MicrobeHunter.com Microscopy Forum

I previously wrote up a solution for this which involves a segment of pvc pipe and a 38mm to m42 adapter, but this one is actually cheaper and looks less like a length of PVC pipe with a 38mm to m42 adapter.
The Olympus Photomicro L is a beautiful adapter which grabs onto the 38mm dovetail of an Olympus BH2 series microscope and acts as a spacer to put an SLR camera the proper distance above an NFK series photo eyepiece. They're beautifully designed (the nicest looking camera adapter you're likely to find from any brand) but kind of rare and usually expensive. Diagnostic Instruments made the PA10-a adapter which works perfectly but is also sort of rare and often expensive when it comes up. So alternatives are called for.

Long story short, Olympus made a lot of camera adapters, including the PM10a (and other similar ones) which included a shutter mechanism and beamsplitter with eyepiece to preview the image. They connected to a specialized microscope camera, and are often available inexpensively since these are obsolete. The bottom has a nice clamp for the BH2 photo dovetail, and the insides can be safely ripped out since they're no longer necessary (though it feels a bit bad to do) allowing light to pass through.
The microscope camera has a shorter flange focal distance than a dslr, so you can't directly adapt onto the camera mount. You can, however, unscrew the mount, revealing a 67mm thread. With a 67mm to m42 adapter (ie https://www.amazon.com/…/B0…/ref=cm_sw_ ... KEbTA3FEVD), a medium m42 spacer (the standard ones you get on eBay as part of a three pack for very little) and an eos to m42 adapter you have a fully functional and parfocal adapter for a fraction of the typical price. It's kind of bulky though and will sit cockeyed on your scope since the orientation of the camera is co trolled by how the threads happen to line up.

Is that a serial RS232 port on the adapter? What does it do?

Once it connected a controller that would operate the shutter. Now it plugs the hole so light won't get in.

Now it plugs the hole so light won't get in.

:)

Hi. I am new here and have read this in an attempt to figure out the best, most economical means of capturing good quality live video that I can stream for a class now and work down the road. I own a BH2 but I don't have a ton of money for a camera set up with expensive adapters etc. I really like Scarodactyl's approach with the PM-10A as I can find these very reasonably. I don't currently have a camera and am not sure if I should purchase a microscope camera such as an Amscope model or something else. I do need to connect to my computer in real time for live streaming. Any suggestions would be welcome and, if you would be so kind, what particular adapters I would need to get from the PM-10 to the recommended camera.

Thank you in advance. Kind regards

A DSLR can give you better results than one of these amscope cameras most of the time (and there isn't really a good way to hook up a small-sensor microscope camera to a BH2 series microscope anyway). A Canon T6 is not super expensive used (around 200ish bucks, they were going down pre-pandemic but everyone wanted to get back into photography during the pandemic so prices went back up a bit), has 18mp resolution and can be directly connected to a screen via hdmi. I am not 100% sure of the best way to stream live video but I believe it's possible with canon's newer webcam tools. A t6 has a crop sensor so the image size with a 2.5x nfk photo eyepiece will be a bit mismatched, and you'll only capture the very center of the image. This isn't a big deal though, and it's something you'll face with small-sensor microscope cameras as well.

Unfortunately the 67mm to m42 adapter that I linked from Amazon has long sold out and I haven't found another source the past couple times I've looked. You'd need to get a couple of step up filters to adapt it to m42, something like a 67-62 plus a 62-42. To get perfect parfocality (since the medium spacer would no longer be weirdly perfect as it was with the original step up adapter) you'd probably want to get an M42 helicoid like this one in addition to the spacer set so you could set the length very precisely.

I've just epoxied EF adapter to the original adapter, its perfectly parfocal:

That's interesting--I couldn't get a parfocal image by handholding my camera above mine, but they likely offered different adapters to attach to the top there. Definitely worth checking before messing with other adapters.

