Considering making an inf. frankenscope, would like epi options, have some objectives, thoughts?

[lamor]

Hi all!

I have a bunch of objectives now, some OK and purchased for a pittance, since I got into photomacrography using my camera and finite/infinite+tube objectives mounted to my camera, but not on a microscope.

I now find myself with a set of OKish olympus objectives (some UIS1 and one PlanC 40x 0.46 NA) originally for the cx22 in the full mag range, and I'm curious about piecing together a microscope. I've mostly, before photography, done fungal microscopy and still enjoy doing that, but I have a dirt cheap finite amscope (not that that is the main limiting factor). After acquiring these objectives as kind of an add on to another item I wanted, I was considering options for making a frankenscope with them that might satisfy some of the microscopy-focused things I'd like to explore, but perhaps with some flexibility to take the head off and do some photography too.

Primer: I have ample 3d printing experience modeling and printing adapters for other things, and have done a lot with 3d printing for the photomacro through objectives stuff. I can also CNC things, have no issue tinkering. I started down the trek of trying to potentially acquire a vertical illuminator after happening upon a few infinite nikon BD DIC objectives like the ones pictured on this weird metallurgical microscope: https://www.martinmicroscope.com/produc ... -dic-used/ . The idea back then was perhaps fiddling and seeing if I could get some sort of halfway working reflected DIC effects using a surplus normarski prism through an illuminator, but also I have some objectives that are just useful for EPI, so it's something that I wanted to explore. I will try to shelve the DIC subject itself since I wanted to make another post about that, and I'm still reading through past posts, but something to keep in mind about my original thought down this line. Just epi would be fun to play with.

Now that I have these regular olympus inf. objectives, I'm wondering about instead of acquiring piecemeal things like a vertical illuminator just for photog, if I can build a cheap-ish scope and modify on parts like an illuminator and get some more regular microscopy use out of all of the equipment since I think even an introductory set of olympus inf objectives may be slightly nicer than the finite amscope, even for the potential of playing with polarized light and having infinity space available to me. This is kind of a platform for learning, since I already have been learning a TON by experimenting and looking things up.


Sooo, I was considering something like: a cheap CX22 frame or even some of the cheapish BX frames that come up to clobber on the olympus objectives I have, plus an illuminator if I find one for an OK price. I understand the need for a tube lens in an infinity corrected system and have some things that are suitable as tube lenses from photography use, but I'm not sure how specific or picky the "head" assembly on the CX/BX frames is when I plan to use it for regular microscope use instaed, or if I could get myself into a pickle where I buy a frame but the binocular head with the tube + relay lenses isn't compatible with the frame if I eventually find one or it's prohibitively expensive. Basically, trying not to work myself into a corner not knowing exactly what models are around and what's workable or feasible, or if I should watch out for certain condensers/etc.

In general, any advice appreciated on:

1. is getting a used CX/BX frame and piecing something together with an epi illum and binocular head an OK idea with some existing objectives I have? Would like potential flexibility for polarization, maaaybe reflected DIC experimenting (and failing I'd guess) with those BD DIC objectives I have, other modalities, etc but it would be nice to have a slightly nicer regular microscopy microscope

2. Any illuminator advice, in general? Seems like things with filter cubes and the like are a bit more expensive. can't figure out models of what goes to what, though I'm happy to adapt anything with printing or machining as it's easy enough. Just don't wanna end up with an unworkable mess

3. I'm finding it hard to find general things like which microscope these BD DIC objectives were originally used on, what different microscopes are compatible with what even as far as illuminators, etc. How do people research this, since it seems hard to just find straight answers or know which models of microscope base might be suitable for a frankenscope? It seems like lots of space near the stage would be helpful. I had considered things like searching for a used CX frame, microphot (a lil spendy), or even some optiphots but even there it seems like some used to be finite and some used to be inf. It's hard to even find what a specific CX model has that another doesn't, sometimes.

Any thoughts are great! Thanks.

[PeteM]

It sounds like you want to have both an episcopic and brightfield scope at a bargain price.

One way to go:

1) Get a complete but affordable epi microscope stand, intermediate illuminator, nosepiece, and BD objectives. Either an Olympus BHM, maybe a BHT or BHS plus an epi illuminator, or a Nikon Optiphot could fit the bill - make sure to get one that has bottom illumination and a condenser AND interchangeable nosepieces. You might expect to spend around $400-500 -- they often go cheap here in the Bay Area. Sell or swap any incompatible epi objectives you might already have.

