First Microscope: Inverted or immersible lens?

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n3u120
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First Microscope: Inverted or immersible lens?

#1 Post by n3u120 » Sat Mar 23, 2019 4:20 pm

I have never owned my own microscope, but I am not new to microscopy. I have used, inverted, upright, and spinning disk confocal microscopes. I’m finally looking to buy my own, but obviously on a lower budget than work. Admittedly, I’m also not super knowledgeable on many details of microscopy.

I’m in a personal debate on whether I buy an inverted or an upright microscope with an immersible 40x objective. I need something old, but that I can upgrade to DIC and fluorescence as the budget and wife allows.

AO Biostar 1820: I have seen awesome deals, but the information and parts seem to be hard to find. It also doesn’t allow for DIC or fluorescence upgrades.

Nikon Diaphot is next in line along with the Olympus IMT-2. These are more expensive, but seemingly more upgradeable with more information.

Uprights seem cheaper in general though. Found awesome deal on Hund Wetzler H500 with fluorescence, but can’t find much info . I would need an immersible objective which are spendy, but could use a low quality one for my purposes. Or if I wanted to look at fine details of a rock. Inverted seems to have the edge on this, but I won’t be using flasks, test tubes, large rocks etc. Maybe 1-1.5cm tall items?

If I could make an upright as versatile I would prefer it. It seems like they are more flexible for objective choice, parts are easier to find, and they are more budget friendly. That or do I convince the wife I need both ;) the latter is unlikely to happen!

Thanks for any help, I see many of you own some of these!

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Re: First Microscope: Inverted or immersible lens?

#2 Post by PeteM » Sat Mar 23, 2019 5:52 pm

I'd suggest you buy the best microscope you can for your current budget and worry about flourescence and DIC later.

Particularly for DIC, the eventual cost of a setup will dwarf your initial purchase. And, better not to constrain your search to what you have -- you might well save far more by lucking into a modestly priced unit of some other brand. Same logic applies to fluorescence as well, but with perhaps less $$$ at stake.

Why do you want/need a (water?) immersible 40x objective? That, alone, may cost as much as a good microscope stand. Finding one could decide which microscope it comes along with. For example, you can find Lomo water immersion objectives affordably -- and they'll want an upright stand capable of focusing close. Maybe something like an Olympus CH or, of course, a short barrel Lomo.

To add, inverted microscopes while using things like petri dishes don't really use "water immersion" objectives. The subjects may be in water, but the objective itself doesn't dip into water and thus doesn't need to be sealed and corrected for water immersion.

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Re: First Microscope: Inverted or immersible lens?

#3 Post by Hobbyst46 » Sat Mar 23, 2019 6:52 pm

Since you are experienced with advanced illumination microscopy techniques and know what can be done with them, I think maybe you might want to search for a DIC-fluorescence microscope right from beginning, if budget allows it. Neither accessories are commonplace and inexpensive if separately bought. Especially talking "old" microscopes.

In my opinion, inverted microscopes are advantageous when access from above the specimen is required. Or when the specimen is held within a petri dish or a multi-well plate.

Here is a listed upright fluorescence microscope that might be of interest:
https://www.ebay.com/itm/AMERICAN-OPTIC ... 0005.m1851
The scope comes with an Exa film camera (I think), but the point is that it is trinocular.
Because excellent information about AO microscopes is available from experts on this forum.

I believe you already know, that epi-fluorescence accessories have been vastly improved along several decades. On 1980s-1990s Zeiss microscopes, for example (Axioplan, etc), fluorescence was already excellent, not much worse than on modern instruments (I am not talking confocal here). On 1960s-1970s microscopes, for example Reichert, Olympus, fluorescence was less convenient to use and less sensitive than on modern scopes. This age difference is more noticable for fluorescence than for other modes (phase contrast, DIC etc). Modern improvements for fluorescence cover illumination sources, power supplies, filter cubes and, of course, cameras. In other words, I would not expect a 50-70 years old fluorescence optics to perform as well as the research-grade microscopes with which you are familiar.

On the other hand, LED excitation sources are available now, they did not exist a few decades back...And modern cameras are very sensitive.

Hope this helps. Good luck!

Edit: Here is a much more expensive, Olympus inverted fluorescence scope, that includes both illuminators (BF and FL).
https://www.ebay.com/itm/OLYMPUS-IMT-2- ... SwlLdccH5p
Where one can make an offer; the seller does not accept returns.

