Olympus phase contrast objectives

[Harold]

Just getting started with phase contrast microscopy so I'm still gathering the necessary bits and pieces. Specifically objectives. In the process of searching Ebay, I've come across some LWD CD Plan PL objectives. Are these appropriate for BH2? Will they work as well as their non-long working distance counterparts? Thanks

[TonyT]

PM sent

[PeteM]

Especially at higher magnifications, you'll likely want phase contrast objectives corrected for a .17mm cover slip.

While plan achromats for better make good sense for brightfield work, especially if you want to take photos, my experience is that good achromats are OK for phase work with protists. They're moving around enough, you'll never get everything in plan focus . . .

[TonyT]

Harold expressed an interest in my Oly SPLan 20PL. I could not add an image to my PM, so they are here:
Top: with phase 'off'', note that one can see the tiny spikes on the hairs - high quality lens
Bottom phase 'on'; I am not fond of phase that's why I use DIC.
It's the dorsal surface of a tiny mite; diameter of outer circle = 0.42 mm

[PeteM]

Nice image.

[Harold]

Indeed. Very nice photos!! PM reply sent. Let me know what you think. Thanks for giving me the opportunity.

[Stew]

Beautiful images. Nice to see from a fellow maritimer.

Stew

[Tom Jones]

Remember, the LWD and ULWD CDPlan PL objectives are for the inverted Olympus IMT-2 microscope. The IMT-2 uses a different condenser than the upright BH-2 so the phase rings *might* not be the same size. I've never checked. The non-phase objectives should work. I have a friend who has been using them for some time on dinosaur bone specimens.

As for cover slips, the CDPlans have a correction collar that runs from zero (no cover) to 2 mm for imaging through the bottom of petri dishes.

[Rossf]

My two cents Harold-phase contrast shouldn’t be judged in imaging critters that can be easily seen in bright field-it often makes the image worse as TonyT’s photos show-bright field will always do a better job-sometimes phase can give a nice enhancement of say inner structures of ciliates and nematodes but phase contrast’ greatest strength and best application is in the imaging of ghostly hard to see protists (flagellates-amoebas-bacterial swarms-fungal mycelium etc)-these specimens really show the usefulness of phase in the right situation. The Splan PL objectives are really expensive! But then I’ve spent some pretty pennies on certain objectives… the simpler achromat versions (ie A20XPL) are very good also-the negative phase NH versions are nice also-hard to find…
Good luck with it-
Regards ross