There are multiple generations of epi optics such as Nikon finite 210mm, Olympus f=180 infinite that used regular Olympus finite heads, etc. All can provide good images - just get something complete and compatible.

2) Get a brightfield turret for your Olympus infinity objectives plus an Olympus BX infinity head. That might be another $300-$500. Make a 3D-printed part or machine one from something like a polarizing intermediate to match the stand's (BHM? BHT? Optiphot? Or??) dovetail to your head. That part will sit in "infinity space" and still allow full function.

[lamor]

It sounds like you want to have both an episcopic and brightfield scope at a bargain price.

One way to go:

1) Get a complete but affordable epi microscope stand, intermediate illuminator, nosepiece, and BD objectives. Either an Olympus BHM, maybe a BHT or BHS plus an epi illuminator, or a Nikon Optiphot could fit the bill - make sure to get one that has bottom illumination and a condenser AND interchangeable nosepieces. You might expect to spend around $400-500 -- they often go cheap here in the Bay Area. Sell or swap any incompatible epi objectives you might already have.

There are multiple generations of epi optics such as Nikon finite 210mm, Olympus f=180 infinite that used regular Olympus finite heads, etc. All can provide good images - just get something complete and compatible.

2) Get a brightfield turret for your Olympus infinity objectives plus an Olympus BX infinity head. That might be another $300-$500. Make a 3D-printed part or machine one from something like a polarizing intermediate to match the stand's (BHM? BHT? Optiphot? Or??) dovetail to your head. That part will sit in "infinity space" and still allow full function.

Thank you, Pete, the example directions are elucidating. Yes, I'd say that motivation summary is correct. Except that I'm mostly looking for an experimentation platform to learn learn on for cheap-ish with the hopeful benefit of slightly improved performance than the fin amscope owed to köhler and infinite optics for bright field.

So, #2 felt a bit more appealing in a way. I'd like to play with epi and try different objectives out, even if they're not parfocal and space might get a bit tight, since I won't be relying on a perfectly set up config while playing aside from the default bright field config.

To that end, I impulse purchased a broken bx40 for pretty much nothing which includes the non-dovetail swap turret, frame, condenser, light iris etc, and stage carrier. From reading the service manual, it doesn't seem bad to repair or retrofit. I imagine I may run into issues with space for objectives that are parfocal at 60mm from what I see online, but I guess I'll see. I also realized the bx accessories are spendy spendy, but tentatively I was considering temporarily running things just through a tube lens like the raynox dcr-150 despite the f=208 vs Olympus f=180 spec using my camera to test. Can't recall how tolerant that config was to large infinity space separation. But for now, I have almost nothing invested so I can see if I want to continue or not. Don't mind investing in some things if things are fruitful. Seemed like there was a fixed to dovetail nosepiece adapter made by Olympus for these as well thwt I imagine I could print if I needed a different turret. Was just thinking of printing a tiny adapter for objective threads that are different for the current turret since I have had good luck printing microscope threads.

Two things I found a bit confusing:

1. I wasn't sure if there'd be an issue just using a temporary f=208 raynox like I use with my objectives in photo macrograpgy config (aside from mag change) to get things booted up and test objectives. Seemed like infinity space separation wasn't an issue if I added epi, but also not sure of limitations. Only note I saw in service manual was the ergonomic tilting u-tbi vignettes with epi or extra infinite space for some reason. [Edited]: removed my confusion at the trinoc head already including the tube lens, it seems like it would My only remaining question is if the superwide trinocular head would be fine to use with some temporary FN22 eyepieces instead of FN26.5, at the cost of the missing field size, since I think the tube lens in the head may be slightly better for photography and I don't care much about the eyepiece view or could upgrade later.

2. Obviously the bx dovetail illuminators are pretty spendy. Things like the u-kmas seemed better, but didn't have aperture or field stops, which I'm not sure if they'd present an issue. Earlier on I had considered just a cheapo old Nikon epi tube with aperture and field stops but not sure if there is an issue there aside from disassembly and reconfiguring the dovetails via a printed adapter.

Any direction thoughts welcome, thanks for the food for thought.

[Garz]

i am interested in this

in particular to understand what type of photography lens i might adapt for use as the tube lens for an Olympus BX infinity system

i have BX scope i am using for microbiology - but the head unit is not in great condition due to poor storage by previous owner - and even used trinocular replacements are typically around £800+

i have access to a lathe for making tubes and adaptors and have a 13MP HDMI camera on the way - so it could be possible to convert the scope to direct to HDMI camera - no head unit for better quality images - and the Tube lens itself is the missing element

would appreciate any input on how i figure out what i need optically in that Tubelens - to suit scope and camera ??

