Scope Status

What is your microscopy history? What are your interests? What equipment do you use?
Post Reply
Message
Author
User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Scope Status

#1 Post by linuxusr » Thu Apr 22, 2021 3:54 pm

Hello All:

Perhaps 25 years ago I purchased a Nikon AlphaPhot2 at UCLA, my first microscope. Mostly I observed Protista and took a particular interest in the biology of Stentor but found little information--that was before the digital revolution. With hay infusions as a starter, I regularly dipped into protista/bacterial colonies to view the common specimens you are all familiar with, the Rotifers, for example.

I am definitely a beginner. For some years, I have been planning for my second microscope and decided that the one specification I wanted was Koehler illumination. I purchased the Zeiss Primostar 3, full Koehler, with a Pelican case. It has taken me about a week and 50 or so fixed slides to learn Koehler illumination and I think I have achieved executing it. First, the optics are much more complicated than the steps. Second, although there is a wealth of tutorials available online, there are subtleties in the process whereby you recognize that the tutorials only bring you so far. Like math, you need to practice to get some of the finer permutations.

I am a retired English teacher, 30 years, Los Angeles, CA, and in 2008 I retired permanently to the Dominican Republic/Haiti. I am briefly in the U.S. for my COVID vaccination. I had a lot of trepidation about returning to the D.R. with my expensive instrument (~$3,000.00 with case), so I have purchased a separate airfare for my Zeiss to sit next to me with seatbelt extenders, two boarding passes, etc.
Can you blame me? LOL!

My first question is going to be about immersion oil solvents but I'll post that in the appropriate sub-forum. Again, greetings to all.
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#2 Post by linuxusr » Thu Apr 22, 2021 3:58 pm

OP PS:

I am a senior citizen and sometimes my memory slips! I didn't even know that I was already a member of this forum but I got a clue when I found out that my user name AND email address were already taken. So maybe this is my second introduction. Ha! Ha! (We didn't have "LOL" back in the day).
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

dtsh
Posts: 977
Joined: Wed May 01, 2019 6:06 pm
Location: Wisconsin

Re: Scope Status

#3 Post by dtsh » Thu Apr 22, 2021 4:36 pm

It seems to me that a lot of the explanations of Koehler make it more complex than it needs to be and get lost in the details rather than providing clear examples of what do to and how to know you've done it.
I allow it's entirely possible that I'm doing it wrong, but I put a specimen on the stage, focus on it, close the field iris until I can see the edges of the leaves, adjust the height of the condenser until the iris is resolved clearly, then open the iris back up until it's just out of the field.

Koehler isn't required, it allows for better imaging but peole have taken good images with instruments entirely incapable of Koehler.

Oh, and greetings from another long-time linux user, been my primary platform since the mid 90's

BramHuntingNematodes
Posts: 1538
Joined: Tue Jan 21, 2020 1:29 am
Location: Georgia, USA

Re: Scope Status

#4 Post by BramHuntingNematodes » Fri Apr 23, 2021 1:27 am

I hope you will post some pictures. I would be interested in seeing the biodiversity of DR
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#5 Post by linuxusr » Fri Apr 23, 2021 4:51 am

@BramHuntingNematodes
I will have had a lot of microscopy sessions before I even think of photography! Hopefully, I'll still be alive when that time comes and can upload some photos. One of my first tasks will be knife scrapings of lichens I see on many 500 year old buildings, then hydrating and hoping for tardigrades, well, they seem to be ubiquitious world-wide: the extremophiles of the Protista. Their genetics seem to be highly conserved, so I don't think I'll have anything special to turn up there.

Hell, the Zeiss C-Mount alone is just shy of $400.00. With the spec for the threading, though, I'm sure I can find a third-party mount . . .

@dtsh
Well you beat me on longevity for Linux as primary OS. It's been my primary OS since Ubuntu Dapper Drake and now Canonical is on round two of the alphabet with Hirsute Hippopotamus in beta . . . I used RHEL briefly before that.

Yes, Koehler illumination does not increase resolution but it does remove light artifacts and provide a uniform field of view. Your steps match mine. I found it striking that my condenser lens resolves the field illumination image around a mere 3mm below the bottom of the slide. I also note that the field aperture image is a polygon, a duodecagon, and it's the lines making up the perimeter that you focus. Once you center at 4x, you really don't need to center again. And, more or less, just as objectives have parfocality, so when you sharply resolve the field image, it pretty much sticks, say from 10x to 40x. But I always check anyway because sometime it can use a little adjustment.