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Re: First Microscope: Inverted or immersible lens?

#4 Post by zzffnn » Sun Mar 24, 2019 12:39 am

Welcome to the forum!

Unless your wife is fine with a $3000 budget fot a complete DIC scope (in which case I recommend PZO or Zeiss, if you can find a Zeiss one without delamination), you can start with any brand.

It would not hurt though, if you start with a PZO or Zeiss frame. Just know that PZO DIC is not easily compatible with Zeiss DIC. With most non-DIC illumination/contrast methods though, you can modify things around to mix some parts from different brands. Mixing DIC parts is possible too, but in most cases they don't work (and you lose money).

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Re: First Microscope: Inverted or immersible lens?

#5 Post by n3u120 » Sun Mar 24, 2019 4:08 am

Thank you all for the input! I would only need the immersion if I bought an upright as you definitely know. It would be an inverted scope, or an upright + an immersion. My thought is to buy the best microscope I can for my current budget and add-on to it every couple months, knowing that the some add-ons will cost close to what I paid for the scope. I haven't looked into Lomo - looks like there are a lot parts available for it so it is worth looking into.

For an upright, the need for an immersion lens would be to patch-clamp cells in a 1-1.5cm deep perfusion stage. I oversimplified by saying petri dish. I would build out a custom stage to flow solution over the sample and mount micromanipulators, flow lines, etc. For a 40x, even with a long working distance, the risk of the solution making a meniscus and hitting the lens of an upright is really high. I came across those Lomo's on eBay and they would work. I won't ever have the budget for a new name brand 40x. I wouldn't use it for pictures, I just need to see a cell and a pipette tip. One consideration was, as you eluded to, an upright would have a lot more flexibility for objective choice.

My biggest hurdle is that I am scared the inverted will be harder to find parts and objectives for. It is ideal, but I could make an upright work very happily if I can get a long working distance.

The fluorescence would be the first add-on. DIC setup is less important, but I'd like the ability to eventually. At work I use a Zeiss Axioskop 2 and Olympus BX51, but that is definitely out of budget. That second ebay link is perfect! But the budget does not allow for it right now. Just under half that is reasonable. The first one for the American Optical 2070 is well within budget.

I was also looking at these:

IMT-2:
https://www.ebay.com/itm/Olympus-IMT-2- ... ctupt=true

Diaphot:
https://www.ebay.com/itm/Nikon-Diaphot- ... SwkNFcbf-t

https://www.ebay.com/itm/Nikon-Diaphot- ... SwzX1bT~Ms

Upright Hund
https://www.ebay.com/itm/Hund-Wetzlar-H ... ctupt=true

Plus the Amirican Optical scope posted in Hobbyist46 post.

Thanks for all the info on the grades of fluorescence. I know the tech has come far, but I'm young and have been spoiled. I haven't looked through an older fluorescent scope nor cared to read about it until lately.

The Nikon and Olympus above can be upgraded to DIC. I'm not brand loyal and it doesn't need to be 'name brand' . I haven't looked at Zeiss because their rep put a bitter taste in my mouth. On my Axiskop 2 with DIC I needed a new immersion objective, he said they changed their objective design so I would need to buy a new DIC microscope. I called Olympus and they sent a rep out that fitted my Zeiss with an Olympus objective and let me demo it for two weeks. It is a wonderful scope and I should probably get over my Zeiss rage. I haven't heard of PZO so I'll do some research on them!

My biggest hurdle is that I am scared the inverted will be harder to find parts and objectives for. It is ideal, but I could make an upright work very happily if I can get a long working distance.

Welp, that all helped a lot so thank you again. Looks like a bit more research to do and I just need to get it over with and make a purchase.

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Re: First Microscope: Inverted or immersible lens?

#6 Post by PeteM » Sun Mar 24, 2019 4:49 am

It sounds like you're really going to want the top side access of an inverted scope.

If fluorescence is in your near future, I'd suggest buying something like an IMT-2 (or Nikon inverted) complete with that to begin. A complete scope is almost always cheaper than adding on things bit by bit -- and will also save time in the looking.