Thank you for the additional help!! I will take a look.
Thanks again

qanunji, pardon my ignorance, but could you please provide additional information to exactly what is the "original adaptor"? Is this the PM-10A adaptor? Do you also have the NFK 2.5 eyepiece in this setup?

Thank you

Hi I would like to bunp this thread because I too am a newbie looking for the cheapest way to connect my Sony A7 to an Oly SZH10...... I have most of the kit mentioned including the camera EP, and mount for it, but I am missing something. since this is Eyepiece projection as long as the eyepiece focuses it shouldn't matter as to the distance to the camera should it? Further distance just means larger image scale?

The eyepiece is optimized for one particular distance. If you move the camera higher or lower the kmage will go out of focus, and if you then refocus the objective or move the eyepiece up to compensate this will degrade image quality (a test of raising the 2.5x nfk just a bit to act like a 1.67x gave surprisingly bad results). Best to use it as specced or very close.

How about this? It's an emulation of the Photomicro adapter that connects from the 38 mm dovetail of the BH2 head directly to a Canon EOS mount or Nikon F-mount DSLR. You can find it on eBay.


It's considerably cheaper than the original. It's made of anodized aluminium and I have had no problems using it either mechanically or optically. With an NFK 2.5x photo eyepiece it projects the correct-sized image on a full-frame 35mm sensor and it is roughly parfocal (you just have to tweak the focus a little bit while looking through the camera viewfinder - some may have an issue but I'm not too picky).

If it's the same seller, he also has adapters for other sensor sizes. To connect an aps-c camera to the side photo port of my IMT2, which uses the same 38mm dovetail connector, I first tested the concept with a NFK 2.5x and a cobbled-together tube then found this practically made-to-order adapter/tube on Ebay:

https://www.ebay.com/itm/264259223954

If you scroll down the Ebay ad, you will see various photos of the actual adapter. It's shorter than Microcosmos' adapter, as it's meant for aps-c sensor cameras--you just use it with the appropriate T2 adapter for the camera. I don't know if it's the same seller as for the full-frame tube above, but it's good quality and so far works well. Not a big deal that it's not quite parfocal with the eyepieces, as I adjust fine focus on screen. The dovetail-connector part also screws off of the tube, so could be used for other projects.

Newhoper's adapters should be perfectly fine too, as long as the spacing is correct. The linked one looks pretty short but it's hard to say if it'd be enough to cause problems (maybe moreso at low mags).
The advantage of the Pm10a is that it is occasionally dirt cheap. For the last one I set up I 3d printed a thread adapter for the top which worked fine but I'd like to redesign it to be shorter.

Scarodactyl wrote: ↑

Mon Apr 13, 2020 6:30 am

The microscope camera has a shorter flange focal distance than a dslr, so you can't directly adapt onto the camera mount. You can, however, unscrew the mount, revealing a 67mm thread. With a 67mm to m42 adapter (ie https://www.amazon.com/…/B0…/ref=cm_sw_ ... KEbTA3FEVD), a medium m42 spacer (the standard ones you get on eBay as part of a three pack for very little) and an eos to m42 adapter you have a fully functional and parfocal adapter for a fraction of the typical price. It's kind of bulky though and will sit cockeyed on your scope since the orientation of the camera is co trolled by how the threads happen to line up.

The adapters I found are 67-52 mm and 52mm to M42.
Could you perhaps tell me what the dimension is of the height from the top surface of the PM-10-A to the flange of your camera so I would know what to shoot for.

Sorry I haven't had this microscope for a couple of years now.

In case this is not something already well known, but the photomicro adapter H seems designed to be mounted on the PM10 to proovide OM-mount.
Then an Om to EF could be used.

Not sure what your camera sensor size is but I used a U-PMTVC (has a screw for adjustability to achieve parfocality) and a C mount to 4/3 micro adapter. In total, it cost me about $50 for the PMTVC and $5 for the adapter. You’ll need an NFK 2.5x or 3.3x which are cheap. Ideal is 1.67x but that’s like $500+ and rare. Hope this helps!