Also, when I focus my specimen, before I even close the field diaphragm or focus my condenser, I automatically adjust the lever of the condenser aperture to match the objective. I can't see the point of looking through the ocular tube. When I first tried to get Koehler, I was disappointed with my scope and thought that I wasted my money but now that I am getting greater precision I am very happy with it. As an aside, I almost got sucked into buying a scope that was not full Koehler. It was described as "simple" Koehler (no adjustable field diaphragm); even Zeiss' scope that is not full Koehler is described as "fixed" Koehler. To me, it's either Koehler or it's not. The technical requirements for K. illum. are two adjustable apertures, not one. What instrument are you using?
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

apochronaut
Posts: 6272
Joined: Fri May 15, 2015 12:15 am

Re: Scope Status

#6 Post by apochronaut » Fri Apr 23, 2021 11:40 am

The marketing of average grade Chinese microscopes utilizes a lot of tropes such as abbe, köhler, full köhler, diopter, interpupillary, parfocal, anti-reflection coatings, oil immersion, D.I.N. W.F., to sell microscopes to noobs. It's like saying a car has inflatable tires, hinge mounted doors,rollup windows,a full length exhaust pipe, electric starter etc. etc.

Any microscope made in the past 60 years above a student grade should be expected to have most or all of those standard features that are trumpeted so loudly in marketing literature. Many microscopes exist with enhanced features above those basics that go over the heads of noobs too, so in the long run it does seem that the purveyors of that broad expanse of Chinese hardware do know who they are selling to.

Now let me get this straight. You retired to a tropical island , are returning by jet to the U.S. to escape the terror of the outbreak there in order to get vaccinated and are returning via jet with an extra seat purchased for your new $3000.00 microscope?
Any chance you could have tossed a few extra doses of vaccine in the pockets of your Greg Lauren cargo shorts?

dtsh
Posts: 977
Joined: Wed May 01, 2019 6:06 pm
Location: Wisconsin

Re: Scope Status

#7 Post by dtsh » Fri Apr 23, 2021 12:55 pm

linuxusr wrote:
Fri Apr 23, 2021 4:51 am
@dtsh
Well you beat me on longevity for Linux as primary OS. It's been my primary OS since Ubuntu Dapper Drake and now Canonical is on round two of the alphabet with Hirsute Hippopotamus in beta . . . I used RHEL briefly before that.

Yes, Koehler illumination does not increase resolution but it does remove light artifacts and provide a uniform field of view. Your steps match mine. I found it striking that my condenser lens resolves the field illumination image around a mere 3mm below the bottom of the slide. I also note that the field aperture image is a polygon, a duodecagon, and it's the lines making up the perimeter that you focus. Once you center at 4x, you really don't need to center again. And, more or less, just as objectives have parfocality, so when you sharply resolve the field image, it pretty much sticks, say from 10x to 40x. But I always check anyway because sometime it can use a little adjustment.

Also, when I focus my specimen, before I even close the field diaphragm or focus my condenser, I automatically adjust the lever of the condenser aperture to match the objective. I can't see the point of looking through the ocular tube. When I first tried to get Koehler, I was disappointed with my scope and thought that I wasted my money but now that I am getting greater precision I am very happy with it. As an aside, I almost got sucked into buying a scope that was not full Koehler. It was described as "simple" Koehler (no adjustable field diaphragm); even Zeiss' scope that is not full Koehler is described as "fixed" Koehler. To me, it's either Koehler or it's not. The technical requirements for K. illum. are two adjustable apertures, not one. What instrument are you using?
I adopted Linux early, partly due to poverty. I've done well with it, managed to leverage it for a career that's been rewarding. It's changed a lot over the years, largely for the better I think.

My scopes are a Leica 410 with phase contrast and a couple of AO10 stands setup for brightfield and darkfield, nothing fantastic but good performers. I've been fooling around with microscopes off and on for years, but didn't approach it seriously until the last couple of years. Lots to learn and I'm having fun, which is what counts. You?

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#8 Post by linuxusr » Sat Apr 24, 2021 3:25 am

@dtsh

Yes, the great thing about amateur microscopy is that you are free to explore. Although I'm exploring to have fun and intellectual stimulation, I do seek best practices, as you'll see when I start posting in some of the sub-forums.

I have a darkfield slider but I'm not even going to use that yet until I hone and find best practices for straightforward brightfield microscopy. As an example, my 100x is underused because of hesitations. An example is that if I'm going to clean my slides, I must avoid oil on a slide from contaminating my lower power. So for my used slide jars, I think I'll lable one "oil." When I clean, I'll find some solvent, maybe 1 part liquid detergent to 99 parts water, and bathe those slides separately . . . There's a bunch of procedures and techniques I need to hone. Meanwhile, I'll start exploring in parallel: a. lichens hydrating for tardigrades, b. hay infusion for protist/bacterial colony, c. found objects in the environment.