[PeteM]

A relatively easy and affordable way to get a tube lens for an Olympus BX would be to scavenge one from a broken BX (U-BI30) binocular head. The eye tubes fairly commonly break off during a spill, leaving a tube lens and dovetail behind. With patience and eBay luck, you might find the parts around $100-200.

My approach (for those with access to a metal lathe) has been:
- remove the outer cover of the broken binocular head
- bandsaw around the dovetail to get a roughly circular seating area
- clamp the dovetail in a "JFK" 5C collet and turn it down, leaving a mounting area for the ID of a tube and seating area beyond the dovetail
- use an m42 extension tube epoxied above the tube lens as a start
- use standard m42 tubes and camera adapters to mount the camera of our choice

You can go direct from the tube lens to about 1" to MFT or APS-C size. You'll want to accommodate a relay lens for a full-frame sensor.

If you don't have access to a lathe, the tube lens could be removed and placed in a 3D-printed adapter. I'd use extension tubes as above for height adjustments and camera adapters. And, of course, there's the Olympus U-TLU adapter and Olympus OEM parts for C-mount and full-frame cameras.

[Scarodactyl]

If you aren't using a whole head an Olympus original tube lens is not really necessary. You will get good results from any number of well corrected third party lenses with an appropriate focal length (around 180), possibly superior results to the normal non-widefield Olympus tube lens. Something like a Kenko no 5 achromatic closeup lens (200mm) would be a cheap option with a good chance of success.

[Garz]

thanks for the input both

Pete - i have looked for a banged up binocular head - but they are not so common - nothing in the last 6 months - that's why i was considering other approaches

Scarodactyl - i was hoping the geometry of the tube lens might be such that other sources might work
the Kenko offering looks promising

i see the spec for the tube lens in the Olympus U-TLU is here - along with some indication of how a tube lens should be used - distances etc - which is helpful

https://www.olympus-lifescience.com/en/ ... ontent6649

it is indeed 180mm focal length and 1x magnification

the camera i have on the way is a long way from a full frame sensor -(i may go for a full frame DSLR at some point if i find it necessary).
but i am mainly using 400 to 1000x magnification - so resolution limit is likely below 5mp - so i hope the 13mp sensor in the small camera - even though small will be sufficient to not be the limiting factor
the spec of the sensor is given as
Optical format:1/3"
Pixel size:2.8um*2.8um

what i am curious about now and hoping you can educate me a little in is how the tube lens magnification interacts with the camera position, image size and focus

ie was the kenko close up lens with a magnification of 5x chosen to best suit a full frame sensor -
and will i therefore need a lower magnification if i am using a 1/3" sensor ??
( i am just trying to understand how the elements interact)

apologies to the OP - it seemed related - but i will start another thread if its too far off topic / not of interest to you

[lamor]

A relatively easy and affordable way to get a tube lens for an Olympus BX would be to scavenge one from a broken BX (U-BI30) binocular head. The eye tubes fairly commonly break off during a spill, leaving a tube lens and dovetail behind. With patience and eBay luck, you might find the parts around $100-200.

My approach (for those with access to a metal lathe) has been:
- remove the outer cover of the broken binocular head
- bandsaw around the dovetail to get a roughly circular seating area
- clamp the dovetail in a "JFK" 5C collet and turn it down, leaving a mounting area for the ID of a tube and seating area beyond the dovetail
- use an m42 extension tube epoxied above the tube lens as a start
- use standard m42 tubes and camera adapters to mount the camera of our choice

You can go direct from the tube lens to about 1" to MFT or APS-C size. You'll want to accommodate a relay lens for a full-frame sensor.

If you don't have access to a lathe, the tube lens could be removed and placed in a 3D-printed adapter. I'd use extension tubes as above for height adjustments and camera adapters. And, of course, there's the Olympus U-TLU adapter and Olympus OEM parts for C-mount and full-frame cameras.

Oops, forgot to reply to this thread for a few days as I was off to the races on some 3d printing while shopping around.

Temporarily while hunting for a swtr or alternate trinocular, I opted to adapt my raynox dcr-150 close up lens from my photomacro quick swap printed adapter to work on the bx dovetail. Standard m42 end so I screwed on an m42 to Sony e adapter. Sorry for the crap photos.

