 1375

Anti-Static for lenses.

Cleaning microscope glass is tricky sometimes because of static. Even compressed air doesn't deal with many stubborn hitchhikers. Has anyone used an ion beam anti-static gun ? Many audiophiles use and swear by them for cds and vinyl records.
by apochronaut
Mon Mar 11, 2024 7:17 am
Forum: Microscopes and optics
Topic: What are these square-lobed 4- and 6-sided screw heads used in the Reichert 410 Microstar IV?
Replies: 9
Views: 2484

Re: What are these square-lobed 4- and 6-sided screw heads used in the Reichert 410 Microstar IV?

Good thing you caught that, Hans. I think it a key for the "I" shaped cover plate cap screws required. .060" is the size.
by apochronaut
Sun Mar 10, 2024 8:33 pm
Forum: Microscopes and optics
Topic: What are these square-lobed 4- and 6-sided screw heads used in the Reichert 410 Microstar IV?
Replies: 9
Views: 2484

Re: What are these square-lobed 4- and 6-sided screw heads used in the Reichert 410 Microstar IV?

Those are larger. The screws on the series 10 head are 6 flute .048". I don't know the McMaster-Carr number. Newman tools not too far from me near Ottawa has short and long Bristol keys. They used to have a facility in Harford Ct. too but it doesn't seem to have an address or phone as of just after ...
by apochronaut
Sun Mar 10, 2024 3:35 pm
Forum: Illumination Techniques
Topic: Epi Kölher illumination and infinity corrected systems
Replies: 7
Views: 574

Re: Epi Kölher illumination and infinity corrected systems

I think also due to the not perfect nature of filaments. Some might wonder why certain scientific bulbs are so expensive. Some of that expense is due to the effort put into matching the filament coil to the illuminator optic. The illuminator optic is trying to convert that filament image which is of...
by apochronaut
Sat Mar 09, 2024 6:39 pm
Forum: Illumination Techniques
Topic: Epi Kölher illumination and infinity corrected systems
Replies: 7
Views: 574

Re: Epi Kölher illumination and infinity corrected systems

The condenser has to focus the diffuse Köhler beam on the object, and at a working distance dependent distance, irregardless of whether the objective is infinity or finity. Interestingly, there are infinity condensers , which were used mostly in older microscopes. When the sun or a remote illuminato...
by apochronaut
Sat Mar 09, 2024 3:04 pm
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 49
Views: 2090

Re: Polylite SC endusers(?)

If I was doing it, I would make a mock up out of cardboard tubing, ABS pipe, sonotube, or something similar to see what the projection comes out like first. A packing tape roll is 48m and wide enough to avoid vignetting and a toilet paper tube might be at the narrower end of the spectrum.
by apochronaut
Sat Mar 09, 2024 9:31 am
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 49
Views: 2090

Re: Polylite SC endusers(?)

What should the measurement be from the eyepiece shoulder to the flange on a 50D? What camera are you using? I don't recall. -JW: Eyepieces are all different in height from their mounting shoulder to the eyelens or projection surface, so I don't use the eyepiece shoulder as the beginning point for ...
by apochronaut
Sat Mar 09, 2024 12:11 am
Forum: Microscopes and optics
Topic: How to use the AO10 Teaching Head
Replies: 9
Views: 464

Re: How to use the AO10 Teaching Head

There is a little flange on the bottom of the bulb that it pushes up to yo install. If you can grip that, it should just pull out.
by apochronaut
Sat Mar 09, 2024 12:03 am
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 49
Views: 2090

Re: Polylite SC endusers(?)

I was wondering about the depth of that big camera. I thought maybe 20mm. Mirrorless are a lot less : 15mm or so. With the 10X eyepiece you will have to use a shallow Canon bayonet to M42 female and the shallowest helical focuser of that type which is 12mm to 17mm or something in that range. It woul...
by apochronaut
Fri Mar 08, 2024 8:46 pm
Forum: Microscopes and optics
Topic: Polylite SC endusers(?)
Replies: 49
Views: 2090

Re: Polylite SC endusers(?)

I did fo a quick measure on one of my infinity 7 1/16"/182mm systems and with the 19mm f.n. photo eyepiece sitting parfocal in the 182mm rube, my APS-C 23.5mm sensor sits 58mm above the top of the eyelens. You are projecting a 24mm field to a sensor very close to the same size, so you are going to h...