If fluorescence isn't so important, than something like an Olympus CK-2 might do the job at lower cost -- maybe even under $500. They are pretty bullet proof and will hold their value if you end up upgrading. Just get the one with a fine focus, since even 40x is pretty fiddly in an inverted scope. Olympus LB long working distance objectives are fairly commonly available -- though I'm not so sure about ones with good fluorescence transmission deep into UV ranges.

Would phase contrast help you see well enough for manipulation? Or is image quality paramount?? Lot easier to find affordable inverted phase contrast than DIC.

On edit: just took a quick look at your links. The Nikons appear to be without objectives. The Olympus is missing the 40x you want -- a proper LWD one with a correction collar might add another $250-300?

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Re: First Microscope: Inverted or immersible lens?

#7 Post by n3u120 » Sun Mar 24, 2019 5:46 am

Honestly, I haven’t used phase contrast much and DIC level quality isn’t necessary. Thanks for the point on resale value. My real goal now is to get something fun to play with and setup some cool rudimentary experiments on. I’ve never gotten to look at whatever I want on a scope, like microbes, a leaf, blood cells. I have never looked at pond scum. Neurons of the pond snail are huge and I could easily record electrical currents from them (100um wide). I want to create a type 2 daibetes model from them and see if there neurons are resistant to glucose. I want to genetically engineer my own yeast for brewing beer and image it.

I could save up more and buy a ‘complete scope’ but it would be another six month to one year wait. This has been super helpful and helped bring me back to earth a bit. I’m spoiled at work, but the closest thing to a scope I’ve personally owned is a scratched up jewelers loop. Pretty sad actually.

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Re: First Microscope: Inverted or immersible lens?

#8 Post by n3u120 » Sun Mar 24, 2019 5:51 am

PeteM wrote:
On edit: just took a quick look at your links. The Nikons appear to be without objectives. The Olympus is missing the 40x you want -- a proper LWD one with a correction collar might add another $250-300?
Thanks for the catch on the 40x. If I bid on it and didn’t have to compete with someone then I could afford $250-300 for the objective. I’m really attracted to that scope.

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Re: First Microscope: Inverted or immersible lens?

#9 Post by MicroBob » Sun Mar 24, 2019 7:03 am

Hi,
I think your new approach is better than the first one. Top grade accessories cost real money and it is good to gain some experience with an own used microscope before deciding the direction of such an expensive approach.

When it comes to manikulatin under a 40x objective you might think about a long distance objective. If you find one for acceptable money you could buy a fitting microscope for it.

It is nice to see that you want to enter microscopy as a hobby too and look forward for your reports on your very interesting experiments!

Bob

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Re: First Microscope: Inverted or immersible lens?

#10 Post by Hobbyst46 » Sun Mar 24, 2019 8:17 am

n3u120 wrote:Honestly, I haven’t used phase contrast much and DIC level quality isn’t necessary. Thanks for the point on resale value. My real goal now is to get something fun to play with and setup some cool rudimentary experiments on. I’ve never gotten to look at whatever I want on a scope, like microbes, a leaf, blood cells. I have never looked at pond scum. Neurons of the pond snail are huge and I could easily record electrical currents from them (100um wide). I want to create a type 2 daibetes model from them and see if there neurons are resistant to glucose. I want to genetically engineer my own yeast for brewing beer and image it...I’m spoiled at work, but the closest thing to a scope I’ve personally owned is a scratched up jewelers loop...
1. It is great that you described in detail what you want to see and do with the microscope. Helps to define the goal, equipment-wise.
2. Both Axioskp and BX51 are excellent. A local marketing or customer service problem with Zeiss, related to the institute, should not turn you away from Zeiss equipment for this reason alone. The main point is that those two scopes are upright. Since you have now mentioned future experiments on cells, path clamp etc, an inverted scope might be better.
BTW, AFAIK the objectives on modern research scopes are in general not interchangable between brands.
3. Especially if you plan to set up a flow system on the stage, such that the specimen is under continuous flow, microfluidics etc, inverted scopes are much more suitable than upright ones.
4. For inverted scopes, there are petri dishes and multi-well plates that have coverslip bottoms, and allow high magnification viewing without LWD objectives. In contrast to the manufacturer's intentions, these petri dishes can be cleaned and reused.
5. DIC yields detailed morphological information (with reservation) and great artistic effects (wish I could own DIC...). But, for your purpose, it is not a must. Phase contrast, on the other hand, is important.

