MicrobeHunter.com Microscopy Forum

OP:

@Hobbyst46
@Microscopy is fun

I now see there is a difference of opinion on AO and PO! (To be continued!)

To try and simplify matters. First, the numerical aperture is a property of the lens AND medium in contact with it. NA = n*sin(alpha), where n is the RI of the medium in contact with the lens. When the medium is air, n=1 to a good approximation. When it is water, n=1.33, etc. Secondly, visibility d...

The ratio between two values which are expressed in the same units will inevitably be 'dimensionless' because it (itself) has no unit of measure ... The units cancel-out in the calculation, RI = Speed of Light in a vacuum divided by Speed of Light in the material Therefore RI is dimensionless By co...

Hi linuxusr, when you talk about imaging of microscopic objects, you need to distinguish between amplitude objects (AO) and phase objects (PO). AOs modify the amplitude of light passing through them by absorbing certain wavelengths of the incident light. POs modify the phase of the incident light w...

we hear that the RI value of air is 1. This value has been rounded down. The actual value is 1.000293 or 1 + 293/10000. Actually 1.000293 = 1 + 2.93 /10000 More importantly, I am trying to understand the two images. They look as if exactly the same field of view is shown. The same region of the hai...

A very interesting post, linuxur … But [at least for comprehension, even if not for our practical purposes], I think we need a good description of Refractive Index as our baseline. It is a dimensionless ratio … which is, of course, why the value for a vacuum is 1 https://spark.iop.org/refractive-in...

@MichaelG @Hobbyst46 @Microscopy is fun Still getting back to you and reading your posts. Your responses are much appreciated. Meanwhile, I messed up and left out the following diagram, then one in which I reference the quadrants. Please re-read that part of my post in reference to this diagram: [me...

The purpose of this post is to invite discussion on Refractive Index (RI) and to understand it in and of itself, as well as its relationship to resolution and the medium and the specimen. Specifically, for the purposes of the labs described here, think of this three part relationship: the RI of glas...

OP: I solved it after playing around with about 25 more iterations: At IMGUR: a. Upper right corner of diagram, hover cursor to get "copy link." To the right will be a drop down menu. b. Copy/paste link from BBCode (Forums) AT MH: a. On new post page, select Media Embed and NOT Insert Image. Paste a...

What I am failing to do I have already done successfully, but each time I forget how to do it. This time I'm completely failing. I will write a steps document so this doesn't happen again. Here's what I've done: 1. I successfully upload and label images to my IMGUR account. I ensure that all images ...

The summary article:

https://phys.org/news/2021-12-evidenc ... ence.html

The original article:

https://www.science.org/doi/10.1126/sci ... wKo.mailto

OP Summary: The results of this lab, comparing the efficacy of various mountants on the observation of cheek cells, was anti-climactic. Essentially, it doesn't matter which mountant you use, or none, for the morphology you observe will be the same. In all cases you can observe the shape of the cell...

Introduction It’s easy to see why this is a common lab because the sample is ready to hand, easy to prepare, and one can in minutes observe a eukaryotic cell and nucleus! But is that all? I find it disappointing that most YouTube videos--I’ve watched about ten—do not explore further. So that is wha...

Thanks for your sentiments and possible solutions, everyone. Thanks zzffnn for your offer. Meanwhile, I called Zeiss in NY, U.S. The phone help was very sympathetic and game me an address to write to. I did that and also attached my invoices of Zeiss equipment purchases, totaling around $5,000.00. I...

You could pick a relevant company name, register the domain, and find a low cost provider to host it and your new email system. Some reliable providers, such as "Go Daddy" in the US, offer fairly cheap registrations and hosting services. Sadlly, Zeiss is not alone in actively discouraging "time was...

Hello All, I need to see if my Axiocam 208 needs an update in its firmware. So, I write the version number of what I currently have, then go to the Zeiss website to identify the current firmware version number. But it's not stated. Instead, I have to download the file. Only then will I know if I alr...

Happy Holidays Everyone!

Come on Zeiss people! Anyone using ZEISS ZEN Lite (Blue) software? No point in me posting comment/questions if I'm the only one using it!

If you need a μ to write μm, and you'd rather not take the easy way and write um, then go to https://www.greekalphabetletters.com and copy/paste!

Every time I drop a slide, teeming with life, in my bleach jar, I feel pangs of remorse! This is as it should be as our specimens are distant kin: a. We are composed of the same structural unit, the eukaryotic cell, b. We share some identical biochemical processes, ATP metabolism, c. We share stimul...

Hi, my name is Jürgen, I am 46 years old and used to work as a graphic designer. Not anymore because i got struck with cancer and am now, very slowly, in a healing process. My profession now is to be a patient. After purchasing an industrial inspection microscope and happily playing around with it,...

Hi, I am quite late with my introduction, have already had some profit from this wonderful knowledge base. I am 59 and I live in Duisburg (Germany). I have returned to microscopy after many, many years after selling my astronomy equipment due to light pollution in my area, too few clear nights that...

Hello, everyone. My name is Cathy. I live in a small town in Vermont. I've always been interested in science, and took an elective in Field Biology that gave me some hands-on sample collecting experience with an excellent professor. But majoring in engineering, I couldn't put much time into biology...

smollerthings wrote: ↑

Fri Nov 05, 2021 12:44 pm

In my sea of ascorbic acid, entire islands are built and destroyed in a matter of minutes

Interesting. What is your recommendation for first time preparation of ascorbic acid? What property of ascorbic acid makes it amenable to LM? Are they crystals?

OP: I read with interest your various methods for measuring this value. Some of those methods were too sophisticated for this amateur! -- The Zeiss spec indicates a 15 mm stage lift. I set my caliper to 15 mm, held it against a cutting board perpendicular to the stage, with the bottom jaw flush with...

@ et al Hello All: OP Summation: I did not have success calibrating my FF knob such that the distance I turned it agreed with the distance of the Z axis between the top and the bottom of a coverglass. More on that later. The data: (a) The Zeiss spec for the FF knob is 0.5 mm rev. or 500 μm/rev. Earl...

A simple check is to take a cover slip and make a line on the top an bottom with a permanent marker. Only accurate enough as he cover slip thickness but useful to determine whether one has calulated right. In engineering literature one has to be careful to avoid mixing up dimensions, are we talking...

BramHuntingNematodes wrote: ↑

Mon Nov 08, 2021 8:29 pm

There is a Zeiss Primostar 3 in the signature line. I suppose there may only be 100 increments if each increment is 2 and the range is between 0-200.

There's 200 numbered increments but each as the value of 2: 2, 4, 6, 8, etc.

You may also be able to find the information in the microscope’s user manual. If you need to be sure of accuracy, I recommend calibrating it using a broken coverslip to see how many graduations of the fine focus knob it takes to get from the lower surface to the upper surface of the coverslip using...

. Looked it up out of interest. This is from the Zeiss Primostar 3, 25 page brochure 500/200 = 2.5µm by my calculation, so each division would be 5µm . 75RR, you are on the money! Thanks. As many times as I read the manual, I never saw this. I repeated your calculations and arrived at the same valu...