Dusty Diastar

[Plasmid]

Yesterday I embarked on a 8 hr road trip to pick up a Microscope I purchased online...I figured gas would be $50 , the same the seller was charging for shipping, but the chances of the microscope making in one piece via the US postal service were slim at best.
Since I started in this hobby I've always wanted a Diastar, theres just something about the design that screams remember the 80's.
This unit was cheap and blind ( no optics) and oh boy was it in bad shape, I got home and immediately took it completely apart here are some of the issues.

Dust., Dust and dust on top of the dust

The Cas200 box left some scratches on the top black cover, Im guessing years of use and the thing freely swinging around being held by the dovetail.

The filter wheel was very dusty, I punched the pin that holds the 3 wheels in place and started to clean the filter, much to my surprise the tension rings that hold the filters in place are corroded and fell apart, so Im not sure on how to permanently hold the filters on the slots. Advise is welcomed.

The nosepiece bearings were grinding, I had never taken one of those apart.....so needless to say all of the 20 bearings went flying in all directions, I cleaned and applied Nyogel and its butter smooth now.

Looking at the pics prior to purchase I was under the notion that all Diastars came with the nosepiece slot for DiC or PoL filters, but that's not the case.

I need to figure out how to removed the diffuser knob apart , im getting a lot of resistance on the actual knob, grease looks to be dried in there, I believe I have to remove the plastic cover around the knobs on the exterior in order to take it apart?!?! But im afraid pf braking the plastic cover.

I need to find a way to print a Diastar label for the body since the one on the right side is missing ( my OCD wont allow me to let it go)

Oddly enough I found a compartment below the stage that houses two small batteries...Im guessing part if the CAS system?

The coarse focus on the right wiggles....the plastic thats flushed against the body, I cane across this problem before with a Microstar...If i remember correctly one if the two screws that sit internally end up stripping the plastic , should be an easy fix.

Another odd sitting was the stage rack and carrier, a lot different then the ones I've seen (thinner) and no spring.the stage hight adjustment is controlled via allen key instead of the lever that normally the there!

The Condenser a 1201 has a plastic insert on the bottom that decrease the aperture....never seen that before , just like the filter that sits on top of the field lens ..... anyone knows what they're for?

[Plasmid]

... continued

I still have to take the head part and tale my time cleaning it, theres a lot of particles in the FOV

I also plan on taking the Cas200 box apart to see if it will aide in projek Frankenstar.. adapting the vertical illuminator from the Laborlux onto a 400 unit.


The carousel filter Wheels works wonders in trying to get that DIC / oblique look
20X "Chilympus" acro

[dtsh]

(for whatever reason, I didn't see any images when I replied...)

Yesterday I embarked on a 8 hr road trip to pick up a Microscope I purchased online...I figured gas would be $50 , the same the seller was charging for shipping, but the chances of the microscope making in one piece via the US postal service were slim at best.
Since I started in this hobby I've always wanted a Diastar, theres just something about the design that screams remember the 80's.

Ok, I am jealous.

The filter wheel was very dusty, I punched the pin that holds the 3 wheels in place and started to clean the filter, much to my surprise the tension rings that hold the filters in place are corroded and fell apart, so Im not sure on how to permanently hold the filters on the slots. Advise is welcomed.

I feel like a broken record on a lot of these types of things, but 3D print a replacement retaining ring? Now that I can see the images, perhaps a bit of spring wire as would retain a reticle in an eyepiece? Inexpensive, yet functional.

The nosepiece bearings were grinding, I had never taken one of those apart.....so needless to say all of the 20 bearings went flying in all directions, I cleaned and applied Nyogel and its butter smooth now.

I have one in which the steel bands/races above and below the bearing holder were dented in a few places from what I presume was a hard knock. I found that flipping them over allowed the bearings to have smooth races again in case yours is exhibiting anything similar. I haven't checked the runout on it yet, probably should....

The coarse focus on the right wiggles....the plastic thats flushed against the body, I cane across this problem before with a Microstar...If i remember correctly one if the two screws that sit internally end up stripping the plastic , should be an easy fix.

I haven't dismantled the focus on a 410/420 so can't help, but I have one which will need some service so will be watching for tips....

Another odd sitting was the stage rack and carrier, a lot different then the ones I've seen (thinner) and no spring.the stage hight adjustment is controlled via allen key instead of the lever that normally the there!

That's how all 3 of my 410 stages are, one from a stand labelled as Reichert, one labelled as Leica, and the third is unknown (didn't come with a stand, just parts). On all of mine even the condenser stop is retained by an allen set screw.

The Condenser a 1201 has a plastic insert on the bottom that decrease the aperture....never seen that before , just like the filter that sits on top of the field lens ..... anyone knows what they're for?

No idea, neither of my 1201's appear to have such (one is mounted in a 1205 phase turret), I haven't seen such and I'm curious as to what it's function is.

I look forward to seeing more of the guts in the Diastar.

