PlasDIC

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crb5
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PlasDIC

#1 Post by crb5 » Tue Dec 29, 2020 12:00 am

A colleague of mine recently obtained a Leitz Laborlux S scope on eBay which came with a PlasDIC option. He asked me to take a look at it and try it out. The scope has a slider above the objectives which appears to be a prism+polarizer. I was expecting a second polariser above this, as in the Zeiss PlasDIC system http://www.zebrasc.com/UpImages/200912/ ... 132510.pdf but there is no port available. There is a 3.5mm slit aperture in a plastic holder which sits centrally over the light source, and immediately above this there is a rotatable polarizer. I thought PlasDIC referred to the option of being able to use PLASTIC sample dishes and for this there should not be any polarizers in the illumination path - but on closer investigation I see other authors (theoreticians at least!) have described the arrangement above as PlasDIC e.g. https://onlinelibrary.wiley.com/doi/abs ... /jmi.12248. It therefore seems some people use PlasDIC to describe the situation where a slit aperture is used. There is no indication on the prism slider as to which objective it is designed for. The scope has 4x, 10x and 40x 160/0.71 objectives plus a 25x 170/0.71 objective - the latter suggests the scope has been subject to add-ons, nor is it clear where the PlasDIC slider came from or if this is a DIY modification. Any advice on how to use such a system? I did not get particularly impressive DIC-like effects with an onion skin test sample as I rotated the slit+polarizer (i.e. oblique illumination seemed to work just as well).

lightshape
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Re: PlasDIC

#2 Post by lightshape » Sat Jan 09, 2021 8:36 pm

Hi,

you are right regarding polarizer/analyzer position and PlasDIC.
For PlasDIC you will usually find objective specific prisms and the polarizer and analyzer are both placed behind the sample.

There once was an article in a german microscope magazine:
https://www.zobodat.at/pdf/Mikrokosmos_72_0001.pdf
..page 301

Guess this could in fact be a DIY slit DIC you've got.
In such a setup, one prism might work well for many different magnification combinations.
But, you will have to adjust the size of the slit to match the magnifications or even more specific, to the used prism and objectives themselves for best results.

Some measures to begin experimenting with slits:
10x 1-2mm
40x 3-6mm
100x 5-10mm

For the slit, once adjusted, you don't want to rotate it at all.
It needs to be perfectly aligned with the optical axis of the DIC Prism.
Which is 45° in respect to the axis of the polarizer.
Also, as far as i know, the slits positioning then needs to be covering the extinction pattern of the Prism (the black slit you will see on the DIC prism placed between polarizer/analyzer in extinction).

Has the analyzer above the Prism been fixed?
If so, chance are great it will still be correctly aligned to the prism, this would already make things little easier to start.

Hope this takes you a little further.

crb5
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Re: PlasDIC

#3 Post by crb5 » Sat Jan 09, 2021 11:16 pm

Thanks for the information and article. This does suggest the supplied slit is designed to be used with the 40x objective and knowing the slit should be 45 degrees to the polariser is helpful. The analyzer and wollaston prism in the imaging path are fixed, so that just leaves the illumination polarizer to be adjusted.

Scarodactyl
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Re: PlasDIC

#4 Post by Scarodactyl » Sun Jan 10, 2021 12:21 am

Please share some pictures if you get it up and running. Epi DIC systems are way easier to find bargains on than transmitted, so this technique seems like it should be of great interest if it can deliver.

PeteM
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Re: PlasDIC

#5 Post by PeteM » Sun Jan 10, 2021 12:29 am

Curious if this microscope came from a Canadian Ebay seller? I've seen a number of microscopes described as "DIC" or Plas-DIC" from that source that look to have been cobbled together, with not quite enough parts. Could be it's just a sort of oblique setup, maybe with a prism added to add some color?? The same seller has advertised as "phase contrast" an objective not so marked and with no phase ring looking through.

