Search found 1463 matches

by MichaelG.
Wed Oct 23, 2019 7:30 am
Forum: Beginner's corner
Topic: Am I doing something wrong?
Replies: 8
Views: 106

Re: Am I doing something wrong?

Just a side-note: There is an interesting report in today’s News https://news.sky.com/story/poor-toilet-hygiene-is-bigger-ecoli-risk-than-uncooked-food-research-11842110 ‘though, of course, the accompanying image of E.coli is not representative of what we can see with the light microscope. MichaelG.
by MichaelG.
Sat Oct 19, 2019 5:35 am
Forum: Microscopes and optics
Topic: Determining the molecular organisation of biological materials using polarized light microscopy
Replies: 6
Views: 114

Re: Determining the molecular organisation of biological materials using polarized light microscopy

tgss wrote:
Fri Oct 18, 2019 11:31 pm
Fascinating stuff Wes, excellent images and a very clear exposition of the physics of the process. Can you give an idea of the scale of the images, or at least the objective powers used?
Thanks for sharing.
Tom W.
+1 for that ^^^

MichaelG.
by MichaelG.
Fri Oct 18, 2019 8:47 am
Forum: Pictures and Videos
Topic: Salt, focus stacking
Replies: 8
Views: 218

Re: Salt, focus stacking

timurkhaz wrote:
Fri Oct 18, 2019 8:04 am
Due to the small field of view, i had to create panorama of 80 stacked pictures:)
With an astonishingly good result !!

Could you please describe your ‘workflow’

Thanks
MichaelG.
by MichaelG.
Wed Oct 16, 2019 10:09 am
Forum: Microscopes and optics
Topic: Field diaphragm problem
Replies: 21
Views: 597

Re: Field diaphragm problem

[…] These flat glass surfaces can really cause problems. My Pentax Q with 8,5mm standard lens that I use for years as my main microscope camera doesn't work well with the old Phomi 1, I get a red hot spot that I relate to the flat front surface of the objective. Somewhat disappointing that it shoul...
by MichaelG.
Tue Oct 15, 2019 9:06 am
Forum: Microscopes and optics
Topic: Mixed FN objectives on same head?
Replies: 7
Views: 125

Re: Mixed FN objectives on same head?

A quick look through some Olympus literature suggests that any differences must be in the head [observation tube in Olympus parlance] ... so, if the tube diameters are the same, perhaps the prisms are larger in the widefield heads. MichaelG. . See the list of Observation Tubes in this BX3, where the...
by MichaelG.
Tue Oct 15, 2019 8:02 am
Forum: Microscopes and optics
Topic: Mixed FN objectives on same head?
Replies: 7
Views: 125

Re: Mixed FN objectives on same head?

John,

Forgive my ignorance of the system, but ... is the body tube larger diameter on the ‘widefield’ instruments :?:

My suspicion is that you may get flare from internal reflections when using excessively large FN objectives.

MichaelG.
by MichaelG.
Sun Oct 13, 2019 11:36 pm
Forum: Home-made microscope adaptations
Topic: LEGO meets high-end microscopy
Replies: 2
Views: 115

LEGO meets high-end microscopy

I just found this fascinating paper, which includes a design for a rather neat specimen-holder [for relatively large specimens on a Light-Sheet-Microscope] that incorporates LEGO components.

https://www.frontiersin.org/articles/10 ... 26/full#F3

Be inspired !!

MichaelG.
by MichaelG.
Sun Oct 13, 2019 10:38 pm
Forum: Beginner's corner
Topic: Fusing glass slides
Replies: 23
Views: 840

Re: Fusing glass slides

[…] This is for the light sheet microscope. The proper containers are large cuvettes, Maybe about 55mm x 65mm and 25mm deep. They are made of some type of optical glass since the laser illumination has to pass through them. The imaging is through the open top of the container and doesn't pass throu...
by MichaelG.
Sun Oct 13, 2019 9:39 pm
Forum: Pictures and Videos
Topic: Salt, focus stacking
Replies: 8
Views: 218

Re: Salt, focus stacking

Very effective !!

