Search found 30 matches
- Wed Mar 14, 2018 9:37 am
- Forum: Specimens, samples and slides
- Topic: My First Diatom Hunt
- Replies: 18
- Views: 9214
Re: My First Diatom Hunt
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 ...
- Tue Mar 13, 2018 12:26 pm
- Forum: Microscopes and optics
- Topic: Asking for help - fixing/alignment of a Zeiss condenser rack
- Replies: 5
- Views: 3475
Re: Asking for help - fixing/alignment of a Zeiss condenser rack
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...
- Wed Mar 07, 2018 4:09 pm
- Forum: Beginner's corner
- Topic: I’m struggling to have a closer look at Rotifers.
- Replies: 18
- Views: 9767
Re: I’m struggling to have a closer look at Rotifers.
Your water layer might be too thick. You can remove some water by drawing it out with a piece of cloth.
- Wed Mar 07, 2018 3:37 pm
- Forum: Microscopes and optics
- Topic: 4x or 5x for a Leitz Dialux 20 EB
- Replies: 9
- Views: 5300
Re: 4x or 5x for a Leitz Dialux 20 EB
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...
- Thu Mar 01, 2018 11:07 am
- Forum: Illumination Techniques
- Topic: Dark field illumination: Questions and answers
- Replies: 65
- Views: 38262
Dark field illumination: Questions and answers
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...
- Thu Mar 01, 2018 10:35 am
- Forum: Illumination Techniques
- Topic: 43x very dim
- Replies: 38
- Views: 17900
Re: 43x very dim
To stop hijacking this beginners thread I opened a new one exclusively for dark field illumination:
posting.php?mode=post&f=28
Bob
posting.php?mode=post&f=28
Bob
- Thu Mar 01, 2018 10:12 am
- Forum: Microscopes and optics
- Topic: New objective dusty inside... Amscope poor quality control
- Replies: 15
- Views: 6749
Re: New objective dusty inside
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.
- Sun Feb 25, 2018 1:15 am
- Forum: Camera systems and imaging
- Topic: Experiments with afocal photomicrography: illuminations, spider threads...
- Replies: 53
- Views: 29704
Re: Experiments with afocal photomicrography: illuminations, spider threads...
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.
- Sat Feb 10, 2018 11:22 pm
- Forum: Camera systems and imaging
- Topic: Experiments with afocal photomicrography: illuminations, spider threads...
- Replies: 53
- Views: 29704
Re: Experiments with afocal photomicrography: illuminations, spider threads...
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...
- Fri Feb 02, 2018 10:55 pm
- Forum: Specimens, samples and slides
- Topic: Slides of pathogens
- Replies: 8
- Views: 6614
Re: Slides of pathogens
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 ...
- Wed Jan 31, 2018 3:14 pm
- Forum: My microscope
- Topic: Zeiss Jena LG
- Replies: 15
- Views: 9428
Re: Zeiss Jena LG
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...
- Wed Jan 31, 2018 2:38 pm
- Forum: Collecting microscopes and slides
- Topic: I’m not sure this is a microscope....
- Replies: 13
- Views: 8675
Re: I’m not sure this is a microscope....
You could look for this instrument here:
http://www.mikroskop-online.de/Zeiss%20 ... eraete.htm
http://www.mikroskop-online.de/Zeiss%20 ... eraete.htm
- Sat Jan 27, 2018 1:36 am
- Forum: Collecting microscopes and slides
- Topic: Sisters
- Replies: 5
- Views: 4769
Re: Sisters
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...
- Sat Jan 27, 2018 1:17 am
- Forum: Camera systems and imaging
- Topic: Looking for camera
- Replies: 12
- Views: 8281
Re: Looking for camera
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
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
- Thu Jan 11, 2018 8:01 am
- Forum: Collecting microscopes and slides
- Topic: When is a toy stand more than a toy microscope?!
- Replies: 13
- Views: 7436
Re: When is a toy stand more than a toy microscope?!
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...
- Thu Jan 04, 2018 12:25 pm
- Forum: Specimens, samples and slides
- Topic: A new (?) home-made mounting medium for diatoms
- Replies: 46
- Views: 28656
Re: A new (?) home-made mounting medium for diatoms
I opened a new topic on the LOCA mount for Radiolaria to avoid mixing things up: viewtopic.php?f=10&t=5565
Bob
Bob
- Thu Jan 04, 2018 12:24 pm
- Forum: Specimens, samples and slides
- Topic: UV-curing LOCA adhesive for mounting radiolaria
- Replies: 10
- Views: 6391
UV-curing LOCA adhesive for mounting radiolaria
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. ...
- Wed Jan 03, 2018 4:08 pm
- Forum: Specimens, samples and slides
- Topic: A new (?) home-made mounting medium for diatoms
- Replies: 46
- Views: 28656
Re: A new (?) home-made mounting medium for diatoms
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-...
- Tue Jan 02, 2018 8:37 am
- Forum: Specimens, samples and slides
- Topic: A new (?) home-made mounting medium for diatoms
- Replies: 46
- Views: 28656
Re: A new (?) home-made mounting medium for diatoms
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...
- Fri Dec 22, 2017 1:33 pm
- Forum: Illumination Techniques
- Topic: Dark field difficulties
- Replies: 23
- Views: 14818
Re: Dark field difficulties
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...
- Fri Dec 22, 2017 11:13 am
- Forum: Illumination Techniques
- Topic: Dark field difficulties
- Replies: 23
- Views: 14818
Re: Dark field difficulties
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...
- Fri Dec 01, 2017 2:10 pm
- Forum: Microscopes and optics
- Topic: Identification of microscope objectives
- Replies: 20
- Views: 13780
Re: Identification of microscope objectives
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 ...
- Tue Nov 28, 2017 3:12 pm
- Forum: Beginner's corner
- Topic: Starting with identifying a decent microscope
- Replies: 24
- Views: 11427
Re: Starting with identifying a decent microscope
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...
- Tue Nov 28, 2017 10:07 am
- Forum: Microscopes and optics
- Topic: LOMO compensating optics
- Replies: 62
- Views: 23806
Re: LOMO compensating optics
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.
- Sun Nov 19, 2017 10:32 pm
- Forum: Microscopes and optics
- Topic: Just bought Leitz objective...
- Replies: 38
- Views: 13732
Re: Just bought Leitz objective...
Hi John,
in your text there is written " iris diaphragm". Is this ring the control for the diaphragm?
Bob
in your text there is written " iris diaphragm". Is this ring the control for the diaphragm?
Bob
- Wed Nov 08, 2017 5:56 pm
- Forum: Microscopes and optics
- Topic: LOMO compensating optics
- Replies: 62
- Views: 23806
Re: LOMO compensating optics
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...
- Mon Oct 23, 2017 5:49 am
- Forum: Microscopes and optics
- Topic: LOMO compensating optics
- Replies: 62
- Views: 23806
Re: LOMO compensating optics
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...
- Sun Oct 22, 2017 1:21 am
- Forum: Microscopes and optics
- Topic: Lomo work in progress
- Replies: 5
- Views: 3547
Re: Lomo work in progress
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...
- Sun Oct 22, 2017 12:42 am
- Forum: Microscopes and optics
- Topic: LOMO compensating optics
- Replies: 62
- Views: 23806
Re: LOMO compensating optics
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...
- Sun Oct 22, 2017 12:20 am
- Forum: Microscopes and optics
- Topic: Lomo work in progress
- Replies: 5
- Views: 3547
Re: Lomo work in progress
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...