My old black Cogit

What equipment do you use? Post pictures and descriptions of your microscope(s) here!
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Joel_U
Posts: 13
Joined: Wed Feb 10, 2021 2:25 pm

My old black Cogit

#1 Post by Joel_U » Wed Feb 10, 2021 4:22 pm

As a hobby brewer, I use an old Cogit microscope to check our yeast. Cogit was probably not a maker, they just stamped they name on basics microscopes.
This microscope is composed of a black stand, XY table. Abbe condenser and iris diaphragme, filter holder. Mirror two faces.
4 objectives 7X, 45X, 80X and 120 oil immersion. Eyepieces 5, 6, 10, 12 and a new WF 16.
Microscope01.jpg
Microscope01.jpg (118.68 KiB) Viewed 2989 times
As an improvement, I managed to get a led lightning between the legs of the stand.
20180807_195239.resized.jpg
20180807_195239.resized.jpg (47.74 KiB) Viewed 2989 times
Looking through the eyepiece was a little akward for "my old neck" so I added a tablet in afocal position. Now I can zoom on the tablet screen and share the view with my "Buddies Brewers".
Micro_Tablette_08_02_2019.jpg
Micro_Tablette_08_02_2019.jpg (71.14 KiB) Viewed 2989 times
I hope you can understand my poor gibberish. If it is ok some yeast pictures will come later.
Of course any comment or critiscisme are welcome.
Joël UGHETTO

MicroBob
Posts: 3154
Joined: Sun Dec 25, 2016 9:11 am
Location: Northern Germany

Re: My old black Cogit

#2 Post by MicroBob » Wed Feb 10, 2021 5:49 pm

Nice microscope setup, Joël!
These horse shoe microscopes are not often used today which is a pity as they perform very well, even for photography. Your setup for the tablet is very ingenious and a good idea to copy for people who can't look through eyepieces very well.

Bob

DonSchaeffer
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Joined: Sun Mar 22, 2020 10:06 am
Location: Winnipeg, Manitoba, Canada

Re: My old black Cogit

#3 Post by DonSchaeffer » Wed Feb 10, 2021 7:59 pm

Using the camera on the tablet by fitting a box under it is very ingenious.

hans
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Joined: Thu May 28, 2020 11:10 pm
Location: Southern California

Re: My old black Cogit

#4 Post by hans » Wed Feb 10, 2021 8:14 pm

Nice setup, what is the LED driver you are using? Looks similar to a handy little $7 square wave/PWM signal generator board I got recently but with built-in LED drive circuitry?

Joel_U
Posts: 13
Joined: Wed Feb 10, 2021 2:25 pm

Re: My old black Cogit

#5 Post by Joel_U » Wed Feb 10, 2021 9:08 pm

Thank you for your comments.
This microscope and all the stuff around is used to show "tiny things" to the Members of our Brewers Association. It has to be easy to move by car from my home to the Brewery, not take a long time to adjust and the ...experiments must be bulletproof. The Members have different levels of study and very often come with their Children. Each session involves 6 or 7 people hence the tablet : children in front and parents behind so that everyone can see the show !
During those sessions we look at a hair to show them that if you cannot see through ... the microscope is not that usefull, half of them prepare a slide with their own cheek cell with and without staining it, the other half a piece of onion skin epidermal stained by iodine. We prepare some yeast stained by methylen blue to play "Wanted dead or alive" and check wether our yeast is ok to ferment the next batch or not. As Brewers, we fear infections and they always want to see bacteria ... Not so easy, they have to collect with a toothpeek some "white stuff" at the foot of one of their own teeth and prepare the slide. Recording a video of the bacteria moving around always frighten them a little. "This is in MY mouth ??? NO .... impossible !!!".
With some red onions epidermis we look at the plasmolysis ( sometime reversible) by adding some brine (thank you Microbhunter microscopy). This experiment shows to our Brewers that throwing some yeast in a concentrated wort (Barley wine) could lead to some problems and stress the yeast.
End of the show, their eyes should shine... I am exhausted but happy.
I will post some photo.. But they are probably useless for you.

Hans, you are right it is a small PWM signal generator. The led radiator is a piece of copper tubing flattened and the light diffuser ... A piece of table tennis ball glued on the radiator.

MicroBob : In my case the bottleneck is not the microscope, it is the guy sitting in front of it :lol:
Joël UGHETTO

Want2see
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Joined: Mon Mar 01, 2021 6:40 pm

Re: My old black Cogit

#6 Post by Want2see » Wed Mar 03, 2021 10:44 pm

Really like the tablet setup

apochronaut
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Joined: Fri May 15, 2015 12:15 am

Re: My old black Cogit

#7 Post by apochronaut » Wed Mar 03, 2021 11:52 pm

Very good to see a beautiful old microscope still doing it's duty. Does it image genetically modified brewer's yeast as well as the generations old strains?
Cogit was a French brand of microscope but made in Germany for the French market. It probably was made by Seibert. The objective lens barrels on your microscope with the double flat knurled grip rings are identical to Seibert objectives I have seen. Might be Leitz that made the stand. Apparently , Seibert did a lot of contract work and for Leitz too.

Joel_U
Posts: 13
Joined: Wed Feb 10, 2021 2:25 pm

Re: My old black Cogit

#8 Post by Joel_U » Thu Mar 04, 2021 11:05 am

Want2see wrote:
Wed Mar 03, 2021 10:44 pm
Really like the tablet setup
It is really easy to setup a tablet on any monocular microscope. There is no physical contact between the microscope and the tablet, no vibration on the microscope when you zoom on the screen tablet. The tablet moves on the x,y plan only. On the z axis, I just pull the microscope tube up or down if I change the eyepiece. The screen is larger than the smartphones one.

Joel_U
Posts: 13
Joined: Wed Feb 10, 2021 2:25 pm

Re: My old black Cogit

#9 Post by Joel_U » Thu Mar 04, 2021 12:29 pm

apochronaut wrote:
Wed Mar 03, 2021 11:52 pm
Cogit was a French brand of microscope but made in Germany for the French market. It probably was made by Seibert. The objective lens barrels on your microscope with the double flat knurled grip rings are identical to Seibert objectives I have seen. Might be Leitz that made the stand. Apparently , Seibert did a lot of contract work and for Leitz too.
Thank you very much for those precisions. It looks like Cogit was retailer and depositary (not sure it is the right word) for Leitz in France :
http://www.lecompendium.com/dossier_opt ... _cogit.htm
The 4 objectives (20x, 45x, 80x, and 120x oil immersion) have the same shape and are parfocal.
Objectifs01.jpg
Objectifs01.jpg (130.47 KiB) Viewed 2598 times
Joël UGHETTO

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