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Re: First Microscope: Inverted or immersible lens?

#11 Post by Hobbyst46 » Sun Mar 24, 2019 10:13 am

Both Diaphots seem to lack some basic parts - objectives, condenser... so: I would inquire with the seller about it, and about the exact status of the mechanics and optics. It is difficult to verify that the scope is in good condition if such parts are missing. I would also suspect the "dent" on the back side of the arm of the $349 scope was caused by a serious impact/blow that might have damaged the optical alignment of the microscope, that will be difficult to fix. Also it seems that there are no X-Y stage with a slide holder.

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Re: First Microscope: Inverted or immersible lens?

#12 Post by n3u120 » Sun Mar 24, 2019 5:33 pm

Hobbyst46 wrote: 1. It is great that you described in detail what you want to see and do with the microscope. Helps to define the goal, equipment-wise.
2. Both Axioskp and BX51 are excellent. A local marketing or customer service problem with Zeiss, related to the institute, should not turn you away from Zeiss equipment for this reason alone. The main point is that those two scopes are upright. Since you have now mentioned future experiments on cells, path clamp etc, an inverted scope might be better.
BTW, AFAIK the objectives on modern research scopes are in general not interchangable between brands.
3. Especially if you plan to set up a flow system on the stage, such that the specimen is under continuous flow, microfluidics etc, inverted scopes are much more suitable than upright ones.
4. For inverted scopes, there are petri dishes and multi-well plates that have coverslip bottoms, and allow high magnification viewing without LWD objectives. In contrast to the manufacturer's intentions, these petri dishes can be cleaned and reused.
5. DIC yields detailed morphological information (with reservation) and great artistic effects (wish I could own DIC...). But, for your purpose, it is not a must. Phase contrast, on the other hand, is important.
Thanks for such quick replies. I use those uprights at work because I record from 250um thick brain slices, but that won’t be happening in the garage :lol: We throw those multi-well plates away like crazy, I could get an unlimited supply for free. Thanks for pointing out the missing condenser. I’ve officially narrowed it down to an inverted scope with phase contrast, that at least comes with a couple objectives.

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Re: First Microscope: Inverted or immersible lens?

#13 Post by PeteM » Sun Mar 24, 2019 6:02 pm

Where are you located? If near Northern California, I have a German-made Hund Wetzalar inverted scope that I'd sell affordably if you'd be willing to contribute a lesson or two (cool image, explanation of the science behind it) for our "Micronaut" program.

This would not be easily expanded. But, it does come in newish condition with a trinocular head, and phase contrast. It's complete with annuli and Hund 4x-10x-and a 20x phase long working distance objectives plus a 32x on a four lens turret. The trinocular head has Olympus standard (dovetail) camera fittings. Image quality seems on par to Olympus CK-2 era scopes. The highest power phase objective is 32x Leitz Phaco LWD with a matching annulus. Not sure 320x is enough for your purposes, might be pushed to 480x with 15x objectives (numerical aperture is 0.40 so only around 400x intrinsic resolution)?? Also have a spare Biolam 1820, but not sure about the lens and phase complement. Plus some Olympus and other inverted phase objectives not yet married to stands.

The older Olympus IMT scopes are also well built and you might find one complete (phase, 40x, etc.) affordably. Massive scopes -- you wouldn't want to ship one far. The IMT-2 you've found looks the best of the links, but will likely be over $1000 even if no one else bids on it -- once you add a proper 40x LWD objective and ship the scope. And the built-in camera port might not be best for imaging unless you have a full frame DSLR.

If you just want to get started with an inverted scope, trinocular head, 40x, and phase contrast I think you can find something, with a bit of patience, closer to $500. Then, learn what you want, and save up for your ultimate system microscope??

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Re: First Microscope: Inverted or immersible lens?

#14 Post by zzffnn » Mon Mar 25, 2019 6:11 am

The main application of that LOMO water 40x 0.75 objective is dipping and patch clamp.

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Re: First Microscope: Inverted or immersible lens?

#15 Post by apochronaut » Mon Mar 25, 2019 3:20 pm

With regards to fluorescence, DIC, Phase contrast and their application to L.W.D.( inverted microscopy).

