Search found 2585 matches

by Hobbyst46
Tue Apr 28, 2020 8:10 pm
Forum: Miscellaneous
Topic: Luminescent dinoflagellates
Replies: 3
Views: 597

Re: Luminescent dinoflagellates

Very interesting and beautiful.

Reminds me of the blueish light liquid in the Selenite tunnels on the moon (H. G. Wells, First Men on the Moon). Perhaps Wells imported the natural phenomenon into the novel...
by Hobbyst46
Tue Apr 28, 2020 3:35 pm
Forum: Introduce yourself
Topic: Greetings from Frankfurt
Replies: 28
Views: 1491

Re: Greetings from Frankfurt

@jemarch Delamination can be expected in old Zeiss objectives as well as eyepieces, according to my somewhat limited experience. A delaminated eyepiece is fairly easy to detect: when normally fitted on the microscope, and a 10X objective in place, brightfield, a fairly empty field of view (say, a sm...
by Hobbyst46
Tue Apr 28, 2020 1:27 pm
Forum: Introduce yourself
Topic: Greetings from Frankfurt
Replies: 28
Views: 1491

Re: Greetings from Frankfurt

Congratulations. Appears to be very nice. Both coarse and fine focusing, and a condenser. Also, a modern on-off and dimmer, instead of the original outdated power supply. If it was never used, I would carefully inspect all mechanics when received - first thing to do. Focusing - coarse and fine, stag...
by Hobbyst46
Tue Apr 28, 2020 12:56 pm
Forum: Pictures and Videos
Topic: Micro stonemasons. Difflugia.
Replies: 21
Views: 1642

Re: Micro stonemasons. Difflugia.

Extremely beautiful images!
Please, some more details about the technique: illumination, stacking, post-processing... thanks in advance!
And a question: given that the structures are quartz - are they colored under polarized light ?
by Hobbyst46
Tue Apr 28, 2020 8:36 am
Forum: Beginner's corner
Topic: Need advice buying a Reichert Microstar IV
Replies: 23
Views: 1623

Re: Need advice buying a Reichert Microstar IV

What is the opinion about the (I have noticed it only recently) seller statement about returns:
"Buyer pays for return shipping" ?
I assume that eBay consider this a valid sales condition ?
by Hobbyst46
Tue Apr 28, 2020 6:53 am
Forum: Pictures and Videos
Topic: Epi-Fluorescence Microscopy and Deconvolution
Replies: 12
Views: 1379

Re: Epi-Fluorescence Microscopy and Deconvolution

Thanks RobBerdan. I will try to deconvolute images that I have collected with ImajJ.
For diatoms, the highest RI available is the choice anyway, for all illuminations.
by Hobbyst46
Mon Apr 27, 2020 9:52 pm
Forum: Pictures and Videos
Topic: Epi-Fluorescence Microscopy and Deconvolution
Replies: 12
Views: 1379

Re: Epi-Fluorescence Microscopy and Deconvolution

A very nice article (in the link), and a comprehensive and easy to read description of fluorescence microscopy. Thanks for posting. May I place some questions and notes. 1. note: In epi-fluorescence, the objective serves a dual purpose - a condenser as well, hence the dependence of brightness on the...
by Hobbyst46
Mon Apr 27, 2020 9:12 pm
Forum: Identification help
Topic: What on earth is this?
Replies: 7
Views: 1146

Re: What on earth is this?

Thanks! ....Any idea why they have evolved to join at the corners? And why does it go roughly from bigger to smaller? Are new members born exclusively at one end and die excludively at the other? Links about their lifecycle? Indeed some Tabellaria images on the web look like yours, although the siz...
by Hobbyst46
Mon Apr 27, 2020 6:07 pm
Forum: Illumination Techniques
Topic: Resolution comparison between BF, Oil DF and PhC
Replies: 7
Views: 740

Re: Resolution comparison between BF, Oil DF and PhC

Very nice job! the DF is particularly excellent !
Please, details about the slide - self made ? how were the diatoms cleaned ? which mounting medium ?
by Hobbyst46
Mon Apr 27, 2020 1:39 pm
Forum: Identification help
Topic: What on earth is this?
Replies: 7
Views: 1146

Re: What on earth is this?

