There is DIC, then there is DIC

Everything relating to microscopy hardware: Objectives, eyepieces, lamps and more.
Post Reply
Message
Author
thomas.schwarz
Posts: 121
Joined: Tue Aug 27, 2019 5:04 pm

There is DIC, then there is DIC

#1 Post by thomas.schwarz » Fri Nov 15, 2019 10:04 pm

Hello friends,

Are there better and worse DIC? If yes what does it depend on? Is the DIC in a Nikon e400 good?

Thanks
Tom

PeteM
Posts: 978
Joined: Tue Dec 06, 2016 6:22 am
Location: N. California

Re: There is DIC, then there is DIC

#2 Post by PeteM » Fri Nov 15, 2019 11:01 pm

Tom, The E400 is a fine microscope, but I don't believe it has the turret openings for a polarizer and DIC slider. At least that's my limited experience. The E600 does offer that.

There may well be a workaround from Nikon, such as an intermediate piece to hold the prisms/analyzer? You might also be able to adapt something.

I've had some success in adapting intermediate tubes to hold prisms and polarizers above the objective. And then modifying condensers to hold various prisms and a polarizer below the condenser iris.

If things are just right, the background seems a sort of translucent gray. I assume this is "proper" DIC, but am only a year or so into this with no formal experience. In other cases, the background is more of a matt gray, but with various features of the specimen showing relief that changes with adjustments to the prism and (to a limited extent) the polarizers. While the images are good to the eye, I assume the prisms are slightly mismatched?

In still other cases, it's easy to convince yourself that a combination of oblique lighting and color shifts from the prisms are DIC -- but it's most likely just oblique and the equivalent of adding a quarter/half/full wave plate. Least those are my guesstimates. Cool photographic effects, but not well matched prisms and sometimes way too much or little shift in home brew systems.

DIC is very cool, but even a properly matched system isn't a silver bullet to turn every so-so brightfield image into stunning relief. Specimens like to be thin and somewhat transparent (cells!) to show DIC at its best.

As for your question, I'm curious too about the relative merits of various systems.

MicroBob
Posts: 1990
Joined: Sun Dec 25, 2016 9:11 am
Location: Northern Germany

Re: There is DIC, then there is DIC

#3 Post by MicroBob » Sat Nov 16, 2019 8:01 am

Hi Tom,
since DIC sets are rare only few amateurs can really compare them well. When you have typical amateur know-how and funds you probably can be happy with any complete and working set you find within your budget. The old Zeiss DIC (pre 1975) was limiting the condenser aperture somewhat, but was very flexible in the choice of objectives. The newer Zeiss DIC was slightly better suited to finest structures but had a tendency towars prism delamination. PZO DIC is somewhat limited by the simple condenser an uncoated optics. All other systems are even rarer (at least here in Germany). It is not uncommon to take several years of hunting to complete a DIC set - not ideal for everyone!

Bob

User avatar
75RR
Posts: 6814
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: There is DIC, then there is DIC

#4 Post by 75RR » Sat Nov 16, 2019 11:21 am

PeteM wrote:
Fri Nov 15, 2019 11:01 pm

DIC is very cool, but even a properly matched system isn't a silver bullet to turn every so-so brightfield image into stunning relief. Specimens like to be thin and somewhat transparent (cells!) to show DIC at its best.
To this I can only add that you are seeing the best of them. Not every session produces an image one would want to share!

MicroBob wrote:
Sat Nov 16, 2019 8:01 am
Hi Tom,
since DIC sets are rare only few amateurs can really compare them well. When you have typical amateur know-how and funds you probably can be happy with any complete and working set you find within your budget. The old Zeiss DIC (pre 1975) was limiting the condenser aperture somewhat, but was very flexible in the choice of objectives. The newer Zeiss DIC was slightly better suited to finest structures but had a tendency towars prism delamination. PZO DIC is somewhat limited by the simple condenser an uncoated optics. All other systems are even rarer (at least here in Germany). It is not uncommon to take several years of hunting to complete a DIC set - not ideal for everyone!

Bob
Add a bit of luck to the mix and that is the reality for most of us.

If however you happen to have more funds available than the average hobbyist has or can get away with spending, then things look up a bit.

Complete used DIC microscopes can be had at around 3000 usd and up viewtopic.php?f=16&t=7611&p=67234&hilit ... ope#p67234

I would suggest looking at DIC images that you like both here and in https://www.photomacrography.net/forum/ ... 2e28a3d3af and asking what they used.

If your budget is in the 10k -15k range then I think you can look at new. Certainly worth your while getting some quotes.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

thomas.schwarz
Posts: 121
Joined: Tue Aug 27, 2019 5:04 pm

Re: There is DIC, then there is DIC

#5 Post by thomas.schwarz » Mon Nov 18, 2019 9:07 pm

PeteM wrote:
Fri Nov 15, 2019 11:01 pm
Tom, The E400 is a fine microscope, but I don't believe it has the turret openings for a polarizer and DIC slider.
I am a total novice, but I think I have (always) seen the slot that you are referring to. So far I think the answer is a resounding "yes" and "no" )))). Like the universe.