For Linux, I have a folder titled OS Install which I keep in a Dropbox folder. In there I have a copy/paste of my CLI history; screenshots of my Opera browser tiles; the latest .iso, etc. Whenever I need to do a clean install, I get up and running with config. in about two hours. I always use a LTS.

@apochronaut

For sure, there are all manner of inexpensive scopes that work fine for amateurs. Some items you mention, however, are not "extras," such as parfocality and binocular interpupillary distance.

Yeah, that's right, I came to the U.S. only for a vaccination and I'm returning with a $3,000 scope and case in a separately purchased seat. Strange things happen when you are retired and the world is your oyster. In general, if you don't hurt yourself and you don't hurt others, you can do what you want!

I don't wear shorts. I'm not a tourist.
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Scope Status

#9 Post by 75RR » Sat Apr 24, 2021 1:18 pm

linuxusr wrote:
Thu Apr 22, 2021 3:54 pm
I had a lot of trepidation about returning to the D.R. with my expensive instrument (~$3,000.00 with case),
so I have purchased a separate airfare for my Zeiss to sit next to me with seatbelt extenders, two boarding passes, etc.
Can you blame me? LOL!
Not me, I have seen first hand how baggage handlers at airports treat luggage.

My microscope survived only because I had dismantled it completely (think flat-pack) and then packed each part individually.

A couple of links you might find useful:

http://zeiss-campus.magnet.fsu.edu/mobi ... obile.html

https://www.zeiss.com/content/dam/Micro ... -zeiss.pdf

And an image showing several illumination techniques on the same Closterium, since Brightfield is basically just a starting point.

Brightfield, Oblique, Darkfield and Phase

ImageImage Image Image
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#10 Post by linuxusr » Sun Apr 25, 2021 12:21 am

@75RR

Those images are beautiful aesthetically and morphologically.

I still have to check those site URL's but I am aware of them. Here are some more:

tardigrade.us
nikonsmallworld.com
olympusbioscapes.com
microscopy-uk.org.uk
sciplus.com
leefilters.com
rheinberg-filters.com

I have not vetted all of these, so YMMV.

If my Zeiss cannot board the plane, I will not board the plane. Even if baggage is not thrown, when it descends from the baggage carousel, it slams against the retaining wall. My Pelican case cost $270.00. I made some mistakes fitting the scope to the foam, so now I'm buying a special spray to customize some of the foam parts. I find it's better to set the scope on the foam base, then to insert the foam cutouts and work them in. And the oculars have to be pulled and the head rotated . . .

Did you remove the head?
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#11 Post by linuxusr » Sun Apr 25, 2021 12:24 am

OP#2

I agree. Brightfield is the starting point. I have a darkfield slider but I'm not going to bother with it.
I will first hone my brightfield techniques. Then learn more about other illumination techniques later. Otherwise, you spread yourelf too thin: "Jack of all trades, master of none."
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Scope Status

#12 Post by 75RR » Sun Apr 25, 2021 7:38 am

linuxusr wrote:
Sun Apr 25, 2021 12:24 am
I will first hone my brightfield techniques. Then learn more about other illumination techniques later. Otherwise, you spread yourelf too thin: "Jack of all trades, master of none."
'Practice makes perfect' certainly applies to Microscopy.

Did take the head off, and everything else as well (an advantage of the Zeiss WL).

Did not have a dedicated case though. A Pelican case is a good idea. What model did you get?

My links above are to an Interactive Köhler tutorial and to a booklet on cleaning a microscope, which should answer most of your questions.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#13 Post by linuxusr » Sun Apr 25, 2021 8:20 pm

Model 1560 pelican.com

It was recommended to me by tech support at microscopeworld.com where I bought my scope. They had fitted it into the Primostar 3 (new model). There's a problem with the angled base of the body. It only fits when the foam above and below is completely compressed. I had to use about five pounds of force to close the lid. However, the contact point is the body and the body is very sturdy. I made separate compartments for the eyepieces and rotated the head 180 degrees.