In the case of most microscopes, some of these techniques are mutually exclusive, although there have been concerted efforts to make a microscope as universally capable as possible. The biggest hangup to a single system encompassing such a broad array of techniques is the unique spatial requirement an inverted microscope requires for the illuminating/condensing feature. Even the Reichert Univar and Poly, line of universal microscopes failed to incorporate the features of truly L.W.D. microscope into what was probably the most innovative microscope design of certainly the 1970's.
The distance required in order to maintain the stage access typical of an inverted scope plus the specimen carrier dimensions, preclude a restriction on objective choices, even if cover slip bottom dishes are used. I could see however, the possibility that a scope like the Biostar 1820 could be modified to provide close enough proximity of a higher N.A. dry achromat condenser and along with modified sample carriers, allow the possibility of inverted oil immersion plus some more specialized techniques.

PlasDIC, known as a Zeiss technique for DIC on an inverted scope and is limited to about a 40X objective. It was in fact pioneered in the Hungarian Goerz variable slit condenser of the 60's and was additionally marketed for 2 decades prior to Zeiss' involvement with it, by PZO, as a Differential Interference System utilizing the MPI-3 variable slit condenser. Both possess real possibilities to retrofit DIC onto an inverted scope with fairly easily installed components and you can use standard objectives. The PZO system, uses a polarizer in advance of the condenser as well, so it has a possibility of extending the magnification to higher levels with higher N.A.s. All one needs is a slit type condenser, perhaps with polarizer and a DIC prism and analyser behind the objectives. The bane of the DIC systems and the reason for most of the costs; the Nomarski prism carousel, is not needed. The Goerz condenser in it's complete form comes with several slip on collars in order to change the diameter of it's sleeve fit. It will fit into the mount of the AO 214F DF condenser for instance and it comes with it's own DF masks of up to 1.2 N.A. The PZO unit has a larger sleeve but it could be made to fit into existing condenser carriers quite easily too. It has a linear dovetail underneath to accept a rotating polarizer.

Phase is a reality with inverted microscopy, so the possiblity of extending that to a higher magnification, higher resolution system would follow suit with the above adaption of the condenser architecture.

Fluorescence? I don't know really. I can't see why the standard Microstar/Diastar fluorescence unit wouldn't work on a Biostar for instance? It would make for a pretty cumbersome instrument but I could see a Biostar being the basis of a pretty complete inverted system and not just an inverted L.W.D. microscope.

Slit condensing interference contrast has just as much potential when utilized with an upright scope. It seems, that with all the cost associated with most DIC systems, it might be the budget retrofit worth looking into. A chief advantage is that one does not need to take on the cost of buying objectives known to be suited for DIC with the non polarized version. Standard objectives will work.

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Re: First Microscope: Inverted or immersible lens?

#16 Post by n3u120 » Tue Mar 26, 2019 12:42 am

PeteM wrote:Where are you located? If near Northern California, I have a German-made Hund Wetzalar inverted scope that I'd sell affordably if you'd be willing to contribute a lesson or two (cool image, explanation of the science behind it) for our "Micronaut" program.

This would not be easily expanded. But, it does come in newish condition with a trinocular head, and phase contrast. It's complete with annuli and Hund 4x-10x-and a 20x phase long working distance objectives plus a 32x on a four lens turret. The trinocular head has Olympus standard (dovetail) camera fittings. Image quality seems on par to Olympus CK-2 era scopes. The highest power phase objective is 32x Leitz Phaco LWD with a matching annulus. Not sure 320x is enough for your purposes, might be pushed to 480x with 15x objectives (numerical aperture is 0.40 so only around 400x intrinsic resolution)?? Also have a spare Biolam 1820, but not sure about the lens and phase complement. Plus some Olympus and other inverted phase objectives not yet married to stands.

The older Olympus IMT scopes are also well built and you might find one complete (phase, 40x, etc.) affordably. Massive scopes -- you wouldn't want to ship one far. The IMT-2 you've found looks the best of the links, but will likely be over $1000 even if no one else bids on it -- once you add a proper 40x LWD objective and ship the scope. And the built-in camera port might not be best for imaging unless you have a full frame DSLR.

