Search found 2381 matches

by MicroBob
Thu Mar 01, 2018 8:54 pm
Forum: Illumination Techniques
Topic: Dark field illumination: Questions and answers
Replies: 65
Views: 18338

Re: Dark field illumination: Questions and answers

Thanks Apochronaut for your detailed information! I looked at two objectives this evening: 1. Cooke 80:1 1,32 Apo Oil with installed darkfield funnel and description 2. Vickers 50:1 1.0 Fluo Oil With the Zeiss Jena pancratic condensor with the cardioid dark field head it did some tests. 1. The Cooke...
by MicroBob
Wed Feb 28, 2018 3:18 pm
Forum: Illumination Techniques
Topic: 43x very dim
Replies: 38
Views: 7374

Re: 43x very dim

The question after the needed LED power for high power dark field came up. I did a test with my Zeiss Jena NF with 10W LED and a 90:1 n.a 1,25-0,8 Zeiss Jena achromat (old design, 33mm length) and two different dark field condensors. First test with a Zeiss Jena cardioid darkfield condenser, unknown...
by MicroBob
Wed Feb 28, 2018 2:51 pm
Forum: Pictures and Videos
Topic: Euglena, Algae, Diatom and Cyano
Replies: 16
Views: 2441

Re: Euglena, Algae, Diatom and Cyano

The camera market was no fun for the makers in the last years. Most of them brought mirrorless systems between 2009 and 2011 but didn't sell very much until 2015. They struggled to find a good compromise between not slaughtering their halfway good DSLR sales and at the same time offering an attracti...
by MicroBob
Wed Feb 28, 2018 6:29 am
Forum: Beginner's corner
Topic: Word to the Wise: Lessons Learned
Replies: 18
Views: 4905

Re: Word to the Wise: Lessons Learned

Thank you for the help with the search engine! This is the correct link to the "Doing Diatoms a Differnet Way" -thread: http://www.microbehunter.com/microscopy-forum/viewtopic.php?t=4227 I guess that it is possible to exclude words from search to reduce server load. In some forums you can't search f...
by MicroBob
Tue Feb 27, 2018 9:02 pm
Forum: Beginner's corner
Topic: Word to the Wise: Lessons Learned
Replies: 18
Views: 4905

Re: Word to the Wise: Lessons Learned

Hi Hobbyst46,
thank you for the recommendation of the two threads. I tried to search for the two threads you recommended. It looks as if "Diatoms" is an illegal search word in this form? 8-)
by MicroBob
Tue Feb 27, 2018 8:53 pm
Forum: Beginner's corner
Topic: Word to the Wise: Lessons Learned
Replies: 18
Views: 4905

Re: Word to the Wise: Lessons Learned

Storing the slides this way has one more advantage: The specimens don't sink down from the cover slip to the slide. This is very important for diatom slides. So storage always flat with cover slip down.

My DIY - ringing table looks very similar. The two disks are guide wheels from an elevator.
by MicroBob
Tue Feb 27, 2018 8:33 pm
Forum: Miscellaneous
Topic: Hoyer's Microscope Slide Mounting Medium
Replies: 5
Views: 3061

Re: Hoyer's Microscope Slide Mounting Medium

The Chloral Hydrate brightens the specimen. This is a quick mountant for small animals. It is only medium permanent. The medium crystalizes often but not always after some time of storage. Here is some more to read: http://www.mikrohamburg.de/Tips/T_Berlesepraeparate.html If you can get hold of Chlo...
by MicroBob
Tue Feb 27, 2018 8:16 pm
Forum: Illumination Techniques
Topic: 43x very dim
Replies: 38
Views: 7374

Re: 43x very dim

From my experience I have nothing to complain about a working LED conversion. With a 10W LED and a cardioid darkfield condenser I get a very good illumination with the oil immersion objectives. Of cause LEDs are not perfect and there are some disadvantages, but for me the advantages are more importa...
by MicroBob
Mon Feb 26, 2018 6:10 pm
Forum: Illumination Techniques
Topic: 43x very dim
Replies: 38
Views: 7374

Re: 43x very dim

There is one further possibility for the dim light: It is an old scope and the bulb may have been changed to a a lower power model that just happend to be at hand. Have a look what is written on the bulb. It might also be a mismatch of bulb and transformer.
by MicroBob
Sun Feb 25, 2018 8:43 pm
Forum: Pictures and Videos
Topic: Sprossquerschnitt einmal anders
Replies: 6
Views: 1124

Re: Sprossquerschnitt einmal anders

Hallo Manfred, vielen Dank fürs Zeigen! Das letzte Foto sieht komplett irreal aus: Man meint, ein Netz vor sich zu haben, das aus bunter Wolle gehäkelt worden wäre! Hast Du eine Idee, wie es dazu kommt? Hier im Forum wird überwiegend in Englisch geschrieben - könntest Du das lesen, wenn ich so geant...
by MicroBob
Sun Feb 25, 2018 4:12 pm
Forum: Illumination Techniques
Topic: 43x very dim
Replies: 38
Views: 7374