A very nice and intriguing view.
by Hobbyst46
Mon Apr 27, 2020 7:21 am
Forum: Beginner's corner
Topic: X40,x60,x100 objective différence in use
Replies: 15
Views: 1581

Re: X40,x60,x100 objective différence in use

deBult wrote:
Mon Apr 27, 2020 7:16 am
The role of the eyepiece was in the next blog article:

http://bettermicroscopy.blogspot.com/2019/11/
Thanks for point that out. So I only read the first part of the sharpness index blog presentation and did not go further...
by Hobbyst46
Mon Apr 27, 2020 6:51 am
Forum: Beginner's corner
Topic: X40,x60,x100 objective différence in use
Replies: 15
Views: 1581

Re: X40,x60,x100 objective différence in use

At first, the "sharpness index" seemed to me a "figure of merit", a feature that AFAIK is not of much concern in microscopy. But some math reveals more. What the blogger calls the "Sharpness index" can be related to the total useful magnification as follows. Call the sharpness index S. It is defined...
by Hobbyst46
Sun Apr 26, 2020 8:52 pm
Forum: Specimens, samples and slides
Topic: Making long-lasting slides
Replies: 3
Views: 1177

Re: Making long-lasting slides

I have some great specimens of algae with diatoms. Is it possible to preserve these? How? How do you use nail polish in making permanent slides? I doubt that nail polish is appropriate as mountant for slides of alga and diatoms. Nail polish does not mix well with water. Hence, the alga specimen mus...
by Hobbyst46
Sun Apr 26, 2020 1:48 pm
Forum: Pictures and Videos
Topic: Elastic Stentor
Replies: 7
Views: 885

Re: Elastic Stentor

Great video!
by Hobbyst46
Sun Apr 26, 2020 1:45 pm
Forum: Microscopes and optics
Topic: 40x SPlan woes
Replies: 53
Views: 3762

Re: 40x SPlan woes

Pretty new to taking pictures with a microscope myself: so for what it is worth a "comparison" sample here of a Diatom slide. Set-Up as described in previous mail: BH2, SPlan 40, L-tube, NFK 2.5, standard condensor though, Chinese OM-2-Micro-four-thirds adapter and an Olympus E-PL6 camera Feed Back...
by Hobbyst46
Sat Apr 25, 2020 5:48 pm
Forum: Beginner's corner
Topic: X40,x60,x100 objective différence in use
Replies: 15
Views: 1581

Re: X40,x60,x100 objective différence in use

So by the way, May I ask what is the real necessity to have 100x for example when a 63x reach the same n.a ? The resolution is determined by the NA of the objective. In addition to the working distance, depth of focus etc: A higher magnification means that a larger portion of the field of view is o...
by Hobbyst46
Fri Apr 24, 2020 9:45 pm
Forum: Beginner's corner
Topic: Advice on Olympus BH2 with missing components
Replies: 11
Views: 891

Re: Advice on Olympus BH2 with missing components

Alex, PeteM's response above made me take another look. That BHTU scope has a 3.3X NFK photo eyepiece in the phototube. Valuable !
by Hobbyst46
Fri Apr 24, 2020 8:37 pm
Forum: Beginner's corner
Topic: Advice on Olympus BH2 with missing components
Replies: 11
Views: 891

Re: Advice on Olympus BH2 with missing components

Alexg, The eBay microscope shown in the link is not the top model of the BH-2 series, but in general, BH-2 are very good, not just for beginners. And it IS trinocular, although under $500. BH-2 are system microscopes and can be expanded to include phase contrast, for example. The DPlan objectives ar...
by Hobbyst46
Fri Apr 24, 2020 1:48 pm
Forum: Microscopes and optics
Topic: Microscope advice!
Replies: 14
Views: 1051

Re: Microscope advice!

The pandemic situation may bring fresh blood into health systems. I believe, that many new research projects and clinics will be funded, and many new up-to-date microscopes will be purchased by laboratories. That means that older microscopes will have to be thrown to the "surplus" sections and sold ...
by Hobbyst46
Fri Apr 24, 2020 9:54 am
Forum: Beginner's corner
Topic: Specimen ethics
Replies: 42
Views: 2928

Re: Specimen ethics

As above -- a similar question was asked a while ago, with multiple answers. You might search for it. I suppose there is a tendency to anthropomorphize these critters. My only reasonably sure belief it that what you wouldn't want to do is introduce it to different place - where it might be more a c...
by Hobbyst46
Fri Apr 24, 2020 8:28 am
Forum: Beginner's corner
Topic: Also Needing Microscope Purchase Advice
Replies: 35
Views: 1627