Elapid
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Re: PlasDIC

#6 Post by Elapid » Tue Mar 02, 2021 11:49 am

I agree, the Canadian seller seems to specialize in “pseudo-DIC” microscopes which give a false impression of DIC by using polarization in one form or another. If you look at one of seller’s scopes on eBay you will see a photo in the lineup which supposedly was taken thru the scope currently for sale. It is a true DIC photomicrograph but the very same photo appears with every one of seller’s listed DIC scopes! I discovered this the hard way. I wish eBay would crack down on this sort of thing but it would be very difficult for a buyer to initiate.

apochronaut
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Re: PlasDIC

#7 Post by apochronaut » Wed Mar 03, 2021 9:33 pm

PeteM wrote:
Sun Jan 10, 2021 12:29 am
Curious if this microscope came from a Canadian Ebay seller? I've seen a number of microscopes described as "DIC" or Plas-DIC" from that source that look to have been cobbled together, with not quite enough parts. Could be it's just a sort of oblique setup, maybe with a prism added to add some color?? The same seller has advertised as "phase contrast" an objective not so marked and with no phase ring looking through.
There are phase contrast objectives that do have a phase ring that is not visible to the eye.

PeteM
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Re: PlasDIC

#8 Post by PeteM » Wed Mar 03, 2021 10:19 pm

Could be. But the exterior markings on this one (being sold as phase) said nothing about phase, ph, ph1, dm, etc. etc. I was inclined towards skepticism - warranted or not. When asked the seller basically said "I don't know . . ."

LouiseScot
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Re: PlasDIC

#9 Post by LouiseScot » Sun Mar 07, 2021 8:59 pm

There's currently a plasDIC slider on Ebay and from Denmark. Says it's for a 20x objective with coverslip correction. If I thought I could get it to work I'd be tempted to buy it and have a go!

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Placozoa
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Re: PlasDIC

#10 Post by Placozoa » Mon Mar 08, 2021 4:51 am

https://www.ebay.at/itm/PlasDIC-slider- ... SwlTBeI0~7

Something like that?

Im reasonably sure you need a matching prism in your condenser for it to work. The DIC prisms may also need to be preceded by a polarizer, but that may be built in to the condenser. Others would know better, I dont have DIC.

LouiseScot
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Re: PlasDIC

#11 Post by LouiseScot » Mon Mar 08, 2021 8:27 am

Placozoa wrote:
Mon Mar 08, 2021 4:51 am
https://www.ebay.at/itm/PlasDIC-slider- ... SwlTBeI0~7

Something like that?

Im reasonably sure you need a matching prism in your condenser for it to work. The DIC prisms may also need to be preceded by a polarizer, but that may be built in to the condenser. Others would know better, I dont have DIC.
Yeah, that's the one. I was looking at it from the point of view of the figures showing the principles here: http://www.zebrasc.com/UpImages/200912/ ... 132510.pdf

They suggest a slit then a polariser/prism/analyser above the objective, which could be done on my customisable rail system. But, together with a matching objective, it would still be a lot of money to risk! Though great if it worked :)

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

apochronaut
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Re: PlasDIC

#12 Post by apochronaut » Mon Mar 08, 2021 11:51 am

PlasDIC is just one named system that Zeiss named and I'm pretty sure patented. It was derived from the designs of Max Pluta upon which PZO's several interference contrast systems were based. Zeiss used a workaround of the original system and came up with PlasDIC.
PlasDIC uses a slit diaphragm below the condenser and a cemented polarizer wollaston prism slider above the objective followed by an analyzer. Pluta's design used a polarizer and variable slit condenser below the condenser , then a prism and analyzer above the objective. There was also a 3-D condensing system by Goerz that used a polarizer and some sort of prism/slit condenser below the stage and an analyzer above the objective. Both Pluta's and Goerz' systems could be operated at high magnification, whereas PlasDIC seems to have a limit around a 40X objective. That may be due to the targeted application of plastic dishes. Perhaps with glassware of a higher specification , one could go higher with PlasDIC.
There are several ways of getting a budget DIC system going but they all seem to hinge on the utilization of a slit diaphragm BELOW the condenser. The PZO version is deformable and the Goerz version rotatable. Aligning the slit with the polarizer is necessary. In the PZO version the polarizer rotates against the diaphragm.