[apochronaut]

The Cell Analysis System used lower magnification objectives at least for some of it's purposes. CAS had AO/Reichert produce objectives for them, which were standard Reichert planachros but branded CAS. I have a 10X .25 and a 63X .80, so marked, the only ones I have ever seen. Oddly, the 63X is a cat.# 1303 34mm parfocal one, with an extension on it and a custom shroud that makes it look like a 45mm parfocal objective. The CAS system maybe utilized only a fairly narrow f.o.v. because the #1303 objective has fairly high lateral c.a. when used with the series 400 head. It is unuseable as a wide field objective but pretty good through the central field. Either that or they had an in/out optic for it in the system, since the CAS 10X is a standard #1732 planachro and requires slightly different corrections of the telan lens.
The system was semi-automated, requiring a microscopist but yielding computerized results. My guess is that a precise illuminating aperture and possibly filtering were critically necessary for best results in the system, so the diaphragm insert was a way of stabilizing the aperture at a desired N.A., which would have been .80, likely. I have only ever seen 10X .25 and 63X .80 objectives but there may be others.
I don't really know much about the system and it is quite antique and obsolete now, with regards to how cell analysis is done today.

Nice think is that the condenser might have been little touched, so the track and fork might be in top shape.
All Diastars I have seen have a spring loaded lever for the stage height whereas Microstar IV's have a hex screw. Probably, since that was destined to be a semi-automated microscope and there would be limited value in having an easily moveable stage, they put in some simpler and cheaper systems from the Microstar.
Does it have the stage locking thumbscrew and a 90° rotateable stage?
There are cast aluminum armrests you can fit into those aluminum channels on the side. Miller probably still has some. They wanted 60.00 pr. but perhaps they have discovered flexibility since then.

[wabutter]

The CAS Systems were developed for doing Ploidy analysis. By the time the CAS 200 was implemented they had fully integrated the OEM function of the AO/Reichert components by putting their own logo in place. They supported the entire platform. I forgot what the battery were for.
The condenser aperture was set to a fixed position to ensure repeatability, both in measurement and calibration. Stoichiometric stains were used in determining how much DNA was present in a group of cells and any change in the optical system from the calibration point would affect the output values.

[Plasmid]

Thank you everyone, I couldn't find much info on the web about the CaS system.

I took the box apart and found some interesting filters inside, not sure what they are. Pics below

I also had the crazy idea to modify the box, I plan on taking one of the cameras out and fixing a 3w laser or a UV source in it's place, not sure if it will need a dichroic mirror for the desired effect ... But what the heck I'll give a try to see if some light is transmitted, the objective should function as a a type of condenser, if not I'll will probably include another objective on the light path inside the box. I'll then test it on the Frankenstar.

[wabutter]

It appears there are two CCD cameras, and the filters were placed in front of each camera one red and one green. A rapid switching turret directed the light path between the two camera paths.

This is often a filter combination that is used when grayscale images are superimposed allowing the difference to be seen. Pure speculation, but I suspect that besides the Ploidy app there was another app with the CAS200 that used this technology.

[Plasmid]

Looking to see if anyone has taken out the convex lens in the lamp housing. Theres a large spring that sits behind it (not sure why). The lens are held in place by a groove , however they can be carefully rotated along one of the axis ( convex facing out) and cleaned that way, although not the most efficient way.

[apochronaut]

Looking to see if anyone has taken out the convex lens in the lamp housing. Theres a large spring that sits behind it (not sure why). The lens are held in place by a groove , however they can be carefully rotated along one of the axis ( convex facing out) and cleaned that way, although not the most efficient way.

That is a heat proof lens, subject to considerable expansion and therefore mounted loosely. Hence the spring retainer and easy rotation. A secure mount would likely crack the lens pretty quickly.

[Plasmid]

]

That is a heat proof lens, subject to considerable expansion and therefore mounted loosely. Hence the spring retainer and easy rotation. A secure mount would likely crack the lens pretty quickly.

Ahhhh, makes sense, thank you Phil.

Have you noticed that the stages and condenser carriers varied throughout the years,? even though very similar , the carrier from one does not fit the other. I also noticed that the convex lens that normally sat under the condenser did not swing all the way (clearance) with the larger 400 series stage. The stage limiting screw is quite different as well

[Plasmid]

I was able to adapt the phase contrast kit onto the Diastar, that allows me to have BF, EPI, DF up to 20x and PH up to 40X

The Rotating polarizer part you see on the stage normally screws on the bottom of the condenser, the Polarizer was taken out and oved onto a filter holder that sits on top of the field lens below the condenser, which can be rotated. The 1/4 lambda plate was then moved to the insert that sits inside the condenser, which can also be rotated.
The analyzer sits in a fixed position in the empty space just above the nosepiece.

[apochronaut]

A couple of comments. I have encountered the heavy duty condenser fork on Diastars mostly but one in my possession right now, has the light duty fork. The early literature showed the 1.25 aspheric condenser but later literature showed the .90 achromat for the Diastar and still the 1.25 aspheric for the Microstar IV.

In mounting the 1.25 aspheric in the heavy duty fork with the aux. condenser, I have found that a shim washer located between the aux. condenser body and the condenser body is required, so that the aux. condenser can swing in and out without obstruction from the condenser fork. With that shim, sll works well. I don't know how that matches the original condenser set ups. W.A. Butter would know. It is possible that the two forks were designed to be compatible with the two different condensers : the # 1970 1.25 abbe aspheric in it's integrated mount and the # 1201 .90 achromat aplanat in the older customizable mount, which can also receive the # 1973 1.4 achromat aplanat, needed for the 100X 1.30 planfluor and DIC applications.

There was a third stage I only see on the Diastar. It has a thumbscrew just under the left side of the stage , that upon release allows a 90° rotation. Nice perk on that one. Diastars are great, especially with the original planfluor or the Reichert Austria planapos in them.