MicrobeHunter.com Microscopy Forum

When I took these images I probably was not using an NFK relay lens -- I'm not certain. It's not in my notes.

Are you using an NFK in your set-up? There are corrections done for these New(D/S)Plan objectives. But I doubt that would fix anything. Still it's something to ask about, especially since I think I skipped that option.

The other thing though is, I think for these 10x's it's possible I used a newer MPlan 10x BD shown in a picture of the turret posted in this thread earlier. I do have a 10x NeoDPlan that matches the others pictured. But the newer one is in the picture so I might have used that.

I also have an older Olympus DIC adapter that sits on the dovetail where the epi hooks up. The epi would then hook up above when the adapter was used. I don't think I have images in my notes for that. But I'd be curious to test it.

I do have AX's and BX's I'm setting up with U-DICT sliders. In the next couple months I could test image those reflectance and maybe transmission. If someone has some good test cases for transmission, I'd like to try to get comparison images.

Is there a way to make a dozen of something for a transmission test? I'd like to then share that type of slide. Calibration and microchips could be used to share a test for reflectance.

My first images were taken with an NFK relay (and viewed through WK eyepieces), which alas didn't help as you guessed.
I guess some sort of objective-prism mismatch might be possible. I'll have to dig a little deeper in the manual to see if perhaps these are the wrong prisms for these objectives after all, even though they do seem correct.

Attached is a picture of the manual (pdf link given below) that shows the older DIC nose prisms, but they had M and N series. M seems like metallurgical maybe?

https://www.atecorp.com/atecorp/media/p ... ochure.pdf

So for the newer ones (pictured below not from a manual), are these the valid prisms for reflectance? As they seem to have a double image problem. Are reflectance DIC prisms not trying to align with the objective's back plane? Since Olympus did sell a DIC adapter that sat above the turret, the distance for that prism was not guaranteed or adjustable height wise.

Thanks! Any added info is appreciated.
I do wonder what the 'T-2' and 'T-4' designations on my prisms mean. I think I have seen pictures without them too?
I did a test today with my splan 20x and mitutoyo 20x, and the degree of doubling really seemed identical between the two. But detailed industrial documentation is always hard to come by, if it ever existed.
I think it may come down to being careful about what I shoot with it. Angular or point features suffer from doubling while smoother ones don't quite as badly.
Anyway, epi pol has done very well for me in some cases too. It's not DIC but it is nice.

I wonder if the T is for transmission, and these prism are not for reflectance. But I haven't found the equivalent M or R that should also exist. Or a dovetail adapter to put under the epi.

For BX2 there are two objective turret DIC prims, one for transmission and one for reflectance.

It would explain thinga but I don't think it's possible--these are natively m26 thread, which I think olympus only ever used for bf/df objectives (and only in this era too?). Still, it is a real headscratcher.

This BH2-MJL set up for reflectance DIC has objective prisms that look different from the older ones picture here in the pdf manual and the newer typical ones pictured earlier:

https://www.ebay.com/itm/Olympus-BH2-MJ ... 2630595943

So this manual shows the newer swing-out nose prism form factor on a BH3-MJL. There is no mention of a condenser prism, so just reflectance DIC: (http://www.alanwood.net/downloads/olymp ... ctions.pdf) as shown in this e-bay item: (https://www.ebay.com/itm/Olympus-BH3-MJ ... 4238447302)

Thanks for co tinung to dig on this! That ibtermediate style is really odd--mine are definitely the BH3 style.

I tried two other things today, varying the distance of thr objective from the prism and the rotational position of the prism. Distance didn't seem to do anything. Rotational position is just like rotating the polarizer, it removes doubling as well as DIC leaving only epi pol.

At this point I can't think of anything other than my prisms being bad, but they look fine and it seems to have affected all three almost equally.

I do notice when using epi illumination that when things move out of focus they seem to split as they blur. Not sure what's up with that but it doesn't affect normal picture taking.

Scarodactyl wrote: ↑

Sat Jun 27, 2020 5:22 am

At this point I can't think of anything other than my prisms being bad, but they look fine and it seems to have affected all three almost equally.

Have you tried turn the objectives a bit in place to see if adding distance might improve the image?

Scarodactyl wrote: ↑

Sat Jun 27, 2020 5:22 am

I do notice when using epi illumination that when things move out of focus they seem to split as they blur. Not sure what's up with that but it doesn't affect normal picture taking.

I noticed a very similar effect in the beginning when I was messing around with diy transmitted DIC with two identical Nikon epi DIC loan. At that point both my prisms were held in a very improvised way and were surely not properly orientated. I haven't experienced it to the same extent again now that my setup is more stable, but I can play around and try to see if I can reproduce that effect. If so, I might be able to deduce what the doubling comes from.

microb wrote: ↑

Sat Jun 27, 2020 7:21 am

Scarodactyl wrote: ↑

Sat Jun 27, 2020 5:22 am

At this point I can't think of anything other than my prisms being bad, but they look fine and it seems to have affected all three almost equally.