LouiseScot
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Re: PlasDIC

#13 Post by LouiseScot » Mon Mar 08, 2021 12:59 pm

apochronaut wrote:
Mon Mar 08, 2021 11:51 am
PlasDIC is just one named system that Zeiss named and I'm pretty sure patented. It was derived from the designs of Max Pluta upon which PZO's several interference contrast systems were based. Zeiss used a workaround of the original system and came up with PlasDIC.
PlasDIC uses a slit diaphragm below the condenser and a cemented polarizer wollaston prism slider above the objective followed by an analyzer. Pluta's design used a polarizer and variable slit condenser below the condenser , then a prism and analyzer above the objective. There was also a 3-D condensing system by Goerz that used a polarizer and some sort of prism/slit condenser below the stage and an analyzer above the objective. Both Pluta's and Goerz' systems could be operated at high magnification, whereas PlasDIC seems to have a limit around a 40X objective. That may be due to the targeted application of plastic dishes. Perhaps with glassware of a higher specification , one could go higher with PlasDIC.
There are several ways of getting a budget DIC system going but they all seem to hinge on the utilization of a slit diaphragm BELOW the condenser. The PZO version is deformable and the Goerz version rotatable. Aligning the slit with the polarizer is necessary. In the PZO version the polarizer rotates against the diaphragm.
Thanks for the info! It wouldn't be difficult to arrange a slit. It's not clear to me what the relationship is between the objective and the prism. In the Ebay ad you can see it specifies a 20x objective -> 'PlasDIC slider for LD PN 20x/0.40 corr' which is a long working distance objective that has a cover slip corrector (perhaps for an inverted microscope?). Also quite expensive in itself, and it's not clear to me whether that should be a phase contrast (Ph1) version? I'd have thought phase contrast was quite separate from plasDIC?
So I presume a standard 20x objective would do, but it's also implied that you'd need a separate prism slider for each objective? That wouldn't be good but, if I had such a thing, I'd probably only use it/them with 20x and 40x.

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

viktor j nilsson
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Re: PlasDIC

#14 Post by viktor j nilsson » Mon Mar 08, 2021 1:33 pm

The two key variables to be optimized is the shear angle and location of the interference fringe. The shear angle is optimized based on the NA of the objective, with narrower angles for high NA/high magnification objectives. I think that it is correct to say that this is because you want the separation created by the shear angle to be smaller than the minimum resolvable feature of the objective. The location of the interference fringe is optimized so that its location coincides with the back focal plane of the objective.

So in general, 20x prism = larger shear angle, interference fringe closer to the prism; 40x prism = smaller shear angle, interference fringe further from the prism.

In reality, these systems are fairly tolerant. You could probably pick almost any 10x,20x or 40x prism (epi, plasDIC or transmitted), a polarizer and test some differently-sized slits at the back focal plane of the condenser, and you would get a pretty decent plasDIC effect. If you can move the prism up and down a bit to match the back focal plane - even better.

I do not think that the prism on eBay is necessarily better suited for DIY plasDIC than other nomarski prisms intended for other dic methods.

LouiseScot
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Re: PlasDIC

#15 Post by LouiseScot » Mon Mar 08, 2021 1:37 pm

viktor j nilsson wrote:
Mon Mar 08, 2021 1:33 pm
The two key variables to be optimized is the shear angle and location of the interference fringe. The shear angle is optimized based on the NA of the objective, with narrower angles for high NA/high magnification objectives. I think that it is correct to say that this is because you want the separation created by the shear angle to be smaller than the minimum resolvable feature of the objective. The location of the interference fringe is optimized so that its location coincides with the back focal plane of the objective.

So in general, 20x prism = larger shear angle, interference fringe closer to the prism; 40x prism = smaller shear angle, interference fringe further from the prism.

In reality, these systems are fairly tolerant. You could probably pick almost any 10x,20x or 40x prism (epi, plasDIC or transmitted), a polarizer and test some differently-sized slits at the back focal plane of the condenser, and you would get a pretty decent plasDIC effect. If you can move the prism up and down a bit to match the back focal plane - even better.

I do not think that the prism on eBay is necessarily better suited for DIY plasDIC than other nomarski prisms intended for other dic methods.
But other DIC uses two prisms and anything labelled 'Nomarski' seems to be very expensive!

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

viktor j nilsson
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Re: PlasDIC

#16 Post by viktor j nilsson » Mon Mar 08, 2021 1:47 pm

LouiseScot wrote:
Mon Mar 08, 2021 1:37 pm
viktor j nilsson wrote:
Mon Mar 08, 2021 1:33 pm
The two key variables to be optimized is the shear angle and location of the interference fringe. The shear angle is optimized based on the NA of the objective, with narrower angles for high NA/high magnification objectives. I think that it is correct to say that this is because you want the separation created by the shear angle to be smaller than the minimum resolvable feature of the objective. The location of the interference fringe is optimized so that its location coincides with the back focal plane of the objective.