Re: 43x very dim

The 43x needs a proper illumination with the condenser. This should be racked up until close below the slide. The condensor aperture should be open or just a little closed. If there is a swing in lens below the condensor it should be out of the way normally (Apochronaut - ist this true for this stan...
by MicroBob
Sun Feb 25, 2018 12:54 pm
Forum: Camera systems and imaging
Topic: Experiments with afocal photomicrography: illuminations, spider threads...
Replies: 53
Views: 15356

Re: Experiments with afocal photomicrography: illuminations, spider threads...

Noberts work was really outstanding at this time. In 1850 the normal person had nearly no possessions that were so finely made that measurments of better than +/- 1mm were necessary. The most precise items at this time that were produced in bigger volume were guns and stearm engines and the machiner...
by MicroBob
Sat Feb 24, 2018 5:42 pm
Forum: Camera systems and imaging
Topic: Experiments with afocal photomicrography: illuminations, spider threads...
Replies: 53
Views: 15356

Re: Experiments with afocal photomicrography: illuminations, spider threads...

Hi Hobbyst46, I would suggest to use an ordinary micrometer slide like this: https://www.ebay.de/itm/0-01mm-Microscope-Stage-Micrometer-Cross-Dot-Calibration-Slide-with-4-Scales/172579169961?hash=item282e8526a9:g:t4sAAOSwol5Yy1O4 Add a cover slip of 0,17mm with a drop of immersion oil and you have t...
by MicroBob
Sat Feb 24, 2018 2:28 pm
Forum: Pictures and Videos
Topic: Euglena, Algae, Diatom and Cyano
Replies: 16
Views: 2441

Re: Euglena, Algae, Diatom and Cyano

Thank you for the hint to Capture One. The work flow you describe sounds very efficient. In the mean time this Sony version has increased in price to now 79€+VAT. I'm a bit worried that they just try to meet some sales goals and will inrease the price further and further. For my cameras I had a look...
by MicroBob
Fri Feb 23, 2018 7:53 pm
Forum: Pictures and Videos
Topic: Euglena, Algae, Diatom and Cyano
Replies: 16
Views: 2441

Re: Euglena, Algae, Diatom and Cyano

Thank you for the description of your method! I was so interested about it because it is a long term project of mine to get into photographing moving objects. Your description gave me several new insights about what to do and what to avoid. When you start with a vintage Zeiss Jena NF or Zeiss GFL wi...
by MicroBob
Fri Feb 23, 2018 4:11 pm
Forum: Camera systems and imaging
Topic: Experiments with afocal photomicrography: illuminations, spider threads...
Replies: 53
Views: 15356

Re: Experiments with afocal photomicrography: illuminations, spider threads...

Peter H ö bels work is always very interesting and valuable if you like the technical aspects of microscopy. He often carries out precise measurements on topics that bring an end to controverse discussions that go on and on because there is too much opinion and little certainty. Camera adaptation is...
by MicroBob
Fri Feb 23, 2018 3:15 pm
Forum: Beginner's corner
Topic: What scope for freshwater plankton
Replies: 6
Views: 1720

Re: What scope for freshwater plankton

I would recommend to stay away from these LCD-toy-microscopes. You will be impresse when you use a real quality instrument after this. Plankton is normally watched under a normal biological microscope with 10x to 40x objectives. For a thicker water layer it is possible to apply wax feet on the edges...
by MicroBob
Fri Feb 23, 2018 3:02 pm
Forum: Pictures and Videos
Topic: Euglena, Algae, Diatom and Cyano
Replies: 16
Views: 2441

Re: Euglena, Algae, Diatom and Cyano

Freezing the action is simple with flash. But stacking plankton would need a very stationary object or a very fast camera.
My Nikon 1j5 can take 20 images in 0,33 seconds. It would also be possible to extract the images from a film. But how does hkv do it?
Håkan, show us some of your wizardry!
by MicroBob
Fri Feb 23, 2018 7:08 am
Forum: Pictures and Videos
Topic: Euglena, Algae, Diatom and Cyano
Replies: 16
Views: 2441

Re: Euglena, Algae, Diatom and Cyano

Thank you for these great images! They are stacked shots? With plankton I would expect movement to be a problem. How do you cope with that?

Bob
by MicroBob
Thu Feb 22, 2018 6:43 pm
Forum: Beginner's corner
Topic: AO Series 4 Accidental buy...
Replies: 29
Views: 4205

Re: AO Series 4 Accidental buy...