Welcome to the forum.
MichaelG.
by MichaelG.
Sun Oct 13, 2019 9:05 am
Forum: Microscopes and optics
Topic: Early patents related to phase contrast
Replies: 7
Views: 588

Re: Early patents related to phase contrast

As some bloke from Stratford-upon-Avon wrote:

All’s well that ends well

MichaelG.
by MichaelG.
Sat Oct 12, 2019 7:08 am
Forum: Microscopes and optics
Topic: Early patents related to phase contrast
Replies: 7
Views: 588

Re: Early patents related to phase contrast

May I respectfully request a distillation of this thread in plain English for us Earth People? Thank you. 8-) Sorry, Kurt ... I don’t see the problem I would be happy to comply with your request if I knew what was wrong. Zernike was a man Patents are a claim of novelty of invention Phase Contrast i...
by MichaelG.
Fri Oct 11, 2019 7:59 pm
Forum: Microscopes and optics
Topic: Early patents related to phase contrast
Replies: 7
Views: 588

Re: Early patents related to phase contrast

Zernike patents on espacenet: https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=US&NR=2616334A&KC=A&FT=D&ND=3&date=19521104&DB=EPODOC&locale=en_EP Which cites https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=DE&NR=636168C&KC=C&FT=D&ND=3&date=19361007&DB=EPO...
by MichaelG.
Fri Oct 11, 2019 7:57 am
Forum: Microscopes and optics
Topic: Opening Zeiss 47 30 28 Trinocular Head
Replies: 11
Views: 633

Re: Opening Zeiss 47 30 28 Trinocular Head

75RR wrote:
Thu Oct 10, 2019 7:21 pm
Happy to say it worked
Thanks for the confirmation: In future years, people will be comforted by your success !!

MichaelG.
by MichaelG.
Thu Oct 10, 2019 5:38 pm
Forum: Microscopes and optics
Topic: Opening Zeiss 47 30 28 Trinocular Head
Replies: 11
Views: 633

Re: Opening Zeiss 47 30 28 Trinocular Head

I don't know for sure, but it certainly looks like those dimples are 'location catches'
... if it was mine, I would just pull gently

MichaelG.
by MichaelG.
Tue Oct 08, 2019 5:01 pm
Forum: Home-made microscope adaptations
Topic: Home made (Very Basic) Microtome
Replies: 42
Views: 2941

Re: Home made (Very Basic) Microtome

mrsonchus wrote:
Tue Oct 08, 2019 12:34 pm
I have to take the dog to the vet' soon..... bad teeth and partial deafness, the dog that is, not me! :D
So can we safely assume that the vet is healthy ?
;)

MchaelG.
by MichaelG.
Mon Oct 07, 2019 9:22 pm
Forum: Home-made microscope adaptations
Topic: Home made (Very Basic) Microtome
Replies: 42
Views: 2941

Re: Home made (Very Basic) Microtome

Thanks, Bob
I’ve not seen that style before.
... Every day is a learning day !!

MichaelG.
by MichaelG.
Mon Oct 07, 2019 6:35 pm
Forum: Home-made microscope adaptations
Topic: Home made (Very Basic) Microtome
Replies: 42
Views: 2941

Re: Home made (Very Basic) Microtome

Hi Michael, in my experience hand microtoms with object clamp and a big opening in the table are more useful. The shown has only a tiny hole in the table so you might be able to lead a stem through it, but not to support it on it's way. Here in Germany hand microtomes are very popular, but they onl...
by MichaelG.
Mon Oct 07, 2019 3:42 pm
Forum: Home-made microscope adaptations
Topic: Home made (Very Basic) Microtome
Replies: 42
Views: 2941

Re: Home made (Very Basic) Microtome

Roldorf,

Now that you have proved you can make your own ...
You may be interested in this; which is currently on special offer
https://www.surplusshed.com/pages/item/M1571D.html

Seems a fair price, and Fred is an honourable chap when it comes to postal charges.

MichaelG.
by MichaelG.
Sun Oct 06, 2019 6:29 pm
Forum: Camera systems and imaging
Topic: MC 63 Zeiss
Replies: 7
Views: 1191

Re: MC 63 Zeiss

William,

It's of no relevance, given that we can pick them up for free these days [!] ... but you may be interested to see the list price of your controller:
http://earth2geologists.net/Microscopes ... g_1978.pdf

Page 5.19

MichaelG.
by MichaelG.
Sat Oct 05, 2019 4:31 am
Forum: Beginner's corner
Topic: minimizing harm
Replies: 61
Views: 7509

Re: minimizing harm

mnmyco wrote:
Sat Oct 05, 2019 12:30 am
Sorry if this is a repeat, but you can block most or all UV with just some clear plastic filters. Lexan will basically block all UV light, though IR will be transmitted.
Useful links, thanks
... Although it is, of course, the IR which has the heating effect to evaporate the water.

