Leitz Diavert, modernization (kind of)

[Rorschach]

Hi people,

I was recently looking for info on the Wild M40 inverted microscope, one of which my university unit still has for field course teaching purposes. That scope has not been maintained very well and is obviously very long in the teeth.

Anyway, on that googling trip, I bumped into this article, and a couple others from the same author: http://www.microscopy-uk.org.uk/mag/ind ... ldm40.html Seems very encouraging that one can take a mechanically superior old microscope (no plastic gears etc.!) and pimp it up by adding much more modern optics on it. Definitely gave some food for thought on that poorly maintained relic scope.

I also started to think that perhaps also a little newer (by a decade or two) inverted scope classic that is also known for very high mechanical quality, the Leitz Diavert, could be significantly upgraded. What would immediately come to mind is using Labovert 160mm tube length objectives on the 170mm tube length Diavert (both use 45mm barrel length objectives, unlike the venerable Wild M40). Among those objectives, there should be options that are optically far superior to the old Diavert objectives. What makes these choices even more appealing is the fact that the Diavert is very compatible with Ortholux II and Metallux II parts, including condensers and nosepieces etc.

I suppose the 'high-end' option would be to put Olympus IMT-2 objectives on the Diavert, Splans or even the Plan Apos that were available for that scope. However, no idea which eyepieces would then work with that Frankenscope. Has anyone tried?

There are also several quality LED conversions available for the Diavert, further improving it's case.

As a side note, I know that Diavert came out in mid-70ies but I don't know when they stopped producing DIaverts? And what was the successor, was it Labovert, which is very, very different in many ways. Labovert also apparently is an epitome of mechanical and optical complexity if one looks at the innards - the polar opposite of Diavert simplicity!

[Alexander]

The direct successor of the Diavert was the DL IM. First under the Leitz brand then Leica. Under Leica brand it made the change from finite to infinite optics. The Labovert was a very special animal standing separately.

When using Olympus objective the fitting Olympus eye-pieces will give best results. HoweverI cannot recommend the use of plan-apo's on an inverted scope. Free working distance is a problem. I learned that the hard way by purchasing a Leitz NPL-Fluotar 10/0.30 which was not useable due to its working distance of 0.2 mm. An inverted scope needs LD-objectives. Same with condensers. You need one with proper working distance.

Many Diaverts and absolutely all Laboverts suffer from hardened grease. The focus mechanisms of both are quite complex and not easy to maintain. Be careful with your buying decision.

Look into the DM IL. as well. They are found at reasonable prices then and then.

[Rorschach]

The direct successor of the Diavert was the DL IM. First under the Leitz brand then Leica. Under Leica brand it made the change from finite to infinite optics. The Labovert was a very special animal standing separately.

When using Olympus objective the fitting Olympus eye-pieces will give best results. HoweverI cannot recommend the use of plan-apo's on an inverted scope. Free working distance is a problem. I learned that the hard way by purchasing a Leitz NPL-Fluotar 10/0.30 which was not useable due to its working distance of 0.2 mm. An inverted scope needs LD-objectives. Same with condensers. You need one with proper working distance.

Many Diaverts and absolutely all Laboverts suffer from hardened grease. The focus mechanisms of both are quite complex and not easy to maintain. Be careful with your buying decision.

Look into the DM IL. as well. They are found at reasonable prices then and then.

Thanks for the info! Yes, of course, how could I forget the DM IL!

I think there was a special Plan Apo series made for the Olympus IMT-2 and these had a longer working distance. However, you are right that this is crucial and needs to be verified. In any case there are the excellent Olympus Splans and LWD CD Plans, many of which are amenable to DIC too.

Yes, hardened grease is always a problem in the older scopes. At some point it may be necessary to clean and relube the focus mechanism, which is never an easy task. But Laboverts are several levels more complicated than Diaverts from what I hear, both mechanically and regarding the optical paths.

[MichaelG.]

I think there was a special Plan Apo series made for the Olympus IMT-2 and these had a longer working distance. However, you are right that this is crucial and needs to be verified. …

Having just started my journey in the opposite direction [bought an IMT-2 yesterday], I will post links, later today, to the Olympus documentation that I have so-far found.
You might find these useful for identification.

MichaelG.
.

The early IMT brochure: https://www.alanwood.net/downloads/olym ... ochure.pdf
The early IMT manual : https://www.alanwood.net/downloads/olym ... manual.pdf
.

IMT-2 brochure : https://www.alanwood.net/downloads/olym ... ochure.pdf
IMT-2 manual : https://www.alanwood.net/downloads/olym ... ctions.pdf

[Rorschach]

I think there was a special Plan Apo series made for the Olympus IMT-2 and these had a longer working distance. However, you are right that this is crucial and needs to be verified. …

Having just started my journey in the opposite direction [bought an IMT-2 yesterday], I will post links, later today, to the Olympus documentation that I have so-far found.
You might find these useful for identification.

MichaelG.
.

The early IMT brochure: https://www.alanwood.net/downloads/olym ... ochure.pdf
The early IMT manual : https://www.alanwood.net/downloads/olym ... manual.pdf
.

IMT-2 brochure : https://www.alanwood.net/downloads/olym ... ochure.pdf
IMT-2 manual : https://www.alanwood.net/downloads/olym ... ctions.pdf

Yes, on page 11 of that IMT-2 brochure, those D Plan Apo lenses are depicted.

Thanks for putting these here. I have already everything relevant from Alan Wood's excellent site but didn't have access to my copies when posting the thread

[MichaelG.]

Interesting to note that the designation for those two includes UV … but doesn’t mention either LWD or ULWD

… looks like a long and winding road ahead !

MichaelG.

[MichaelG.]

https://earth2geologists.net/Microscop ... ctives.pdf

[Rorschach]

https://earth2geologists.net/Microscop ... ctives.pdf

Thanks. This is a good overview of that Olympus objective series.

I'll probably first look at the Leitz Labovert line of 160mm tube length objectives. They may provide the best quality/cost ratio.