I recently purchased my first microscope, an Olympus BH-series BHM. I'm currently servicing the focus mechanism, which was frozen with old grease.
I've been thinking about my imaging options; I have a binocular head rather than trinocular, and no eyepieces so far. To my knowledge, this uses 210mm finite optics. I already own a mirrorless camera (Sony NEX-5), for which I have a C-mount and T2 adapter.
Options that occur to me (that don't involve buying a trinocular head) include:
-removing the head, and using adapters to accomplish direct projection. I wouldn't have an eyepiece for observation, though.
-removing the head, using a photo eyepiece. I don't see a particular advantage to this vs the first option*
-using a 23mm eyepiece to C-mount adapter (with a lens). I'm unsure of the relative optical quality I can expect.
-using a prime lens mated to a regular Olympus eyepiece (I have a 28mm and 50mm). This is more optical components, however.
-i don't think I should use an NFK, with its 125mm projection length, supported by the binocular eyepiece tube.
* I'm not 100% sure about resolving power vs pixel size & resolution - I think I saw that 2 pixel diameters per unit of resolving power is appropriate (?) In this case the 10X objective, with its 1.3 micron resolving power, is well suited to the 5 micron pixel pitch of the image sensor, if I'm understanding correctly. If so, a magnifying photo eyepiece wouldn't seem to do much for me.
I'd love to hear thoughts about those or other options and anyone's experiences! Thanks!
Imaging options for a binocular-head Olympus BH
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Re: Imaging options for a binocular-head Olympus BH
Finite Olynous objectives require corrections provided in the eyepiece. Direct projection will not give good results.
Unfortunately I don't know much about the BH era BHM, just the BH2 BHM so I'll defer to others on that.
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Re: Imaging options for a binocular-head Olympus BH
First, welcome!
Second, I do not own a BHM (or indeed any Olympus microscope);
I did strongly consider getting one years ago, but instead got an AO/Reichert epi microscope.
Most finite microscopes of the BHM era and earlier depend on oculars to correct objective aberrations.-removing the head, using a photo eyepiece. I don't see a particular advantage to this vs the first option*
My understanding is that finite Olympus objectives are among those wanting stronger corrections than e.g. Zeiss.
Consequently, one would either want either:
- a matching Olympus projection (photo relay) lens (2x is often mentioned) to the camera sensor
- an afocal arrangement with e.g. regular Olympus 10x eyepiece to an appropriate (40-55mm) camera lens focused near infinity.
http://www.microscopy-uk.org.uk/mag/art ... p-bhm.html
http://www.alanwood.net/olympus/downloads.html
Trinocular heads are relatively common and cheap for my microscopes,
but a camera with Live View and HDMI output to an HDTV screen seems easier to view and focus,
at least for my aging eyes loaded with floaters.
For afocal with Canon APS-C, 40mm pancake lens works well.
Metaphot, Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic
Re: Imaging options for a binocular-head Olympus BH
I used a telescope t2 adapter tube and an eyepiece before I got a trinocular. Trinocular is better, I wouldn't spend much money on bino adapters, better wait for a trinocular head...
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