MichaelG.
by MichaelG.
Fri Oct 04, 2019 6:32 am
Forum: Camera systems and imaging
Topic: CMY or RGB ... a mystery
Replies: 16
Views: 541

Re: CMY or RGB ... a mystery

Lets see what the NEXT problem will be! Unless you were thinking of world politics, Bob [in which case, all bets are off] ... I think this might be it : Slo-mo is the real stand-out here, at least on the page – 960fps has become the high-end mobile standard for slo-mo video, but the Mate 30 Pro goe...
by MichaelG.
Fri Oct 04, 2019 5:51 am
Forum: Microscopes and optics
Topic: A DIY Wild M400 / M420 Macroscope
Replies: 1
Views: 179

Re: A DIY Wild M400 / M420 Macroscope

.
That all seems to have worked-out very nicely !!

Thanks for sharing the detail of various components.

MichaelG.
by MichaelG.
Thu Oct 03, 2019 8:11 pm
Forum: Microscopes and optics
Topic: Zeiss afocal photo adapter45 60 29 ... and variations on the theme?
Replies: 32
Views: 1761

Re: Zeiss afocal photo adapter45 60 29 ... and variations on the theme?

Hi Michael, frequently the Pentax M 40mm 1:2,8 is used. Real wide angles for SLRs are usually retrofocus designs but some 1:3,5 version are built quite short. They might fit to an eyepiece with lots of eye relief. A 35mm objective buchered from a Minox 35mm camera would probably work very well but ...
by MichaelG.
Thu Oct 03, 2019 7:53 pm
Forum: Microscopes and optics
Topic: Zeiss afocal photo adapter45 60 29 ... and variations on the theme?
Replies: 32
Views: 1761

Re: Zeiss afocal photo adapter45 60 29 ... and variations on the theme?

I think that even under this afocal setting, the flatness of field and chromatic correction of the MFP4:1 are fairly similar to those of the KPL 8X. The FOV of the MFP4:1 is narrower, but it is still usable. That seems a somewhat surprising result, Doron, but I agree ... the images speak for themse...
by MichaelG.
Thu Oct 03, 2019 7:11 pm
Forum: Microscopes and optics
Topic: Zeiss afocal photo adapter45 60 29 ... and variations on the theme?
Replies: 32
Views: 1761

Re: Zeiss afocal photo adapter45 60 29 ... and variations on the theme?

Thanks, Bob ... That's probably saved me wasting precious time [and a little money] experimenting.

MichaelG.
by MichaelG.
Wed Oct 02, 2019 10:09 pm
Forum: Camera systems and imaging
Topic: CMY or RGB ... a mystery
Replies: 16
Views: 541

Re: CMY or RGB ... a mystery

I may have deduced the answer to my opening question ! ...Could someone please review my thinking ? Let’s assume that there is actually a black dot on a white background ... a reasonable approximation of what should be seen in my ‘tiny crop’ We know that the Achromat will suffer Chromatic Difference...
by MichaelG.
Wed Oct 02, 2019 8:35 am
Forum: Camera systems and imaging
Topic: CMY or RGB ... a mystery
Replies: 16
Views: 541

Re: CMY or RGB ... a mystery

This is a very present problem: Photographs are increasingly the result of simple image capture and digital "improvement". Increasing or reducing depth of field, sharp free hand pictures in very dim light, resoultion and colour that is based on artificial intelligence, lens abberation correction......
by MichaelG.
Wed Oct 02, 2019 8:31 am
Forum: Microscopy accessories
Topic: Eyepiece micrometer diameter?
Replies: 4
Views: 414

Re: Eyepiece micrometer diameter?

Petro,

I recently found this very useful list:
https://laboratoryresource.com/?navaction=getitem&id=22

MichaelG.
by MichaelG.
Wed Oct 02, 2019 8:22 am
Forum: Beginner's corner
Topic: 6.3x and 63x Why?
Replies: 5
Views: 367

Re: 6.3x and 63x Why?

The underlying mathematics of the relevant ‘series’ is well described in this Wikipedia page about f-stops https://en.m.wikipedia.org/wiki/F-number ... look at the one-third-stop series, and you will find 6.3 Admittedly the context is different, but similar logic applies to specifying increments of...