nikon BD vs M objectives

[phansen39]

Have a stripped optiphot inbound and was looking at objectives. Considering between Nikon M and BD. The Vertical illuminator i ordered is this one. This has the lever to bring the light around the outside or through the center of the optics. If I'm correct It would work with BD objectives. I know about the thread size difference. rms and m26. Still need to order the nosepiece. The purpose of this is to compliment my stereo zoom scope for hobby electronics. Looking at boards and decapped ic's. Am I on the right path. and which objectives bd or M. Thanks
.

[blekenbleu]

The purpose of this is to compliment my stereo zoom scope for hobby electronics.

How are you currently illuminating objects with the stereo zoom scope?

which objectives bd or M

I favor BD.
We compete with macro photographers for M Plans, so usually somewhat higher prices than BD,
particularly those with longer working distances.

FWIW, 26mm to RMS reducers exist for installing M Plan objectives in BD turrets.

Without longer working distances, bright field illumination is pretty much unavoidable for opaque objects and M Plan > 10x.
Bright field EPI illumination means a lot of non-image light reflecting back to oculars, wanting crossed polarizers to subdue.

M Plan objectives also want a vertical illuminator with field aperture, which yours lacks.

You probably already have contemplated or even acquired some illumination source; if not, consider an LED pin spot light:

https://www.amazon.com/dp/B084JQ55B1
https://blekenbleu.github.io/microscope/pinspot/

[phansen39]

144 white Led Ring light on the stereo zoom. good for soldering.

For the vertical illuminator. Ordered a pair of motor cycle fog lights. Has white and amber leds. Only going to use the white. Remove the front lens. design and print an adapter etc
This is the light. Pretty small has an integrated heatsink and fan.
https://www.amazon.com/dp/B08GS4QTZN?ps ... ct_details.

[blekenbleu]

This is the light. Pretty small has an integrated heatsink and fan.
https://www.amazon.com/dp/B08GS4QTZN.

That is a lot of light; hope it dims gracefully.
Fan may provoke vibrations; may want isolating instead of rigid attachment.

[phansen39]

When you say field aperture. Something like this?
https://www.amazon.com/Adjustable-Apert ... 1220?psc=1

[blekenbleu]

Something like

Yes, but...
Compound microscopes have conjugate planes:

https://www.quekett.org/resources/under ... lumination

... arranged differently for reflected illumination:

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

To manage stray light effectively, field diaphragm has to be specifically located.
That is why Nikon also made longer vertical illuminators for Optiphot:

• to incorporate field and aperture diaphragms.

• https://www.youtube.com/watch?v=60_jgZtyR6U

[phansen39]

Thanks. Not going to worry about it then.

[blekenbleu]

Not going to worry

Bingo! Polarizers are helpful even with darkfield illumination;
sourcing one that fits and spins in an illuminator filter slot
and another to stuff between the head flange and illuminator
will be worthwhile

[Scarodactyl]

I would guess there might be a fixed polarizer and analyzer in that simple illuminator but I could be wrong.
You'll probably want to eventually get the more advanced illuminator with the rotating polarizer (really easy to find without the rotating polarizer, the polarizer is the expensive part for whatever reason).
I assume the m plan and bd plan are similar or almost identical optically, though I haven't tested it. The BD plans perform quite well, and are essentially plan fluorites in correction.

[phansen39]

Got the above illuminator is unfortunatly has a chip in the glass. Mounted it into the labophat 2 I can see it clearly. Will see if I can return it.
But this complete illuminator came up so I jumped on it.

[Scarodactyl]

That is the good model, but it may have an ND filter slider installed where the rotating polarizer goes, and possibly no analyzer too. If you have a 3d printer these would not be too hard to replace by printing a new frame and putting a cheap film polarizer. Or you may be fine with it as is.

[blekenbleu]

That short illuminator might be salvageable by inserting a (ground glass) diffuser in one of its filter slots.

Nikon analyzer goes in that gap in the front of that universal epi-illuminator


... has a circular polarizing filter and looks like this:


The polarizer which replaces that ND filter slider has two parts;
one slider has an ND filter and optionally a lambda plate:

Those two parts could be fairly easily duplicated by 3D printing,
then ordering lambda plate from e.g. techno2020 https://www.ebay.com/str/techno2020

Someone used to sell 3D-printed rotating polarizer sliders on eBay, but not lately,
and they were a poor fit for that illuminator:


The hard-to-obtain slider polarizer rotating ring looks like this:

[phansen39]

On the rotating slider. Do you know the diameter of the filter itself?

also would I want the 1/4 or full lambda plate?
Thanks

[phansen39]

Bit of tinkercad for the polarizer

[Scarodactyl]

Looks promising!