Have you tried turn the objectives a bit in place to see if adding distance might improve the image?

Yes, though only to a limited extent allowed by the length of the threads. It didn't seem to help.
I have noticed it is more pronounced on the 10x than the 20x, though it is clearly visible on both.
Hopefully widefield imaging via direct projection will make it proportionately less severe vs image size, which should help.
I just tried using a different, incomplete coaxial illuminator lit with my cell phone flashlight, and doubling looked identical. I think we can eliminate the illumination train as the source of trouble.

Sorry for the bump but just wondering if the problem might be the polarizer/analyzer not giving true extinction.

Is the reflector (semi mirror) a first surface mirror? Have you tried flipping the mirror?

Alas, I have already tested the polarizers, they seem to work perfectly and swapping one out got identical results. I also controlled for the epi illuminator in a couple ways.

I tried a few more things along the way, swapping out different polarizers (the rotating polarizer in the Olympus system is unusual, and doesn't behave the same as a Nikon labophot analyzer placed in the same slot--I don't know if it's a different orientation between the linear and quarter wave plate layers, or if it is actually a linear and elliptical polarizer (??).)

So I ended up finding a great deal on a Nikon finite optiphot with epi DIC prisms and have it almost fully assembled (just with bd 20x and 40x dic objectives so far). I still need to hook up a proper illuminator so this shot was taken using a flashlight. Nevertheless, guess what I saw:


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Scarodactyl wrote: ↑

Tue Aug 04, 2020 7:41 pm

(the rotating polarizer in the Olympus system is unusual, and doesn't behave the same as a Nikon labophot analyzer placed in the same slot--I don't know if it's a different orientation between the linear and quarter wave plate layers, or if it is actually a linear and elliptical polarizer (??).)

I may be way off in the weeds here, was just reading a bit about DIC, but does the quarter-wave plate stay in a fixed orientation relative to the microscope as the linear polarizer rotates? (As opposed to a circular polarizer which would have the relative orientation of the linear polarizer and quarter-wave plate fixed?) If so it looks like that would be called a de Sénarmont compensator? Have you seen the diagram "de Sénarmont Reflected Light DIC Configuration" on the Nikon MicroscopyU site?

Thr olympus system has one fixed quarter wave plate which you can insert or remove. The rotatable polarizer is, however, not just a linear polarizer. It has some sort of wave plate attached, which faces away from thr lamp in DIC mode (for pol mode you reverse the entire rotatable polarizer and it of course behaves like a linear polarizer in that orientation). So.... beats me. Thr nikon analyzer I tried in the slot is also a circular polarizer (presumably to depolarize the light after the linear polarizer works its magic to avoid issues in the head prisms). When I face the nikon analyzer with the quarter wave plate towards the objectives it doesn't do anything (as you'd expect). With the linear polarizing side towards the objectives it works just like the olympus in linear polarizer mode.

Scarodactyl wrote: ↑

Wed Aug 05, 2020 12:05 am

Thr olympus system has one fixed quarter wave plate which you can insert or remove.

Is this fixed one you are referring to in the tint plate slider that goes into a different slot than the polarizer?

Scarodactyl wrote: ↑

Wed Aug 05, 2020 12:05 am

The rotatable polarizer is, however, not just a linear polarizer. It has some sort of wave plate attached, which faces away from thr lamp in DIC mode

Some of the diagrams I saw seemed to imply that, within the polarization slider, the quarter-wave plate would be fixed to the frame of the slider and only the linear polarizer would actually rotate, thus forming a de Sénarmont compensator.

Scarodactyl wrote: ↑

Tue Aug 04, 2020 7:41 pm

So I ended up finding a great deal on a Nikon finite optiphot with epi DIC prisms and have it almost fully assembled (just with bd 20x and 40x dic objectives so far). I still need to hook up a proper illuminator so this shot was taken using a flashlight. Nevertheless, guess what I saw:

So are you switching to the Nikons in lieu of the Olympus Neo DICs?

I'm not sure how it will shake out--I'll have to see if performance on the Nikon is actually better in practical terms (and how the 10x and 5x objectives are), but I am guessing it is not or not by much. I will probably finish assembling it and sell it.

My ideal case is to find some that work well with my mitutoyo objectives--the Olympus ones are so close, since they work almost as well on the mitties as with the original olympus objectives, just with that same doubling. The Nikons have a compatible m26 thread as well but the doubling will probably mean that this won't be better evem if they also work with the mitutoyos. Plus the Olympus illuminator is just really really nice for non-DIC so giving that up would be hard.

Scarodactyl wrote: ↑

Thu Aug 06, 2020 11:08 pm

My ideal case is to find some that work well with my mitutoyo objectives--the Olympus ones are so close,

Were any of the double-blur images from Mitutoyo's?

I try to restrict testing to the neo splans to remove that variable. I did do a couple tests where I swapped objectives on the same subject to see if the presence or degree of doubling varied at all and it unfortunately did not.

