MicrobeHunter.com Microscopy Forum

Your last image is actually quite ok. You might turn up the light further if this is possible. To see the diatoms better you could go two ways: Watch bigger diatoms :D or use a stronger objective. It always is an advantage to have the right density of obects on the slide. Enough space so they don't ...

The only place to put additional spacers would be between rack and dovetail. The rack would be closer to the cog and so there would be some additional friction. Zeiss used aluminium foil, e.g. 0,03mm. It is more important not to remove or crumple any existing foil strips. Probably cleaning and greas...

Your water layer might be too thick. You can remove some water by drawing it out with a piece of cloth.

There is a 6,3 NPL Fluotar too. With Leitz it is a bit difficult with the fields of planar view. Over the decades there were Pl, PLAN, PL, NPL, PL APO, PL FLUOTAR... and they are all different, logically named only in comparison to their contemporarys. Holger Adelmann wrote once in german mikroskopi...

Hello together, I opened this thread to continue the dark field discussion from the thread http://www.microbehunter.com/microscopy-forum/viewtopic.php?f=28&t=5751 . ebay Germany: I think there is just one ebay but you reach it over different URLs. You can search US-Ebay from german ebay and vice ver...

To stop hijacking this beginners thread I opened a new one exclusively for dark field illumination:
posting.php?mode=post&f=28

Bob

Apart from the dirt - the ring around the lens looks very rough. Is this just an opticalillusion or is the surface that uneven? The barrel and the lens fitting of an objective is part of the performance. If it is that roughly made outside I would expect the worst on the inside.

I'm not shure about the optical properties of the scratches in your test slide. They may scatter the light that passes through. Perhaps you can post a comparison of images of the two test slides, taken with the same exposure, one inverted. In an ideal world the images would look the same.

I wouldn't care about white balance too much. If it is somewhat off in a certain image I would adjust it afterwards in the editing software. To me your camera adaptation looks good. Even lighting and no hotspot and a good use of the image circle. In your third image there are diagonal streaks over t...

I think it depends on why you would look at the slides. If it were you profession to detect these bacteria I would strongly recommend the slides. As an amateur you could take what you like. With bacteria images would be enough for me as they are too small to see much of their structure in the light ...

You can find many Zeiss Jena documents and some Zeiss West documents here: http://www.mikroskop-online.de/Zeiss%20Jena%20BDA.htm The history of Carl Zeiss company is probably among the most exciting company histories of all time. From what I remember from reading about it, Jena was to go to the russ...

You could look for this instrument here:
http://www.mikroskop-online.de/Zeiss%20 ... eraete.htm

Hi Radazz, thank you for showing these nice microscopes. With the binocular tubes they must have been very modern for their time. With your sister couple I can imagine that the one with inclined tubes was just so much more ergonomic that it stayed in use for longer. I have some old power tools and o...

Hi Jomaiz,
the Pentax Q7 and Nikon One J1-5 with their fast standard lenses are nice micro cameras to use above the eyepiece. Few people are happy with their eyepiece cameras for long.

Bob

Thank you for showing this interesting instrument! I live in Germany but have never seen such a microscope on german ebay or elsewhere. Heidelberg is an old university city but I don't think that there ever was an optics company in Heidelberg. The stand looks much more like american BL stands than l...

I opened a new topic on the LOCA mount for Radiolaria to avoid mixing things up: viewtopic.php?f=10&t=5565

Bob

Hi together, a while ago I got ready-to-use cleaned fossile radiolaria from Barbados. I began to think about what mountant I should use to make slides from this material. A high refractive Index is not necessary for radiolaria. Some radiolaria are quite big so this won't be a very thin preparation. ...

Hi Hobbyst46, I have not tried the measuring methods myself but I'm shure Mr. Rosenfeld has. If we could narrow the problem down I could ask him when I see him next time. The refractive index of CBO can be found here: https://www.sigmaaldrich.com/Graphics/COfAInfo/SigmaSAPQM/SPEC/W2/W229105/W229105-...

Hello Hobbyst46, here: http://www.mikrohamburg.de/Tips/DER%20BRECHUNGSINDEX.pdf you can find a method for determining refractive indices. It's written in german but you probably can use googel translator on it. For unknown reason its the most downloaded document of our site. For a practical test you...

For dark field you want a hollow cone of light. The outer angle so that the back lens of the objective is fully used. Your dark field spot has to fit to the objective, it is not influenced by the field diaphragm. One part of setting up a Köhler illumination is focusing the condenser on the field iri...

Hi Matt, I think Suphots method will help to show here problems are. Microscope illumination with low power objectives is often only improvised to get along with the standard condenser, so dark field methods will be different in this case. If you are interested in the theory behind it you might habv...

With Zeiss microscopes everything is easy and straightforward! You just have to keep Zeiss Oberkochen and Zeiss Jena apart, each with several different series of stands and optics. :mrgreen: There is no cheating, it stays difficult. On the other hand side you can today get great used Microscopes of ...

My recommendation was less an internet site but more a group of people who actually meet in person. In microscopy you often need very special chemicals and materials in small amounts and for a beginner its also not easy to learn the basics just from a book. The immersion oil is part of the optical c...

You might have a look whether your calibration slide has a cover glass over the actual scale. Your test wouldn't be very useful if you test an objective for 0,17mm cover glass thickness with an unvovered calibration slide.

Hi John,
in your text there is written " iris diaphragm". Is this ring the control for the diaphragm?

Bob

As far as I know parfocality is also influenced by the choice of eyepiece. So maybe this slight parfocality issue will improve with other eyepieces. You can check if parfocality improves if you lift the eyepiece by 5mm within the tube. @zzffnn: Do you know the thicknesses of the parfocality rings? 2...

By sometime into the 60's, the need for compensating eyepieces evaporated. The original problems associated with achieving corrections within an apochromatic objective were overcome by the access to improved low dispersion glass formulas, so from that point forward both achromats and apochromats co...

Lomo, Zeiss West and Zeiss Jena were 160mm tube length. Zeiss West had the meeting point with the eyepiece 10mm in the tube, Lomo and Zeiss Jena 12.5 or 13 mm. The connecting point between head and stand could be somewhat different between these systems. So yes, the tube length might be wrong now. W...

The old Lomo stuff like the Biolam was a close copy of the Zeiss Jena stuff from 1945. The russians actually removed the whole Zeiss works from Jena and continued to produce on the old machines. For the old infinity Zeiss Jena microscopes the PK eyepieces were the plan compensating ones. Chromatic c...

The binocular head is actually from Carl Zeiss Oberkochen, West Germany. Can you post the engravings of the objectives? They seem to be something special. May be from a polarisation microscope. The Biolam is a simplyfied copy of the Zeiss Jena LG stand. The normal Zeiss Jena objectives have nearly t...