Comparing DIN -> PLAN Achro -> PLAN APO images?

Starting out in microscopy? Post images and ask questions relating to the microscope and get answers from our more advanced users on the subject.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

fibreoptix
Posts: 2
Joined: Tue Jul 24, 2018 7:48 pm

Comparing DIN -> PLAN Achro -> PLAN APO images?

Post by fibreoptix »

Are there any visual comparisons online that demonstrate the differences between DIN, PLAN Achro and PLAN APO in terms of what to expect?

Overall I just want to gauge what to expect in terms of sharpness and clarity and compare it to price point.

Oh and pond water organisms would be the main specimen of interest if that changes things.

Thanks

enricosavazzi
Posts: 1474
Joined: Sat Nov 21, 2009 2:41 pm
Location: Västerås, Sweden
Contact:

Re: Comparing DIN -> PLAN Achro -> PLAN APO images?

Post by enricosavazzi »

fibreoptix wrote:Are there any visual comparisons online that demonstrate the differences between DIN, PLAN Achro and PLAN APO in terms of what to expect?

Overall I just want to gauge what to expect in terms of sharpness and clarity and compare it to price point.

Oh and pond water organisms would be the main specimen of interest if that changes things.

Thanks
I have no comparison, but I recently posted a few images of freshwater organisms taken with Olympus UPlanApo 40x 0.85 and DIC. In my opinion, this objective gives a very good resolution and no chromatic aberration that I can detect. I don't claim to be an expert, but I have noticed that good equipment makes things easier unless one is doing some basic mistake.

http://www.photomacrography.net/forum/v ... hp?t=37826

Direct comparisons are hard to come by, because this would require one to own, or at least borrow, achromat, plan achromat, plan FL and/or plan apo objectives of the same or similar NA and test them on the same system and with the same subject. In general, the choice for an amateur microscopist is a compromise between what is available on the second-hand market at an acceptable price and within a reasonable time. At least among objectives of the same approximate age, plan apos are usually the best and most expensive, with plan FL second in both respects. Achromats are usually at the bottom of both scales.

My recommendation would be to buy the best that you can afford, and to be prepared to wait some time (months to perhaps one year) if what you need is not immediately available at a reasonable price. If your goal is to assemble a system in a shorter time, you may have to spend more. Some components are however so rare that it may take years to assemble a complete system, and in this case you may want to change plans and get components that are cheaper and easier to find, or good enough to use for a few years while you are waiting for the top-notch items to become available.

Achieving the best image quality with a plan apo or plan FL objective depends on many additional factors, including the quality of the condenser (aplanat achromat is usually better than plain Abbe), correct adjustment and type of illumination, quality of DIC or phase components, choice and preparation of the subject, and skill of the microscopist.
--ES

Pau
Site Admin
Posts: 6053
Joined: Wed Jan 20, 2010 8:57 am
Location: Valencia, Spain

Post by Pau »

Hi fibreoptix, welcome aboard!

I concur with what Enrico said.

DIN is only a standard specification for finite corrected microscopes (RMS thread, 45mm parfocal distance and 160mm mechanical tube length), the most usual in instruments made in the 50s - 80s decades and still very widespread in school grade microscopes. Nobody still makes DIN plan apos and there are few plan fluorites ones. You can still find excellent used DIN objectives and instruments.

To get good results you don't need the best instruments, plan achromats ("Plan" or "Pl") of reputed makers are good, although Plan Apos are arguably better and much more expensive, Plan fluorites or Plan semi-apos are a good intermediate range.
More info at:
https://www.microscopyu.com/microscopy- ... objectives
http://www.microscopy-uk.org.uk/mag/ind ... romat.html

A comparison between pl fluor and pl apo:
http://www.photomacrography.net/forum/v ... 395#123395

For pond life a most important factor is contrast, provided that the whole organism or some of its parts is transparent and colorless in most cases.
You want ro be able to use optical contrast methods: dark field, phase contrast, oblique illumination and DIC are the main ones. DIC is delicate and very expensive even in old used instruments although in many cases the best one. DF and oblique are much more affordable and can provide excellent images, Phase is very powerful highlighting thin structures although easily produces unpleasing halos.
Pau

JohnyM
Posts: 463
Joined: Tue Dec 24, 2013 7:02 am

Post by JohnyM »

Pau wrote:Nobody still makes DIN plan apos...

...A comparison between pl fluor and pl apo:
http://www.photomacrography.net/forum/v ... 395#123395
Nikon still manufacture finite RMS objectives, with at least one PA objective (4x).

This PA/PF comparision is better than nothing, but it should be pointed that it's rather inaccurate.

Post Reply Previous topicNext topic