I was fixing up a BHM scope today, Stephen, and noticed a few things about the NeoSplan objective markings. I'm wondering if there might be some incompatibilities between prisms and objectives??

Things noticed about the NeoSPlan BF/DF objectives:

- Some prisms were labelled with no "T-x" markings, several with "T-2" and one with "T4-2."
- One objective was marked "T-6" before the usual serial number and another (on the T-4 prism) was marked "T-4."
- Numerical apertures changed a few times on some objectives; not sure of the sequence
- Generally (according to my BHM catalog) some objectives marked "NIC" had slightly lower numerical apertures in the 20x and 50 magnifications
- However, I had one 20x not marked NIC with a 0.40na and one marked NIC with a 0.46na.
- My two 50x were 0.80na for the regular one and 0.70na for the 50x also marked NIC. However the 0.80na actually worked better on NIC than the one supposedly for NIC.
- While all the glass looked clear of scratches, mold, etc. - two objectives were inexplicably poorer than the others. Softer image, remedied only by way stopping down.

Given the rapid change in the semiconductor industry and all scope vendors quickly changing models, wonder if Olympus managed to change lens specs enough to result in incompatibilities if someone tries to piece together a system? The only documentation I've seen on these objectives was in a BHM scope manual and it doesn't mention anything about the various T-2, T-4, T-6 designnations, why they dropped the 40x NeoSPlan (rarely seen, mostly 50x), why the changes in numerical aperture, etc.

It is a true black box (like most industrial systems of that era). I actually didn't piece this one together, it came as a full system amazingly enough (rare deal!) and even survived shipping with inadequate packaging just fine.

Even more confusing, most other systems I've been able to scope out seem to mix the various T designations freely. These are not hard to mix and match on a nosepiece though so who knows what their history is.

Still, somehow I don't think it's an objective mismatch. The fact that my mitutoyos get identical doubling suggests to me that more minor inter-series variations wouldn't affect it much either. I'll have to try whatever else I have lying around, though I think I also used one of my nikon 20xes and it also had the same doubling.

Speaking of Nikon, the optiphot showing the same issue was something of a bummer. I know a guy with access to a modern LV series eclipse with epi DIC and he said it shows some doubling too (noticeably, and in contrast to others he'd tried that did not). I have come to suspect it really is just i herent to the prisms.

Maybe I should get a balplan DIC attachment and adapt it on.

I wonder if the double images are coming from the mirror (reflecting light down, passing it up)? Perhaps some bit of fume or dust has attached itself over the years or?? Possibly also an artifact of the illuminator not presenting a near perfectly parallel source where it hits the mirror- though you'd tried stopping the iris down and sill got the double image?

Wondering if you could try illuminating the specimen with external lamps and pulling the half-silvered mirror out of the path - just leaving the DIC prisms. Are there still double images?? If so, that seems to implicate the prisms. If not, or reduced, maybe the mirror or illumination is the problem? Maybe a slight haze gradually accumulated scattering the light a bit??

My vertical illuminator is of the type shown below. Compared to some of the others it seems relatively well sealed - and in at least casual visual observation I'm not seeing the doubling.

All that said, most of my specimens are relatively flat (metals, wafers, print, etc.) - your reflective geo/gemological specimens maybe present special difficulties??

As a wild possibility, the illuminating beam is sheared by the DIC prism on the way to the specimen. It's supposed to be sheared back pretty much in place on the way up. However, the highly reflective and odd angles of your diamond just might scatter that sheared illumination beam in ways not anticipated??

Illuminator type I'm using:

https://www.ebay.com/itm/Olympus-BH2-Mi ... SwdHtesd13

Stephen, I was checking out an Olympus reflected DIC setup today, using infinity MSPlans rather than NeoSplans, and noticed a double image of the field diaphragm. Most of this could be eliminated by realigning the illuminator tube. There are three setscrews for centration at two locations back on the illuminator tube. Might be worth a check?

FWIW, I've found that Olympus' infinity MSPlans work well on their previous generation DIC prisms (meant for MPlans). Also played around trying a biological specimen (dried blood cells, no cover) by backing the slide with a reflected layer and by using a combination of reflected and transmitted light. Somewhat promising.

That's interesting! I did go through the process of centering the bulb as the manual laid out and it didn't seem to change anything but I'll have to give it another shot.

FWIW, the bulb location (inside the lamp house) wasn't my problem. For this particular illuminator all that seemed to affect was the brightness achieved on the stage; not the double iris image.

It was the centratiion (three screws) closes to where the illuminator tube enters the epi intermediate adapter. I could clearly see two images of the field iris. One bright, the other maybe 20% bright. Don't know if it's the answer to your double images, but maybe a factor?

Ah, ok I'll have another look at that tomorrow. I did have a look at the field stop and it didn't seem to show doubling but it's hard to tell.
Plus sdie, even with some doubling there are subjects it is good for:

Doubling is still there but doesn't matter as much for a smooth subject like the bubbly/botryoidal back of a silicon chip.
(shot with a Nikon e plan epi 50x I happened to have on the nosepiece to test).