Dim 40x: Generally the 40x objective give a less contrasty and dimmer image compared to a 10x. They are also much more dependent on a well adjusted lighting and carefully prepared slide. If you are new to microscopy this might astonish you. You can use a reversed eyepiece to check whether the front ...
by MicroBob
Thu Feb 22, 2018 4:25 pm
Forum: Beginner's corner
Topic: Photography related questions for beginner.
Replies: 7
Views: 1969

Re: Photography related questions for beginner.

Hi Shelby, the chinese microscopes are sold under different names depending on the country you live in. There is no doubt that the chinese are able to make good microscopes but it is a bit difficult to identify the better ones and avoid the toy microscopes. Generally it can be said that resale value...
by MicroBob
Wed Feb 21, 2018 5:03 pm
Forum: Beginner's corner
Topic: Photography related questions for beginner.
Replies: 7
Views: 1969

Re: Photography related questions for beginner.

Hi Shelby, to avoid frustration you should be aware that a microscope is not a simple camera accessory that gives you nice images as soon as you connect it to your camera. Microscopy is a wide field and a difficult one too. Microphotography again is difficult for an experienced microscopist. Of caus...
by MicroBob
Tue Feb 20, 2018 8:52 am
Forum: Pictures and Videos
Topic: African sleeping sickness
Replies: 7
Views: 1064

Re: African sleeping sickness

Hi Pat, thank you for showing! It's fine to see that you finally found a source for pathogene slides. From the times of Robert Koch and Louis Pasteur on this was a very important topic for many decades. This was the time when they even made small field microscopes like the Hensold Protami with oil i...
by MicroBob
Mon Feb 19, 2018 8:55 pm
Forum: Beginner's corner
Topic: AO Series 4 Accidental buy...
Replies: 29
Views: 4205

Re: AO Series 4 Accidental buy...

This is a nicely simple and effective design! In its simplicity it even surpasses the mirror adjustment of the rusian LOMO stand I showed a while ago. So if you think you can make something from sheet metal with a bit of accuracy, the job is simple. In the beginning it is a flat piece of sheet metal...
by MicroBob
Mon Feb 19, 2018 7:21 am
Forum: Specimens, samples and slides
Topic: Diatom pictures today - trying to improve res by enhancement techniques 1of2
Replies: 9
Views: 2620

Re: Diatom pictures today - trying to improve res by enhancement techniques 1of2

Some ideas: - Are you using electronic first shutter curtain on your camera? - For Amphipleura pellucida you need all the resolution you can get, so high n.A condenser oiled to the slide - You might try circular oblique lighting - You might use a high n.A. darkfield condenser if you have one, maybe ...
by MicroBob
Sun Feb 18, 2018 7:59 pm
Forum: My microscope
Topic: First microscope, identified! Vickers Instruments Metalette
Replies: 9
Views: 3904

Re: First microscope, identified! Vickers Instruments Metalette

What I meant was this: With the Patolette it is likely to crash the condensor into the objective. This of cause is not possible with your microscope. But with your Metalette it might be as easy to crash the objectives into the table or object lying on the table.
by MicroBob
Sun Feb 18, 2018 4:46 pm
Forum: Pictures and Videos
Topic: Didinium nasatum ciliate
Replies: 9
Views: 1490

Re: Didinium nasatum ciliate

Hi Fancisco,
thank you for showing! It is interesting to see how you Didinium changes orientation between feeding and moving.

I have probably seen this ciliate before, but your video intensified my interest in it.

Bob
by MicroBob
Thu Feb 15, 2018 7:54 am
Forum: My microscope
Topic: First microscope, identified! Vickers Instruments Metalette
Replies: 9
Views: 3904

Re: First microscope, identified! Vickers Instruments Metalette

I have a warning for users of the Patholette. It may also apply to the Metalette. With the Patholette it more likely than usual to grab the microscope by the table and crush the condenser through the slide into the objective. There is not much elso to grab on this stand. The table guides move lightl...
by MicroBob
Mon Feb 12, 2018 8:15 pm
Forum: Microscopy accessories
Topic: Flourite Objectives on Amscope
Replies: 16
Views: 5967

Re: Flourite Objectives on Amscope

Hi Apochronaut, thank you for your thorough testing! I think that many people don't really feel competent enough to buy second hand and for them it is especially interesting to read what is on offer beyond the simple achromats. Your review shows nicely that decades ago very nice optics have been mad...
by MicroBob
Sun Feb 11, 2018 10:34 pm
Forum: Camera systems and imaging
Topic: Halo with reflex
Replies: 8
Views: 6224

Re: Halo with reflex

To me this looks like a reflection in the tube too. You might place a small circular shade there that prevents the light from directliy hitting the inner surface of the tube. Like a small ring within the tube. There is self adhering flocking material availabe that cuts out reflections even better th...