IMG_20240429_171657_copy_422x1126.jpg (37.53 KiB) Viewed 125 times

This was version 3 that has space inside for telescoping elements that are flocked for stray light, a quick test after having made a helicoid screwing type here with the raynox as a tube lens holder pictured on the far right:

IMG_20240426_165904_copy_600x800.jpg (118.99 KiB) Viewed 125 times

Graduated in mm on the side for being able to use different tube lengths requiring different distances for infinity focus, or some adjustments.

A few quick snaps showed promising apsc coverage but I've been busy with some other tasks to work through things more thoroughly.

For now, I have a semi busted American optical inf binocular head which should be neutral in corrections that I might try to use to bide my time.

Sarcodactyl kindly answered a bunch of questions on a different forum to help me get a sense of some direction / options. I may consider a non-olympus inf. trinocular instead since the only reasonable Olympus superwide trinoc online right now seems to have some spotted fungus on one prism (not sure how miserable that would be to clean). But the ultimate dream / goal is a nice trinocular head and a nice scope, so maybe more waiting for me. This should allow me to hunt around and use the camera with HDMI out to a monitor, albeit with different magnification due to the different focal length tube lens.

Happy to share a model once I've refined things a bit or send someone prints if they need it, once refined and if it's a workable solution.

For now, my next point of frustration is trying to see what epi illuminator I might be able to adapt on that may be better/cheaper than going with the basic u-kmas (maybe an older Nikon with field/aperture stops?). Not sure if I'd get into a situation where the max field / aperture stop is smaller than the BD ring on some of the objectives I wanna play with. I wish Olympus did publish figures on intermediate space and vignetting, since all I could find in the bx40 manual was that the ergo tbi head vignettes when used with intermediate devices.

thanks for the input both

Pete - i have looked for a banged up binocular head - but they are not so common - nothing in the last 6 months - that's why i was considering other approaches

Scarodactyl - i was hoping the geometry of the tube lens might be such that other sources might work
the Kenko offering looks promising

i see the spec for the tube lens in the Olympus U-TLU is here - along with some indication of how a tube lens should be used - distances etc - which is helpful

https://www.olympus-lifescience.com/en/ ... ontent6649

it is indeed 180mm focal length and 1x magnification

the camera i have on the way is a long way from a full frame sensor -(i may go for a full frame DSLR at some point if i find it necessary).
but i am mainly using 400 to 1000x magnification - so resolution limit is likely below 5mp - so i hope the 13mp sensor in the small camera - even though small will be sufficient to not be the limiting factor
the spec of the sensor is given as
Optical format:1/3"
Pixel size:2.8um*2.8um

what i am curious about now and hoping you can educate me a little in is how the tube lens magnification interacts with the camera position, image size and focus

ie was the kenko close up lens with a magnification of 5x chosen to best suit a full frame sensor -
and will i therefore need a lower magnification if i am using a 1/3" sensor ??
( i am just trying to understand how the elements interact)

apologies to the OP - it seemed related - but i will start another thread if its too far off topic / not of interest to you

So, the magnification when used as an add on lens in front of a regular camera lens isn't the important aspect or the resulting magnification you'll get when used as a tube lens, focused to infinity (with the tube lens X distance from the sensor plane). For example, the raynox dcr-250 or dcr-150 close up adapters are like 125mm focal length and 206mm focal length or something like that, respectively. When you use a tube lens of, say, fl 200mm when the objectives on these Olympus scopes were designed with fl180 in mind, you'll get magnification in the ratio of 200/180 or about 1.1x on sensor of what any stock Olympus objectives state their magnification is because you're using a different focal length tube lens. Use a fl 100 lens and you'd get about half the magnification stated on the objective, on sensor image size. Remember, your oculars have like 10x or whatever magnification in addition to the magnification imposed by the objective + tube lens system. So if your 50x Olympus objective + f180 (stock) tube lens results in an intermediate image magnified at 50x as expected, your 10x binocular head brings it up to the 500x you're stating. When we're considering using a camera on a tube lens + objective system we're calculating what the magnification at the sensor plane of an object is and how large it will appear on your sensor in comparison to the real life size. You can get empty magnification by blowing the image up, or using 15x oculars, etc. another general thing to consider is that on the object side your resolution ans depth of field will be determined by the numerical aperture of the given objective. On the sensor side, the resolving power will be determined by the pixel pitch and magnification (and wavelength of light used, but you can approximate using green light at 550nm).

You won't have to cover a very large sensor with what you stated, though, so you may not have to worry about a large, nice tube lens just to take some photos.

At least that's my understanding this far in this short photomacrography journey. Anyone feel free to correct anything that's misconstrued. No worries on my end re: adding on with questions.