Make sure you take the exterior dimensions of your scope and the interior dimensions of the case (published with specs) before you buy. The system comes with a base foam layer a top egg crate layer and two foam inserts which have 100's of about 0.25 x 0.25 pluckable foam pieces. As hard as I tried to get it right, I still make mistakes, more aesthetic than functional. I ordered a 3M adhesive spray so I can futher customize and get it more professional looking. When I finished my cutouts, the scope was difficut to fit in, partly because I could not hold the moveable head. Better way: Remove the cutouts and position the scope on the base. Work in each insert around the permeter manually.

The case has many features which you can read about, including holes for two padlocks.

As you know, it was Zeiss technicians who invented both Koehler illumination and the Abbe condenser.
Thanks for the K. illumination tutorial. After working on K. illumination for a week, I think I am doing it well. But I'm sure I'll learn more when I go through the tutorial. The downloadable cleaning book is also excellent.
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

apochronaut
Posts: 6272
Joined: Fri May 15, 2015 12:15 am

Re: Scope Status

#14 Post by apochronaut » Sun Apr 25, 2021 11:12 pm

Actusaly, Zeiss were condenser denyers. Ross had already invented the achromat condenser by 1849. Abbe merely offered Zeiss the cheapest design that would get them a functional condenser, since they had none and hadn't figured out it's importance . When the abbe was invented it turned out to be a good basic tool for basic microscopes( in todays world that means probably under about 1000.00) . Any decent microscope above that price threshold should probably be fitted with a condenser a little higher on the food chain. An abbe condenser is about like eating soup with a slotted spoon instead of a spoon, compared to a real condenser.

As far as the Köhler illumination system is concerned, it was a response to a bad turn of events in microscope illumination.The coiled filament required a solution to it's existence and Köhler designed a solution and presented it to Zeiss. Similar solutions existed elsewher due to necessity but they just didn't get wanked over so much. Kòhler illumination is kind of like a McDonalds hamburger. It is an acceptable way of solving a problem caused by a mismatch of technologies.

Zeiss has been legally priveledged and very hawkish in securing patents over the years so a lot has become associated with them that did not originate with them. There is no doubt that Zernicke went to them with phase because he was a Dutch jew and that solved a big problem. History has not looked favourably on Zeiss regarding their actions during W.W. Ii but they have gotten away with it. . Zernicke; well he had something to offer and patent. Saved his neck for sure. And what Zeiss had to offer the Russians and the Americans in 1946 ; well that probably saved a few necks.
On the other hand: Leitz were the opposite.

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Scope Status

#15 Post by 75RR » Mon Apr 26, 2021 6:10 am

.
What is known as Köhler is not just a solution to an intrusive coil filament as apochronaut would like everyone to believe.

While a solution to the intrusive coil filament was what launched Köhler’s study into lenses – his investigations led to a firm scientific understanding

of how lenses interact and the importance of their correct positioning in relation to each other.

When you set up Köhler you are correctly and precisely aligning your microscope, this not only gives improved illumination but also maximizes the resolution of the objective.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

apochronaut
Posts: 6272
Joined: Fri May 15, 2015 12:15 am

Re: Scope Status

#16 Post by apochronaut » Mon Apr 26, 2021 10:32 am

That is true and makes it easier for a company to engineer and produce simple illumination systems on fairly simple microscopes but the importance of Köhler illumination is way overstated. It is useful where you need it because it has been engineered into the system and unnecessary where you do not. It has however become a banal buzzword, utilized as a marketing tool to sell overpriced student microscopes to unsuspecting neophytes because they think they are getting something special.

Sabatini
Posts: 464
Joined: Tue Nov 12, 2019 3:09 am

Re: Scope Status

#17 Post by Sabatini » Tue Apr 27, 2021 12:54 am

This is getting pretty interesting!!
Thanks you .

User avatar
linuxusr
Posts: 220
Joined: Sun Jun 24, 2018 9:00 pm
Location: Dominican Republic

Re: Scope Status

#18 Post by linuxusr » Wed Apr 28, 2021 2:56 am

Assuming all parameters are equivalent, a starting point would be to compare non-Koehler, fixed-Koehler, and full-Koehler, same manufacturer and objectives and fixed specimen and photographs under the same conditions, and do the comparison blindly.

Meanwhile, the Koehler microscopists have bragging rights and probably more fun manipulating their images! More parameters to adjust = > inputs.

The politics and history of optical microscope manufactures is beyond this beginning amateur contemplating drymount techniques, if drymount manipulation can even be called a technique, but I'm glad to see a range of experience and love for the hobby/science at this site.

Probably much less to debate among EM manufacturers . . .
Nikon AlphaPhot 2 < Zeiss Primostar 3, Full Köhler; Axiocam 208 Color < UHD LG
Aller Anfang ist schwer.

Post Reply