More phase contrast photos of cleaned diatoms
More phase contrast photos of cleaned diatoms
This is a continuation of
viewtopic.php?f=10&t=9079
Further slide surfing revealed a Cyclotella meneghiniana Kutzing (tentative idn.). I was very happy since the Centrales are a rare find. So here are images, one with a 40X0.75 Neofluar (dry), the other with 100X1.3 Planapo (oil). Both phase contrast. Images were resized and individually cropped to yield about the same apparent size of the diatom on the screen. Stacks, slightly tweaked (brightness and contrast, untouched color/hue).
In principle, best resolution is expected under green light; here, the purpose was just aesthetics.
Hope it was achieved.
viewtopic.php?f=10&t=9079
Further slide surfing revealed a Cyclotella meneghiniana Kutzing (tentative idn.). I was very happy since the Centrales are a rare find. So here are images, one with a 40X0.75 Neofluar (dry), the other with 100X1.3 Planapo (oil). Both phase contrast. Images were resized and individually cropped to yield about the same apparent size of the diatom on the screen. Stacks, slightly tweaked (brightness and contrast, untouched color/hue).
In principle, best resolution is expected under green light; here, the purpose was just aesthetics.
Hope it was achieved.
- Attachments
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- Cyclotella stack of 2 40X Neofluar.jpg (61.54 KiB) Viewed 6274 times
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- Cyclotella stack of 3 100X.jpg (74.59 KiB) Viewed 6274 times
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Re: More phase contrast photos of cleaned diatoms
These are amazing!
Re: More phase contrast photos of cleaned diatoms
Thanks DonSchaeffer.
Re: More phase contrast photos of cleaned diatoms
It certainly was achieved !
I’m a little puzzled by your ‘green light’ comment though ... would blue light not give better resolution?
MichaelG.
Too many 'projects'
Re: More phase contrast photos of cleaned diatoms
Thanks, Michael!
In theory, blue light is supposed to give better resolution due to the shorter wavelength, but I have read that in practice, the optical components of the phase contrast are optimized for green light (546nm); and also in practice, all common-use phase contrast scopes that I have met, like those used to inspect tissue cultures, are configured with a green filter. Once upon a time I recorded diatoms with green light and with blue light and to my eye, there was no difference...
Re: More phase contrast photos of cleaned diatoms
Thanks for the reply, Doron
I can think of three plausible reasons why Green might be considered optimum [as distinct from maximum]
One day [!] we should probably try some controlled experiments; but meanwhile, I respect your judgement.
MichaelG.
I can think of three plausible reasons why Green might be considered optimum [as distinct from maximum]
- The human eye is most sensitive in the Green region
- many monochrome cameras are also tuned to that range
- most colour cameras use the Bayer mosaic, which has twice the number of Green sub-pixels
One day [!] we should probably try some controlled experiments; but meanwhile, I respect your judgement.
MichaelG.
Too many 'projects'
Re: More phase contrast photos of cleaned diatoms
Willingly so. When I find a "standard", amphipleura pellucida (very rare here) or pleurosigma (supposedly common but missed it so far), and manage to mount them well.MichaelG. wrote: ↑Mon Apr 20, 2020 11:24 amThanks for the reply, Doron
I can think of three plausible reasons why Green might be considered optimum [as distinct from maximum]
- The human eye is most sensitive in the Green region
- many monochrome cameras are also tuned to that range
These are also good reasons for optimising the optics to suit.
- most colour cameras use the Bayer mosaic, which has twice the number of Green sub-pixels
One day [!] we should probably try some controlled experiments;
Last edited by Hobbyst46 on Mon Apr 20, 2020 1:02 pm, edited 1 time in total.
Re: More phase contrast photos of cleaned diatoms
Hi together,
a nice set of images again, Doron!
Green: I frequently divide the image apart ito th RGB channels when I only need a b/w image. I usually end up with the green channel. Blue is usually quite similar and also quite good, red is quite different in image ans usually a lot worse. But this is the result after photography with white LED-light. It might no be the same with tungsten light or with light that has already passed a colour filter.
Bob
a nice set of images again, Doron!
Green: I frequently divide the image apart ito th RGB channels when I only need a b/w image. I usually end up with the green channel. Blue is usually quite similar and also quite good, red is quite different in image ans usually a lot worse. But this is the result after photography with white LED-light. It might no be the same with tungsten light or with light that has already passed a colour filter.
Bob
Re: More phase contrast photos of cleaned diatoms
Hobbyst46, they are beautiful and stunning.
May i ask how do you clean your diatoms? (Sorry for an irrelevant question).
May i ask how do you clean your diatoms? (Sorry for an irrelevant question).
Daruosh.
Re: More phase contrast photos of cleaned diatoms
Thanks, Bob and darousha.
@darousha:
Diatoms were cleaned with APS - see this post:
viewtopic.php?f=10&t=8101&p=72044&hilit=APS#p72044
One step of boiling in APS, then, instead of repeating it, I rinsed with distilled water, then applied house-grade hypochlorite (clear liquid, not a gel or cream or mixture with anything else). For a couple of hours without warming. Then rinsed.
The whole process is not as efficient and comprehensive as some well-known laboratory procedures that rely on hazardous chemicals. On the other hand, it is much safer for the amateur.
Still, some knowledge and experience of handling materials are essential, and appropriate safety measures must be taken.