So in general, 20x prism = larger shear angle, interference fringe closer to the prism; 40x prism = smaller shear angle, interference fringe further from the prism.

In reality, these systems are fairly tolerant. You could probably pick almost any 10x,20x or 40x prism (epi, plasDIC or transmitted), a polarizer and test some differently-sized slits at the back focal plane of the condenser, and you would get a pretty decent plasDIC effect. If you can move the prism up and down a bit to match the back focal plane - even better.

I do not think that the prism on eBay is necessarily better suited for DIY plasDIC than other nomarski prisms intended for other dic methods.
But other DIC uses two prisms and anything labelled 'Nomarski' seems to be very expensive!

Louise
Yes, but the upper prism in a transmitted Nomarski DIC system needs to fulfill the exact same requirements: a shear angle that matches the NA of the objective, and an interference fringe that matches the location of the back focal plane. So there's nothing special about plasDIC prisms.

The plasDIC is simple to DIY, since those are the only parameters you need to optimize (well that, and the width of the slit). And it's probably not even super critical to get them just right.

In a true Nomarski DIC system, you also need to make sure that the width of the interference bands created by the condenser prism (after passing through both the condenser and the objective) matches the width of the Interference bands created by the upper prism. And that's a whole lot more complicated.

LouiseScot
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Location: Scotland

Re: PlasDIC

#17 Post by LouiseScot » Mon Mar 08, 2021 1:54 pm

viktor j nilsson wrote:
Mon Mar 08, 2021 1:47 pm
LouiseScot wrote:
Mon Mar 08, 2021 1:37 pm
viktor j nilsson wrote:
Mon Mar 08, 2021 1:33 pm
The two key variables to be optimized is the shear angle and location of the interference fringe. The shear angle is optimized based on the NA of the objective, with narrower angles for high NA/high magnification objectives. I think that it is correct to say that this is because you want the separation created by the shear angle to be smaller than the minimum resolvable feature of the objective. The location of the interference fringe is optimized so that its location coincides with the back focal plane of the objective.

So in general, 20x prism = larger shear angle, interference fringe closer to the prism; 40x prism = smaller shear angle, interference fringe further from the prism.

In reality, these systems are fairly tolerant. You could probably pick almost any 10x,20x or 40x prism (epi, plasDIC or transmitted), a polarizer and test some differently-sized slits at the back focal plane of the condenser, and you would get a pretty decent plasDIC effect. If you can move the prism up and down a bit to match the back focal plane - even better.

I do not think that the prism on eBay is necessarily better suited for DIY plasDIC than other nomarski prisms intended for other dic methods.
But other DIC uses two prisms and anything labelled 'Nomarski' seems to be very expensive!

Louise
Yes, but the upper prism in a transmitted Nomarski DIC system needs to fulfill the exact same requirements: a shear angle that matches the NA of the objective, and an interference fringe that matches the location of the back focal plane. So there's nothing special about plasDIC prisms.

The plasDIC is simple to DIY, since those are the only parameters you need to optimize (well that, and the width of the slit). And it's probably not even super critical to get them just right.

In a true Nomarski DIC system, you also need to make sure that the width of the interference bands created by the condenser prism (after passing through both the condenser and the objective) matches the width of the Interference bands created by the upper prism. And that's a whole lot more complicated.
Yeah, I wouldn't attempt any kind of DIY full DIC, lol.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Elapid
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Re: PlasDIC

#18 Post by Elapid » Sat Mar 13, 2021 1:41 pm

I spent years searching for a “cheap” DIC scope and wasted time and money without any real results. Last year I decided to bite the bullet and spend the money to get a true DIC microscope. Now I realize that true DIC microscopy is a thing of beauty, DIC photomicrographs can be quite stunning, especially with focus stacking. But DIC is complex and exacting. I’ve noticed that the Chinese microscope companies don’t seem to offer it. My scope requires a polarizer below the condenser, prisms in the condenser for each objective, and then the prism/polarizer analyzer below the eyepieces. If any of these components are missing or not properly adjusted then DIC is lost. Unfortunately this is all very expensive to manufacture and expensive to buy even on the used market. But worth the wait. At one point I let myself be deceived into buying a pseudo-DIC scope, but at least it was a good learning experience. Finally getting the real thing was worth the wait.

