PKR
Veteran
There has not been separate East (Jena) and West (Oberkochen) German Zeiss entities since the early 1990s. It is all Carl Zeiss AG now.
I have Zeiss, Leica (Microsystems, different company to Leica Camera) and Nikon Microscopes in my labs. All microscope lenses need cleaning after immersion use because the oil dries, and as it does so, it traps dust that compromises image quality and causes optical problems such as uneven image illuminance, and long term, fog. Dried oil can deteriorate the objective lens over time, but it mainly affects coatings and does not dissolve cements. Zeiss T* coatings are definitely the best, but ALL microscope manufacturers recommend cleaning the immersion oil off your objectives immediately after use. The oil is still wet then, and is easy to remove.
Nikon, Olympus and other companies have no particular problem in that area. I have a Zeiss (West Germany) Photomicroscope III at home whose lenses were made in the mid 1970s and has been used weekly with immersion oil for at least 30 years. Lenses are still great. Keep them clean, get it serviced, no problem, same as any other optical instrument.
Marty
Hi Marty,
The story is years old so, it's likely out of date as per your info. I know, the school spent a lot of money on microscopes at the time and then, struggled to get an Electron Microscope for the research lab. Local businesses contributed to the fund, which is unusual.
As for Nikon, i know they make decent instruments. I'm sorry to see them in this situation. Camera Phones certainly killed the small consumer cameras that all Cos made. I guess, Covid is taking a further toll? And, i'm sure, from past stories, poor management caused lots of trouble.
pkr