@darousha:
Diatoms were cleaned with APS - see this post:
viewtopic.php?f=10&t=8101&p=72044&hilit=APS#p72044
One step of boiling in APS, then, instead of repeating it, I rinsed with distilled water, then applied house-grade hypochlorite (clear liquid, not a gel or cream or mixture with anything else). For a couple of hours without warming. Then rinsed.
The whole process is not as efficient and comprehensive as some well-known laboratory procedures that rely on hazardous chemicals. On the other hand, it is much safer for the amateur.
Still, some knowledge and experience of handling materials are essential, and appropriate safety measures must be taken.
Re: More phase contrast photos of cleaned diatoms
Huge thanks for the explanation. I've watched a video on YouTube showing how to clean and mount the diatoms, but I cannot reproduce the results shown in the same video.Hobbyst46 wrote: ↑Mon Apr 20, 2020 3:58 pmThanks, Bob and darousha.
@darousha:
Diatoms were cleaned with APS - see this post:
viewtopic.php?f=10&t=8101&p=72044&hilit=APS#p72044
One step of boiling in APS, then, instead of repeating it, I rinsed with distilled water, then applied house-grade hypochlorite (clear liquid, not a gel or cream or mixture with anything else). For a couple of hours without warming. Then rinsed.
The whole process is not as efficient and comprehensive as some well-known laboratory procedures that rely on hazardous chemicals. On the other hand, it is much safer for the amateur.
Still, some knowledge and experience of handling materials are essential, and appropriate safety measures must be taken.
I'll try sodium hypochlorite. Thanks again.
Daruosh.
Re: More phase contrast photos of cleaned diatoms
@daruosha:
Here is an article about cleaning diatoms with hypochlorite:
A Simple, Inexpensive Method for Cleaning Diatoms
Author(s): Jennifer M. Carr, Gary L. Hergenrader, Nels H. Troelstrup and Jr.
Source: Transactions of the American Microscopical Society, Vol. 105, No. 2 (Apr., 1986),pp. 152-157
Published by: Wiley on behalf of American Microscopical Society
Here is an article about cleaning diatoms with hypochlorite:
A Simple, Inexpensive Method for Cleaning Diatoms
Author(s): Jennifer M. Carr, Gary L. Hergenrader, Nels H. Troelstrup and Jr.
Source: Transactions of the American Microscopical Society, Vol. 105, No. 2 (Apr., 1986),pp. 152-157
Published by: Wiley on behalf of American Microscopical Society
Re: More phase contrast photos of cleaned diatoms
Found the paper. Thanks a lot.Hobbyst46 wrote: ↑Mon Apr 20, 2020 6:18 pm@daruosha:
Here is an article about cleaning diatoms with hypochlorite:
A Simple, Inexpensive Method for Cleaning Diatoms
Author(s): Jennifer M. Carr, Gary L. Hergenrader, Nels H. Troelstrup and Jr.
Source: Transactions of the American Microscopical Society, Vol. 105, No. 2 (Apr., 1986),pp. 152-157
Published by: Wiley on behalf of American Microscopical Society
Daruosh.
Re: More phase contrast photos of cleaned diatoms
Hi Daruosh,
I have tried his method and was quite happy with the results. Here in Germany "bleach" is sold under the name "Clorix" and contains 2,6% sodiumhypochlorite.
This is a caustic substance and will destroy the diatoms if applied for too long.
Generally diatom cleaning consists of a range of methods and rarely just one step will be enough. Sand grains e.g. would practically unremovable chemically.
A while ago I presented diatom cleaning as a group topic: http://www.mikrohamburg.de/Programm/Pro ... 170917.pdf
Today I would present different methods: Heat, but only up to 450°C, sodium hypoclorite and Dorons APS method. From my perspective today these are the most promising methods for the home lab when effect, speed and safety are regarded. But the combination with physical methods as described in the (german) document in indispensable.
Here is an other simple method to clean diatoms:
1. Place mud with diatoms in a flat dish
2. cover with a fine net (e.g. 50 to 200µ hole size)
3. cover with water from where the mud is
4. place in a bright place for a day
5. Remove net with diatoms who have crept towards the light
Bob
Re: More phase contrast photos of cleaned diatoms
Really nice comparison. The second one looks stunning.
Btw what mounting media are you guys using?
Btw what mounting media are you guys using?
Zeiss Photomicroscope III BF/DF/Pol/Ph/DIC/FL/Jamin-Lebedeff
Youtube channel
Youtube channel
Re: More phase contrast photos of cleaned diatoms
Thanks Wes !
The mounting medium is Pleurax.
Some time ago I tried Norland's NOA 61, it is a lot easier to apply than Pleurax but less satisfactory because it does not always penetrate into the frustule. The mounted frustule then contains an ugly air bubble. Pleurax is better in this respect.
- KD Arvidsson
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- Joined: Wed Feb 12, 2020 6:47 pm
- Location: Sweden
Re: More phase contrast photos of cleaned diatoms
Very beatiful! Hobbyst46. Second picture is fantastic, sharp and very very nice! //KD
Microscope Nikon Labophot 2
Panasonic GH4 and HY-2307 Camera+Euromex adapter.
Westcoast of Sweden.
https://www.youtube.com/channel/UCjsgbq ... dyl2x0Atpw
Panasonic GH4 and HY-2307 Camera+Euromex adapter.
Westcoast of Sweden.
https://www.youtube.com/channel/UCjsgbq ... dyl2x0Atpw
Re: More phase contrast photos of cleaned diatoms
Thanks, KD Arvidsson.