LouiseScot
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Re: PlasDIC

#19 Post by LouiseScot » Sat Mar 13, 2021 2:05 pm

Elapid wrote:
Sat Mar 13, 2021 1:41 pm
I spent years searching for a “cheap” DIC scope and wasted time and money without any real results. Last year I decided to bite the bullet and spend the money to get a true DIC microscope. Now I realize that true DIC microscopy is a thing of beauty, DIC photomicrographs can be quite stunning, especially with focus stacking. But DIC is complex and exacting. I’ve noticed that the Chinese microscope companies don’t seem to offer it. My scope requires a polarizer below the condenser, prisms in the condenser for each objective, and then the prism/polarizer analyzer below the eyepieces. If any of these components are missing or not properly adjusted then DIC is lost. Unfortunately this is all very expensive to manufacture and expensive to buy even on the used market. But worth the wait. At one point I let myself be deceived into buying a pseudo-DIC scope, but at least it was a good learning experience. Finally getting the real thing was worth the wait.
PlasDIC is a genuine contrast enhancement technique developed by Zeiss https://www.emerald.com/insight/content ... /full/html
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

crb5
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Re: PlasDIC

#20 Post by crb5 » Sat Mar 13, 2021 3:58 pm

LouiseScot wrote:
Sat Mar 13, 2021 2:05 pm

PlasDIC is a genuine contrast enhancement technique developed by Zeiss https://www.emerald.com/insight/content ... /full/html
This takes us back to my opening question. The Zeiss PlasDIC system has no polarizing components in the illumination/condenser pathway which allowed PLAStic dishes to be used with samples (the technique was developed with in vitro fertilisation in mind). However, the add-on version on my colleague's Leitz Laborlux S scope had a polarizer and slit which sits above the light source and precludes the use of plastic dishes. I subsequently found that this arrangement has also been called PlasDIC in some literature and I wondered how this could be. This same colleague has now bought a Nikon Microphot FXA with Nomarkski DIC and seems very pleased with it. Me, I'm sticking with my Amscope 120 and Dodt contrast for free.

LouiseScot
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Re: PlasDIC

#21 Post by LouiseScot » Sat Mar 13, 2021 4:35 pm

crb5 wrote:
Sat Mar 13, 2021 3:58 pm
LouiseScot wrote:
Sat Mar 13, 2021 2:05 pm

PlasDIC is a genuine contrast enhancement technique developed by Zeiss https://www.emerald.com/insight/content ... /full/html
This takes us back to my opening question. The Zeiss PlasDIC system has no polarizing components in the illumination/condenser pathway which allowed PLAStic dishes to be used with samples (the technique was developed with in vitro fertilisation in mind). However, the add-on version on my colleague's Leitz Laborlux S scope had a polarizer and slit which sits above the light source and precludes the use of plastic dishes. I subsequently found that this arrangement has also been called PlasDIC in some literature and I wondered how this could be. This same colleague has now bought a Nikon Microphot FXA with Nomarkski DIC and seems very pleased with it. Me, I'm sticking with my Amscope 120 and Dodt contrast for free.
I think, as Apo pointed out, there are several versions of the idea. Much as I'd like proper DIC I can't afford it. Much as I'd like to experiment with some form of plasDIC, that's not cheap either, and I don't think I'd want to risk spending a fair bit of money on experimenting. I just posted the comment above to indicate that plasDIC is a genuine technique. I doubt I'll be pursuing it any further myself but would be interested if someone else does achieve decent results with it :)

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Scarodactyl
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Re: PlasDIC

#22 Post by Scarodactyl » Sat Mar 13, 2021 11:18 pm

There's an epi dic slider attachment for a balplan available for like 300 bucks on some dealer's site. My own dic balplan gives very respectable epi DIC, similar to an Olympus bh2 era system, so I suspect it would be a good candidate for experimentation.

LouiseScot
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Re: PlasDIC

#23 Post by LouiseScot » Sat Mar 13, 2021 11:25 pm

Scarodactyl wrote:
Sat Mar 13, 2021 11:18 pm
There's an epi dic slider attachment for a balplan available for like 300 bucks on some dealer's site. My own dic balplan gives very respectable epi DIC, similar to an Olympus bh2 era system, so I suspect it would be a good candidate for experimentation.
That's only for opaque subjects though?
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

Scarodactyl
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Re: PlasDIC

#24 Post by Scarodactyl » Sun Mar 14, 2021 1:02 am

As configured yes, but if you put it on a transmitted light balplan (also not too expensive to get) it would probably be a good platform for experimenting with home made plasdic. I mwntion its epi performance only to establish it is a legit (if obscure) DIC system with a legit prism slider.

