What’s in a name?
Names are – first and foremost – identifiers. The purpose of names is to both separate (John and Jill are distinct) and unify (the Volkswagen Transporter and Volkswagen Golf have something in common).
When we’re talking about lenses, the point is to say that a Nikkor AF-D 50 f/1.8 and Nikkor AF-D 50 f/1.4 have commonalities (Manufacturer, autofocus, focal length) and differences (max. aperture). Moreover, if you encounter two lenses that have identical identifiers (e.g. two lenses that both are named “Carl Zeiss Ultron 1.8/50”), it is reasonable to assume that the lenses are quite similar, and that whatever differences the lenses may have had when leaving the factory (m42 or Icarex BM mount) are relatively insignificant.
Today it is rather typical for lens names to contain: manufacturer (e.g. “Tamron”), product family (“SP”), focal length(s) (“15–30 mm”), maximum aperture (f/2.8) and a list of acronyms denoting the technologies used (“Di VC USD”) and maybe even a version indicator (“G2”).
On the other hand, as vintage lenses were not “Digitally integrated”, did not have “Vibration Correction”, and had no autofocus motors legacy lenses typically had fewer acronyms. Instead they may have had a letter or two to denote the number of lens elements/groups used in the design, such as for instance: “Minolta ” (manufacturer) “Auto Rokkor” (aperture communication technology family) “–PF ” (number of groups and number of lens elements) “1:1.4 ” (maximum aperture) “f=58mm” (focal length), followed by a serial number.
YMMV, but I’ve always been fascinated by names and terms, and – in my previous research into the naming practices/logic of Meyer-Optik Görlitz – I gathered some other naming-related information, which has now taken the form of two more articles:
• One article on the lens naming logic used at Carl Zeiss (Pre-war, East, West, and post-unification)
• One article on the naming logic used by Japanese optics companies.
There are, obviously, more naming/terminology – related matters that still deserve a discussion (Leica naming logic? Acronyms and common terms?) and these may – one day – each deserve their own article.
In the meantime, enjoy.