MicrobeHunter.com Microscopy Forum

When it comes to comparing optics quality and build , what's the difference in between Neoplan and Plan Acro?
I got two 410s one with an internal QI sticker dated 1985 Reichert, the other 1989 and its branded Leica
The Reichert cane with Neoplans
The Leica Planacro
While cleaning them under my stereo I noticed first the weight was different, so was the girth of the barrel, but the most peculiar thing are the distal lens, for example when comparing the Cat 1734 and 1757 both 40X, I noticed that the 1734 lens look different, the aperture seems a lot larger and so does material...... What is going on here?

Pretty sure the plan achro has a slightly wider plan view.

Thank you, what about the Eyepieces, The newest acquisition came with Cat 191 instead of the 181, were the 191s corrected for a vertical Illuminator?

*** This is probably by eyesight, but after making sure all of the objectives were squeaky clean, I notice a much crispy picture with the neoplans when compared with the Planacro 40, 100, specially when focusing in to some diatoms, the colors seem more vibrant and more detail can be seen, the Plans by comparison dull the image

Plasmid wrote: ↑

Thu Nov 18, 2021 1:43 am

Thank you, what about the Eyepieces, The newest acquisition came with Cat 191 instead of the 181, were the 191s corrected for a vertical Illuminator?

*** This is probably by eyesight, but after making sure all of the objectives were squeaky clean, I notice a much crispy picture with the neoplans when compared with the Planacro 40, 100, specially when focusing in to some diatoms, the colors seem more vibrant and more detail can be seen, the Plans by comparison dull the image

As PeteM said, I'm pretty sure the plan achros are supposed to be a better design, I believe the neo plans were an entry level/education model, but that's based mostly on just what I've read here (mostly from apochronaut). What little testing I did with the same mag objectives suggested the plan achros performed better, but I don't know I would trust my opinon.

The 191 eyepieces are from the ATC2000 I believe, I think I have a set around here but I haven't really compared them against the 181's (which are the default for the 410). I have a 191 in the trinocular head on my 410, but I don't use the 410 as much as the AO10 lately so haven't really compared them. Thinking of which, I need to finalize the design on the trinocular head adapter for the 410 and upload it to thingiverse....

The usage of "neo" here appears to mean "very nearly" or "almost." I don't remember what it means when Olympus uses it.

Olympus used it to mean brightfield/darkfield objectives.

Interesting to see Leica branding on a microscope from 1989, a little before the company formed. Sometimes the rebranding was as simple as a sticker over the older name.

Following on from Bram’s comment :

The translingual entry at https://en.wiktionary.org/wiki/neo-#Etymology nicely illustrates the ‘slippery’ usage of Neo-

Ref. __ https://www.fecundity.com/pmagnus/humpty.html

MichaelG.

With AO, one has to speculate some, since at some point the 400 project went from winding up to winding down. The whole program was launched prior to Leica and prior to Reichert likely but by 1985 and the series introduction, Reichert branding had taken place. By 1989, the production year of your newest scope, Reichert branding was still taking place. Probably, your scope body was in a queue waiting to be sold or at a dealer. There might have been a time after which the corporate brass required all branded items to be badged Leica. All kinds of things got badged Leica....even Bausch & Lomb Balplan objectives.

AO clearly saw no future in offering achromat objectives for a lab and small research stand. Sometime during the series 400 development, there was a decision to replace the aged but utilitarian 150 with a 45mm parfocal replacement. The ATC 2000 became the heir apparent, tuneable to use planachros or lowly achros for educational to small lab applications ( vet clinics etc.) . It had phase too.

They did however see a need for an objective series. The Neoplans were the budget line with only 4 magnifications available The planachros were the common workhorse line with 6 magnifications plus an iris equipped 100X. The planfluor were the research oriented line with 3 magnifications plus a briefly offered 100X with iris.
Having used all of them, except the two iris equipped 100X, here are my perceptions of the differences.

The Neoplans were, as pointed out above, not quite plan. There is a very slight lack of full planarity at a 20mm f.o.v. The image circle is at it's limit at 20mm, whereas the planachros are fully plan at 20mm and possibly at 24 as well. That coincidentally, is the f.o.v. of the 30mm barrel Polyvar eyepieces. Ditto for the remarkably well corrected Planfluor objectives. Plans for the future? A 24mm f.o.v. Diastar, with wings clipped at the merger? They clearly had planned a 60X and a fuller range of Neoplans.
There is almost no difference in the image quality up to about 19mm f.o.v. between the the Neoplans and Planachros. Your observation that the 40X and 100X Planachros have inferior image quality to the Neoplans is likely due to some other factor. Possibly, they both have defects of some kind? Check your cleaning with oblique light but smearing usually causes a loss of contrast.

#191 eyepieces as far as I can see are the same as 181 in performance, just having a locking ring on the lower barrel, a necessary feature where prying fingers abound, such as in schools. Hence they show up mostly on the ATC 2000.