If you just want to get started with an inverted scope, trinocular head, 40x, and phase contrast I think you can find something, with a bit of patience, closer to $500. Then, learn what you want, and save up for your ultimate system microscope??
I'm in northern Oregon so a little far from Santa Cruz, otherwise that Micronaut program sounds like a lot of fun either way, I do lots of science outreach in my area. Sounds like you have a lot of scopes around! For the live cells I would want to manipulate 320x would probably be more than enough. For the equipment I've used, I know so little when it comes to N.A., proper objectives, etc.

I use 400x for 10um neurons with a ~2um pipette tip (I measure tip size as resistance in MOhms, so this is a guess). The smallest I would go at home is 100um snail neurons, so 10x larger cell. To contribute to the cool history in this thread, between 1939-1952 Hodgkin and Huxley performed and characterized the worlds first neuron recordings from the squid since their axons are 0.5-1.5mm in diameter. They setup a dual-mirror system and built most of their equipment at home/in the lab, including a custom oscilloscope. Looks like they used a stereo miscroscope.

This link has some cool pictures of their setup. Things have come a long ways in 80 years! https://apackofneurons.wordpress.com/20 ... xleypart1/

The scope is just the first and most versatile part (and most important aside from an oscilloscope) of my end goal. The day I record an action potential at home is going to be glorious and I'll probably throw a party!

I appreciate all the help and once I win a bid or 'buy it now' or something I'll post updates here. Thank you all!

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Re: First Microscope: Inverted or immersible lens?

#17 Post by PeteM » Tue Mar 26, 2019 2:18 am

Thanks for that bit of neuron potential history.

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Re: First Microscope: Inverted or immersible lens?

#18 Post by Hobbyst46 » Tue Mar 26, 2019 1:25 pm

apochronaut wrote:With regards to fluorescence, DIC, Phase contrast and their application to L.W.D.( inverted microscopy).

In the case of most microscopes, some of these techniques are mutually exclusive, although there have been concerted efforts to make a microscope as universally capable as possible. The biggest hangup to a single system encompassing such a broad array of techniques is the unique spatial requirement an inverted microscope requires for the illuminating/condensing feature. Even the Reichert Univar and Poly, line of universal microscopes failed to incorporate the features of truly L.W.D. microscope into what was probably the most innovative microscope design of certainly the 1970's.
The distance required in order to maintain the stage access typical of an inverted scope plus the specimen carrier dimensions, preclude a restriction on objective choices, even if cover slip bottom dishes are used. I could see however, the possibility that a scope like the Biostar 1820 could be modified to provide close enough proximity of a higher N.A. dry achromat condenser and along with modified sample carriers, allow the possibility of inverted oil immersion plus some more specialized techniques.

PlasDIC, known as a Zeiss technique for DIC on an inverted scope and is limited to about a 40X objective. It was in fact pioneered in the Hungarian Goerz variable slit condenser of the 60's and was additionally marketed for 2 decades prior to Zeiss' involvement with it, by PZO, as a Differential Interference System utilizing the MPI-3 variable slit condenser. Both possess real possibilities to retrofit DIC onto an inverted scope with fairly easily installed components and you can use standard objectives. The PZO system, uses a polarizer in advance of the condenser as well, so it has a possibility of extending the magnification to higher levels with higher N.A.s. All one needs is a slit type condenser, perhaps with polarizer and a DIC prism and analyser behind the objectives. The bane of the DIC systems and the reason for most of the costs; the Nomarski prism carousel, is not needed. The Goerz condenser in it's complete form comes with several slip on collars in order to change the diameter of it's sleeve fit. It will fit into the mount of the AO 214F DF condenser for instance and it comes with it's own DF masks of up to 1.2 N.A. The PZO unit has a larger sleeve but it could be made to fit into existing condenser carriers quite easily too. It has a linear dovetail underneath to accept a rotating polarizer.

Phase is a reality with inverted microscopy, so the possiblity of extending that to a higher magnification, higher resolution system would follow suit with the above adaption of the condenser architecture.

Fluorescence? I don't know really. I can't see why the standard Microstar/Diastar fluorescence unit wouldn't work on a Biostar for instance? It would make for a pretty cumbersome instrument but I could see a Biostar being the basis of a pretty complete inverted system and not just an inverted L.W.D. microscope.

Slit condensing interference contrast has just as much potential when utilized with an upright scope. It seems, that with all the cost associated with most DIC systems, it might be the budget retrofit worth looking into. A chief advantage is that one does not need to take on the cost of buying objectives known to be suited for DIC with the non polarized version. Standard objectives will work.
Apochronaut, thanks for mentioning this plasDIC! I wonder what light source is needed to pass sufficient brightness through the slit, and about the availability of used slit condensers. These details about plasDIC may be beyond the scope of the OP thread, though.

