Wanted...OLYMPUS OM-MOUNT PHOTOMICRO ADAPTER L

Don Parsons · Post by **Don Parsons** » Mon Oct 01, 2018 12:08 pm

I'm looking for a OLYMPUS OM-MOUNT PHOTOMICRO ADAPTER L.

Don

enricosavazzi · Post by **enricosavazzi** » Mon Oct 01, 2018 12:31 pm

If no member has one available, this adapter usually is offered on eBay a few times a year (at much variable prices).

It has no built-in optics, so in principle an equivalent photo tube could be custom-built with extension tubes and adapters.

genera · Post by **genera** » Mon Oct 01, 2018 2:13 pm

The Diagnostic Instruments PA1-10A can be used in place of the Adapter L. It has the same length, once a OM - T adapter is added, and clamps on to the same dovetail as the Adapter L.

Tom Jones · Post by **Tom Jones** » Mon Oct 01, 2018 8:43 pm

Don,

Genera is right. The PA1-10A works just fine on either the BX or BH2 series. I have a spare I'll let go for $100 plus shipping.

Tom

dolmadis · Post by **dolmadis** » Mon Oct 01, 2018 10:29 pm

enricosavazzi wrote:It has no built-in optics, so in principle an equivalent photo tube could be custom-built with extension tubes and adapters.

Does any one have the accurate dimensions please?

Might be useful to Don and certainly to me !!

BR

John

enricosavazzi · Post by **enricosavazzi** » Tue Oct 02, 2018 12:01 am

dolmadis wrote:Does any one have the accurate dimensions please?

Might be useful to Don and certainly to me !!

I have one and can measure it if/when I can find it (already packed away for the next move, but finding it is not entirely hopeless).

The following general information is probably already known to Olympus microscope owners, but just in case, here it goes:

The L adapter with Olympus OM bayonet is primarily interesting for attaching a full-frame or APS-C camera to an Olympus microscope (mostly BH, BX etc.). The photo eyepiece to use with full frame is the 2.5x. 3.3x works but it covers a rather small portion of the FoV. 2x and 1.67x (good luck finding one) work for APS-C.

For Micro 4/3 on a BX scope it is best to use an adapter with C mount without any optics (i.e. direct projection from tube lens to sensor) + a C to Micro 4/3 adapter. Much shorter and much cheaper than photo tube + photo eyepiece + L adapter + OM to Micro 4/3 adapter.

The U-SPT tube is necessary on BX scopes and mounts between trinocular head and L adapter (or another photo adapter. e.g. with C mount). The U-SPT and the BH photo tubes fit Olympus photo eyepieces with a non-standard barrel diameter (you cannot put here an ordinary eyepiece).

Both old (finite) and new (infinity corrected) Olympus photo eyepieces fit (mechanically) both finite and infinity microscope photo tubes. All these photo eyepieces look similar except for the markings, however the finite/infinity series might be optically different. Olympus NF and NFK series photo eyepieces are used on finite scopes like the BH series. PE series photo eyepieces are used in infinity corrected scopes like the BX series.

dolmadis · Post by **dolmadis** » Tue Oct 02, 2018 12:05 am

enricosavazzi wrote: PE series photo eyepieces are used in infinity corrected scopes like the BX series.

When an intermediate tube for infinity is added to BH2's using infinite objectives can you then use the PE's?

BR

John

enricosavazzi · Post by **enricosavazzi** » Tue Oct 02, 2018 12:28 am

dolmadis wrote:
enricosavazzi wrote: PE series photo eyepieces are used in infinity corrected scopes like the BX series.
When an intermediate tube for infinity is added to BH2's using infinite objectives can you then use the PE's?

BR

John

Unfortunately, I have no idea how/whether converting a Bh2 to infinity corrected would work. The tube lens sits at the bottom of BX mo/bi/tri/nocular heads, so if you get a good IQ through the observation eyepieces after mounting on the BH stand infinity objectives and a BX head, then you can continue to build up the system with infinity corrected components above the head. This would mean (for full frame) U-SPT, PE2.5x, L and the final adapter for your camera.

Pau · Post by **Pau** » Tue Oct 02, 2018 12:28 am

dolmadis wrote:
enricosavazzi wrote: PE series photo eyepieces are used in infinity corrected scopes like the BX series.
When an intermediate tube for infinity is added to BH2's using infinite objectives can you then use the PE's?

AFAIK old infinite metallurgical Oly objectives do need corrective eyepieces like finite 160 biologicals while modern UIS/UIS2 infinites are fully corrected, so the answer will depend of the kind of objectives used.

dolmadis · Post by **dolmadis** » Tue Oct 02, 2018 12:34 am

That clarification on the options is helpful.

John

Alan Wood · Post by **Alan Wood** » Tue Oct 02, 2018 2:11 am

If you want to make your own adapter, then the distance from the ledge on which the top part of an NFK eyepiece rests to the film/sensor is 150.0 mm.

http://www.alanwood.net/photography/oly ... s.html#125

There are, or have been, at least 3 alternative adapters:

http://www.alanwood.net/photography/oly ... eraadapter

The PE photo eyepieces are wider than normal eyepieces. They do NOT fit the Olympus BH2-TR30 trinocular head or the PM-ADF eyepiece adapter.

Alan Wood

Tom Jones · Post by **Tom Jones** » Fri Oct 05, 2018 8:04 pm

I found I have one I'll sell. PM sent.

Tom