Dubious
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Re: PlasDIC

#25 Post by Dubious » Sat Jun 12, 2021 7:18 pm

So, I am confused. In this Ebay listing for a Reichert MicroStar IV with a PlasDIC slider above the objective turret (presumably the slit diaphram and polarizer are somewhere below?) is that an original Reichert option or something the microscope was modified for later that is unlikely to deliver DIC?

https://www.ebay.com/itm/264388794011?h ... SwmrVdH6y0

PlasDIC sounds like a somewhat forgiving type of DIC, more suited for a general application microscope. I'm surprised the Chinese manufactures aren't in the DIC market, but maybe it's a small market.

Scarodactyl
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Re: PlasDIC

#26 Post by Scarodactyl » Sat Jun 12, 2021 7:38 pm

That guy uses thr same "dic" photo for every listing from what I can see. I would never buy from him.

dtsh
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Re: PlasDIC

#27 Post by dtsh » Sat Jun 12, 2021 10:07 pm

Dubious wrote:
Sat Jun 12, 2021 7:18 pm
So, I am confused. In this Ebay listing for a Reichert MicroStar IV with a PlasDIC slider above the objective turret (presumably the slit diaphram and polarizer are somewhere below?) is that an original Reichert option or something the microscope was modified for later that is unlikely to deliver DIC?

https://www.ebay.com/itm/264388794011?h ... SwmrVdH6y0

PlasDIC sounds like a somewhat forgiving type of DIC, more suited for a general application microscope. I'm surprised the Chinese manufactures aren't in the DIC market, but maybe it's a small market.
I can't seem to find the thread, but there's a thread here where that very microscope gets discussed. While there are Nomarski DIC options for the 410, this one seems to be some sort of amalgamation of parts of various scopes, the nose appears to be a series 10 for example, that suggest it's someone's custom cobbling. I don't know enough to evaluate if it *works* or not, but I feel confident in saying it's not an original Reichert/Leica/Cambridge/AO option.

Edit: I recall the low effort spray paint job on the nose not instilling confience in attention to detail either. Still, it could work for all I know, but I'd be asking a lot of questions!

Dubious
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Re: PlasDIC

#28 Post by Dubious » Mon Jun 14, 2021 3:11 am

Looking at the photos again, I see what you mean. And I haven't been able to find any photos of new models equipped like that. Still, it would be great if some refurbisher had found an (almost) economical way to add plasDIC to the microscope, so after I know more about plasDIC, I may ask him those questions.

Scarodactyl
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Re: PlasDIC

#29 Post by Scarodactyl » Mon Jun 14, 2021 3:55 am

Look at his feedback too.

apochronaut
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Re: PlasDIC

#30 Post by apochronaut » Mon Jun 14, 2021 3:36 pm

I think what is being forgotten here is that at a certain point in time, the Buffalo factory had a best before date, or a limited shelf life, as it were. It was producing Microstar IV and Diastars until about 2001, ATC 2000s until somewhat later but the factory was sold. It continued to do service afterwards and the ATC 2000 production went to India. .They no doubt had stock on hand of all kinds of items at the end. Some, I know for sure ended up at various dealers because I have seen it and some of it for sure was sold off by Reichert Technologies, which continued in Opthalmic research and equipment development as a separate company in the factory.
Some of it, I am pretty sure none of you even know existed, such as Hoffman objectives.
They never made a series 100 DIC: probably some prototypes though, and they only sold about 20 series 21 DIC scopes, so that probably soured them on DIC during the 100 series era. They might have had series 10 slider equipped nosepieces around and the condenser under that 410 looks suspiciously like one I have seen on a legitimate 420 DIC scope.

Whether the factory threw those components together at the end of the run : after all, it would have made sense to liquidate as much as possible, or someone bought all the equipment and assembled the system makes some difference. A factory hybrid might well work pretty good, a kind if d.i.y. job, maybe yes, maybe no. There is no reason to suspect not though, except based on the odd nature of the seller's various listings. Maybe he is a mad DIC scientist, toiling away in the lonely basement of a former 17th century monastery in La Belle Province, unrecognized, unappreciated, on the verge of a breakthrough, in French: if only he had a chance!
Those look like real AO parts, just kind of like they had been assembled in a Renault factory. I'd like to try one out but not for 1000.00.

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