Re: Also Needing Microscope Purchase Advice

Also on the Optiphot, the lamp housing is made of plastic and is fragile. I once fixed a broken lamphouse with high-quality epoxy cement. Used it liberally, like casting, and supported the broken part for 24 hours. The epoxy is now stronger than the original plastic...
by Hobbyst46
Fri Apr 24, 2020 8:14 am
Forum: Pictures and Videos
Topic: Amphipleura pellucida
Replies: 10
Views: 815

Re: Amphipleura pellucida

...I was never able to get achieve a useful level of oblique illumination but I could try something similar to what you did with the darkfield (not with an ultracondenser though) The D darkfield position on the Zeiss turret condenser, when oiled to the slide, provides nice darkfield, fairly close t...
by Hobbyst46
Thu Apr 23, 2020 11:47 am
Forum: Beginner's corner
Topic: From New Zealand & new to microscopy
Replies: 6
Views: 576

Re: From New Zealand & new to microscopy

Nice start ! enjoy ! I think, this is not the thinnest possible onion skin. Perhaps it folded in two during mounting. It is possible to peel just a single layer of cells. It is often easier to peel it from the inner side of the crecent-form onion slice, rather than from the outer surface. I take a 5...
by Hobbyst46
Thu Apr 23, 2020 6:24 am
Forum: Microscopes and optics
Topic: 40x SPlan woes
Replies: 53
Views: 3762

Re: 40x SPlan woes

OK... here is calibration slide video with the OEM photo tube, GH4 Panasonic Camera: https://www.youtube.com/watch?v=FXMqjLceWuI&feature=youtu.be My current theory is that I had dirt in my projection eyepiece (on and between the two lenses) and after cleaning it, my microscope is performing normall...
by Hobbyst46
Wed Apr 22, 2020 7:46 pm
Forum: Camera systems and imaging
Topic: (BH-2) Any solutions for widefield (26.5mm) photography?
Replies: 27
Views: 1574

Re: (BH-2) Any solutions for widefield (26.5mm) photography?

Since I'm going to be using all SWHK eyepieces for this, I am not sure if it actually will be afocal. They allow focal adjustment inside the eyepiece from +2 to -8 (not sure what units, but that's how it's labeled on the eyepiece.) And I'll be going for parfocality between two of them, so it's seem...
by Hobbyst46
Wed Apr 22, 2020 3:53 pm
Forum: Pictures and Videos
Topic: From the Biofilm
Replies: 5
Views: 451

Re: From the Biofilm

I often thought of patiently collecting: 'naturally cleared diatom frustules'...to on some rainy day..set about mounting as fixed/'permanent' slides. Often in enjoyment of collected water samples from outdoor waters...there one is...one huge pennate diatom frustule ( large as a cough drop I will sa...
by Hobbyst46
Wed Apr 22, 2020 3:39 pm
Forum: Beginner's corner
Topic: HELP!! Looking for a new microscope!
Replies: 17
Views: 1076

Re: HELP!! Looking for a new microscope!

Most welcome. Please note that many used microscopes have flaws, and if these are mechanical, repair might be a challenge. That is a risk we take when buying used. You may also want to post a message in the Selling and Buying section of this forum; buying a used microscope that has been tested by a ...
by Hobbyst46
Wed Apr 22, 2020 2:57 pm
Forum: Beginner's corner
Topic: HELP!! Looking for a new microscope!
Replies: 17
Views: 1076

Re: HELP!! Looking for a new microscope!

If one is ready to take a risk, this: https://www.ebay.com/itm/Nikon-Optiphot-Binocular-Microscope-w-4-Objectives/323961976372?hash=item4b6da37634:g:cCoAAOSwdOxdtyZJ The international shipping fare is ridiculous and the scope is not tested, and no returns, but there is a "Make Offer" Much less risk,...
by Hobbyst46
Wed Apr 22, 2020 8:56 am
Forum: Pictures and Videos
Topic: From the Biofilm
Replies: 5
Views: 451

Re: From the Biofilm

Very nice catch ! how did the biofilm form ? a closed prescription bottle is not (AFAIK) an ideal growth environment for plants. Thanks in advance for details.
by Hobbyst46
Wed Apr 22, 2020 7:48 am
Forum: Pictures and Videos
Topic: Pollen Fine Detail
Replies: 47
Views: 3358

Re: Pollen Fine Detail

mrsonchus, thanks for the very nice images !
Would you say that such performance was not possible from your Orthoplan ? talking only about the image itself, not the scope mechanics ?