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Re: First Microscope: Inverted or immersible lens?

#19 Post by apochronaut » Tue Mar 26, 2019 2:57 pm

I mention it because the OP is debating between an inverted microscope, which implies L.W.D., therefore ruling out an immersion system or conversely an immersion system, which rules out an inverted microscope, if you read my post carefully. They need not be mutually exclusive and that a universal microscope based on an inverted might be more feasible than one thinks. It could include a slit condenser modulated interference system, S.W.D. phase, M.W.D. phase, L.W.D. phase, vertical fluorescence, DF and B.F. and COL., while allowing table access to the stage for large specimen holders and micromanipulation.

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Re: First Microscope: Inverted or immersible lens?

#20 Post by n3u120 » Tue Mar 26, 2019 3:47 pm

https://www.ebay.com/itm/Olympus-IMT-2- ... ctupt=true

I came across this IMT2 with a low starting bid. I've studied the pics extensively - it looks like I would need a stage plate (there are some on eBay for about $40), possibly new eyepieces, and a 40x Phase contrast objective. Not sure if I need a LWD if I use a coverslip bottom.

From what I can see the low bid is because of the mismatched objectives, no stage plate, no light filters, and possibly non-matching eye pieces. Maybe needs a prism cleaning too?

I messaged the seller. He sent a picture showing that the bulb indeed works, will come with power cord, and all the knobs move very smooth. Also looked at his other 'for sale' items to learn more about the seller and all items seem to have a low starting bid.

The feet are broken so I'm assuming someone tried to lift it by the feet and they snapped. They are plastic and in no way designed to hold that kind of weight. Most of these don't come with the feet.

It is a $350 gamble... but leaves me with enough to drop a few hundred on a good 40x objective, buy a stage plate, MTV-3 adapter for a C-mount camera, and a dirt cheap starter (Aliexpress) video camera.

I understand I'll be spending more on the needed parts than the scope itself (particularly the objective). But it would still be cheaper than buying one of these with all those parts.

n3u120
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Location: United States

Re: First Microscope: Inverted or immersible lens?

#21 Post by n3u120 » Wed Mar 27, 2019 5:56 pm

apochronaut wrote:I mention it because the OP is debating between an inverted microscope, which implies L.W.D., therefore ruling out an immersion system or conversely an immersion system, which rules out an inverted microscope, if you read my post carefully. They need not be mutually exclusive and that a universal microscope based on an inverted might be more feasible than one thinks. It could include a slit condenser modulated interference system, S.W.D. phase, M.W.D. phase, L.W.D. phase, vertical fluorescence, DF and B.F. and COL., while allowing table access to the stage for large specimen holders and micromanipulation.
Welp, I'm in a 'bidding war' on the IMT-2 so I guess I'll know what happens in 21 hours.

From rereading over achronaut's post about PlasDIC, it sounds like you think the AO Biostar could be modded and fitted out? I had been looking at one that is actually being sold close enough for pickup, but I emailed the seller and it only has one objective (10x).

https://www.ebay.com/itm/American-Optic ... SwPPtck8mf

Here is a complete Zeiss Invertoscope D that is located nearby as well. However, I'm unsure if I can attach a camera (maybe to the bottom) or a phase contrast condenser.

https://portland.craigslist.org/wsc/ele ... 82774.html

The search continues, hopefully I get lucky with the IMT-2, but there seems to be three other bidders interested.

PeteM
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Re: First Microscope: Inverted or immersible lens?

#22 Post by PeteM » Wed Mar 27, 2019 7:22 pm

Good luck. There will be others if this one doesn't work out.

n3u120
Posts: 9
Joined: Fri Mar 22, 2019 3:52 pm
Location: United States

Re: First Microscope: Inverted or immersible lens?

#23 Post by n3u120 » Sat Mar 30, 2019 5:20 pm

I won the bid on the Olympus IMT-2! Also bought an objective from a generous forum member and a stage plate. Plan to start a new thread in the appropriate category once all arrives. Thanks again for all the help. Hopefully I’ll be able to give back to this community as time goes on!

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