Phase condenser compatibility

[saltineSandwich]

While reading through my microscope's manual I came across a section talking about the phase contrast system and it grabbed my attention with its claims. After some hunting on ebay I found the original phase contrast objective but no condenser. So my question is if I were to buy a correctly sized condenser from a different brand/model would it still produce the phase contrast effect? Thanks in advance.

[Alexander]

Most probably not. This is gambling, nothing else.

[saltineSandwich]

Most probably not. This is gambling, nothing else.

Got it. Thanks.

[BramHuntingNematodes]

I got two versions of Nikon's phase condenser, tiyodas phase condenser, a couple Bausch phase condensers and among those are four different sizes of annuli. I'm still in the look out for B&L flat field phase condensers as while the standard turret works ok for the 20, 40 and 100, the 10 is no good. They also work on the Galen plan phase objectives. The two Nikon condensers are not compatible. The Tiyoda works ok on a few Wild objectives I use to have, but I wouldn't bet all of them out there. I have made a few condenser diaphragms myself to some success.

The best phase effect also comes from a very close match of the ring to diaphragm. This prevents excess artifacts, and Nikon has a line I think called apodized phase that requires extremely tight tolerance to function best. So yeah, it's a gamble. You can probably get some.phase, but not ideal. Still, often some is better than nothing, and a good turret can also produce COL, some oblique and limited application darkfield

[PeteM]

It's possible to make your own phase rings - or buy closely-sized ones on Ebay that are laser cut from Delrin - and install these in a phase condenser. It's reasonably easy to measure the rings. A bit harder to find a match and then adapt it to the proper-sized carrier for your condenser -- but sometimes the best option for a match.

Otherwise, as others have said, the match between different brands and even generations within a brand is pretty much a matter of luck.

Generally speaking it's best to find a complete set of phase objectives and the matching phase condenser.

[saltineSandwich]

Interesting. I've heard the term annuli a couple of times now, are those the "patches" that swing under the condenser lens? I'm looking for a condenser for a swift m1000d, I believe they have named it the quodmaster and is part of the quodlibet system . Best of luck with finding what you're looking for.

[apochronaut]

Annuli, the plural of annulus more properly describes the group of rings embedded in the various phase objectives, whereas annular diaphragm describes the ring that is fitted into the condenser. Each annular diaphragm has a matching annulus in an objective.
Phase condenser is a bit of a misnomer. It isn't the condenser itself that contributes to phase performance, although condensers used for phase can be optimized for the job, it is the diaphragm that does the job.
Theoretically, a sort of iris diaphragm with two concentric adjustable sections ; an outer coronal iris and an inner expandable spot stop or reverse pupil could be designed as a universal phase diaphragm to work with any phase objective.

[BramHuntingNematodes]

If I ever find a source of reasonably priced axicons I have some experimental designs I would like to try