Choosing a good phase contrast microscope.

[Zwei²Lines]

Greetings.
I've been using brightfield microscopy for several years now and I want to get my hands on a good phase contrast microscope. The question is, which?
I've known about older pieces like the M20 Heerbrugg, and it definitely seems rather excellent despite it's age. (Or because of it?). I should mention that my budget is within the range of around 1000 euro, since that is a major factor to consider.
If you own any good phase contrast sets, please let me know what you think about them. I'd love to hear about them

Regards.

[apochronaut]

If you are buying new, you have to step up to the tier 2 Chinese or Indian microscopes to get good. With those systems the phase condenser and objective set is around 1,000.00 alone.

Since you are in Europe, I would look into any of the main continental makers of the past and the later Japanese. The two Zeisses, Leitz, Reichert, PZO plus Olympus, Nikon and Meiji plus your Wild.

There are a couple of things to consider. First is how complete the system is. Second , does the possibility to have an expansive system exist . Some makers had various phase types, such as anoptral, negative, positive, dark, bright. The more possibilities the better. Third, there has been a bit of a revolution in the field of view offered by microscope manufactuers since about 1990 or so. With many manufacturers the default was 18mm but with some, wider options existed with special equipment. Others had a default of 20mm. PZO for instance had a relatively complete system including anoptral on a nice stand( The Biolar) but they only had 18mm. However a PZO Biolar can be had quite cheap. You may have to buy out of Poland. Reichert had a very diverse system and by the 70's was offering 20mm f.o.v. on the infinity stands. Again, not as easy to find as something like Leica or Zeiss, Nikon or Olympus but the system is as expansive as any , with the exception of Nikon and AO. AO is another option but there are very few in Europe
All companies offer dark phase which is the default phase system.
Some of the better makers tackled the phase halo problem with varying degrees of skill. That is a contrasting band of optical distortion that radiates from the subject and is present in all phase images to more or less of a degree. Reichert were very good in that regard. I believe, Zeiss Jena too. Cheaper phase systems can be poor and that is one of the reasons to avoid them.
I would just look on various country's ebay sites and see what is available and take it ftom there.

I don't think it matters who made the system, as long as it is complete, in excellent working order and priced well. Don't hesitate to ask questions. There are a lot of members here who have various mfg.'s phase systems and will likely know the answers.

You did not mention what your existing stand was and why you have ruled out getting objectives and a condenser for it?
You can usually use a phase condenser as a BF condenser too but often it makes more sense to get a dedicated stand than fiddle around swapping objectives.

[Galf]

The amount of knowledge of Apochronaut is staggering, I have only 2 cents to add.

Since I have this near mint Leitz microscope from the seventies-era (SM-LUX) that already had a phase contrast condenser, just for the fun of it, I started looking for parts to make it more functional.
It is from the 170mm tube length time which might be a disadvantage when interchanging objectives and oculars with other types. Field-of-view is 18mm which might be considered outdated as well. And it has only positive phase contrast with the standard objectives so nowhere near the capabilities of other brands I learned above...

But with the Periplan GF 12.5x eyepieces it is just a delight to drown in the view. Optically no complaints! Fine hardcore quality, still going strong after almost half a century and probably long afterwards.
As said above it is important to have a complete set, initially missing the centering tools and the focus telescope to match the phase rings in the condenser with the objectives, gave quite unimpressive results which I only recognized after tuning the condenser and matching the phase rings.

I have no other experience and other brands or types to compare but so far I'm quite impressed with the new possibilities of my 'oldie'. So it might be possible to upgrade your existing gear well within your budget limits.

[BramHuntingNematodes]

I have a Wild phase contrast lens and it's very good. They also made several in higher NA fluorites which is not too common a practice. These can be had for a mid-range price here in the states, maybe even cheaper in Europe not sure. You could do worse!

[PeteM]

I've had phase contrast systems from AmScope (infinite), American Optical (short barrel infinite), Leitz (finite), Leica (infinite), Lomo (finite), Nikon (short and long barrel finite and infinite), Olympus (short and long barrel finite and infinite), Reichert (infinite DIN) Wild (short barrel finite), and Zeiss (finite DIN).

Frankly, they are all pretty good. It seems to me that the only affordable new choice is something like a Chinese (AmScope, Omax etc.) plan achro system - and not one of the top choices. The best systems (probably beyond your price range if newer ininite systems) tend to use fluorite phase objectives. The Zeiss Neofluors (but older and with only an 18mm field) should be under 1000 Euro. Olympus UplanFl phase and Nikon Plan Fluor phase will be more.

All of which is to say that finding a good and complete used phase scope from any one of several brands could leave you delighted; with the specific model depending a bit upon what shows up in your area.

If you're doing mostly pond critters, you might consider an inverted scope - these are often a good deal and ideally suited to that subject.

A very rough ranking of systems, somewhat in order of capability and price might be:

Somewhat limited in one way or another (but stil quite good):
- Older short barrel name brand scopes like Lomo, Nikon, Olympus, and Wild (fluor and apo phase often show up cheap; lamps tend to be dim)
- Older Japanese plan phase scopes badged Fisher MicroMaster etc.
- Chinese achro phase scopes, such as AmScope and Omax. Plan achro phase even better.

Oldies but goodies
- A.O. Series 10 with advanced plan achro phase and 20 watt halogen lamp
- Zeiss Standard, with plan phase and sufficient illumination or LED retrofit

Newer mid range Chinese imports
- AccuScope, Motic etc. infinity scopes from past 10 or so years with plan fluor phase objectives

Solid pro scopes from the finite area (and also Reichert infinity) - and also darkfield capabilities
Big plus with these is lots of reasonably priced accessories available on the used market
- Leitz Plan Achro and Plan Fluors
- Olympus BH2 with at least plan phase
- Nikon Labophot/Optiphot with at least plan phase
- Zeiss Standard with removable nose, brighter lamp, Plan Neofluor phase
- Reichert 410/420 with advanced plan achro phase (good scopes, not so many ugrades easily found)

Newer professional scopes from the infinite era (getting pricey)
- Leica DMLS, DMLB, etc. with C or N plan phase
- Olympus BX40 the cheapest entry point
- Nikon Eclipse E400 with plan achro
- maybe Zeiss Axio (haven't owned one)

Still a step higher
- Leica DMR etc. if complete with Plan fluorite phase
- Olympus BX with UPlanFl N phase
- Nikon E600 with Plan Fluor phase

Nirvana within an ample hobbyist budget
- Various DIC systems - or perhaps clever use of oblique, Hoffman modulation etc. on a quality stand

No doubt others will have experience with still more phase or contrast-capable scopes.