With that said, regarding the Nikon 400e, for sale recently on this website, there is written re objectives:

100x Plan Flour DIC/BF objective

So ...dic? Means what? Flour means florescent? And bf means before you buy figure out what this is?

))))

User avatar
75RR
Posts: 6814
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: There is DIC, then there is DIC

#6 Post by 75RR » Mon Nov 18, 2019 9:12 pm

This should give you an idea of the components needed for DIC

https://www.microscopyu.com/pdfs/Lassle ... 9-2006.pdf
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

Hobbyst46
Posts: 2592
Joined: Mon Aug 21, 2017 9:02 pm

Re: There is DIC, then there is DIC

#7 Post by Hobbyst46 » Mon Nov 18, 2019 9:28 pm

thomas.schwarz wrote:
Mon Nov 18, 2019 9:07 pm
100x Plan Flour DIC/BF objective
So ...dic? Means what? Flour means florescent? And bf means before you buy figure out what this is?
Flour (I guess the spelling was actually Fluor) does not mean fluorescence. It is an abbreviation for fluorite glass objective, which provides partial correction of color aberration, better than achromat though less than apochromat.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

PeteM
Posts: 978
Joined: Tue Dec 06, 2016 6:22 am
Location: N. California

Re: There is DIC, then there is DIC

#8 Post by PeteM » Mon Nov 18, 2019 10:14 pm

When an objective is marked "DIC" it's much like being marked "POL" (e.g suitable for polarization). It usually just indicates that the objective is optically clear enough not to be troubled by having prisms and polarizers in line - not that it produces a DIC image on its own. With better objectives (e.g. Olympus SPlan and likely many of the Nikon Plan Fluors) even those not marked "DIC" are likely good enough to be used once you have all the proper prisms and polarizer and analyzer in place and properly adjusted.

thomas.schwarz
Posts: 121
Joined: Tue Aug 27, 2019 5:04 pm

Re: There is DIC, then there is DIC

#9 Post by thomas.schwarz » Sun Nov 24, 2019 9:17 am

PeteM wrote:
Mon Nov 18, 2019 10:14 pm
When an objective is marked "DIC" it's much like being marked "POL" (e.g suitable for polarization). It usually just indicates that the objective is optically clear enough not to be troubled by having prisms and polarizers in line - not that it produces a DIC image on its own. With better objectives (e.g. Olympus SPlan and likely many of the Nikon Plan Fluors) even those not marked "DIC" are likely good enough to be used once you have all the proper prisms and polarizer and analyzer in place and properly adjusted.

Thanks clear. Then more specifically, I see some DIC systems have the Nomarski Prism. I are there better and worse Nomarski prisms?

Tom Jones
Posts: 139
Joined: Wed Apr 13, 2016 3:47 pm

Re: There is DIC, then there is DIC

#10 Post by Tom Jones » Sun Nov 24, 2019 4:15 pm

ALL transmitted light DIC requires polarized light and two Nomarski prisms. Reflected light DIC requires only one as the light passes through it twice. All of the prisms are expensive and limited as to the number of objectives they will work with, often being designed to work with one specific objective. Trying to mix components from one manufacturer or microscope system with another is risky. It might work fine, and it might not work at all, so it's a bit of a crap shoot.

I absolutely love DIC and have it on several microscopes. BUT, before you spend a lot of your treasure, learn what your microscope is capable of without it. Less expensive techniques such as darkfield, phase contrast, and particularly oblique lighting are often better suited for a given specimen. Darkfield and oblique can be almost free, and phase is cheap compared to DIC.

You can easily end up with more money in DIC components than your entire microscope is worth without them, and only the research-oriented microscopes are equipped to accept the DIC systems. The intermediate tube and upper prism slider for my BHS cost a little more than $1,000. The BH2-UCD universal condenser cost me $1,000 without any of the interchangeable prisms, although you can sometimes get one with fixed prisms for less, and I just picked up a really rare set of four objective prisms for DPlanApo objectives and the UCD that came in at $1,800. That's $3,800 without the microscope or objectives! A U-UCD8-2 universal condenser for my Olympus BX-50, with a dry top lens and tint plate, but no prisms, just cost me $3,965 from Olympus. :o They're really rare on eBay and I got tired of waiting. A couple of rare, new, high contrast prisms were $675 each. Most prisms on eBay are at least $300+. Cheap this ain't.

Don't just jump into this. If you are contemplating going down this road, you should do a lot of reading to see, not only what you can and cannot accomplish, but what complexities you will be getting yourself into. It's not a particularly difficult technique at a basic level, but to get the most out of your money and equipment you really need to understand more than just the basics.

Here is an Olympus page with several articles you should study. Consider it only a start: https://www.olympus-lifescience.com/en/ ... c/dichome/

Tom

thomas.schwarz
Posts: 121
Joined: Tue Aug 27, 2019 5:04 pm

Re: There is DIC, then there is DIC

#11 Post by thomas.schwarz » Sun Dec 01, 2019 3:42 pm

Thanks Tom. Very clear and informative.

Post Reply