[TomB_tx]

I was mainly into photography in the 60s -70s (in terms of buying equipment), when the term "prime lens" wasn't used. Then there were "lenses" and "zoom lenses" - and zoom lenses were frowned on by "serious" photographers. Most lenses were single focal-length, so the zoom lens was called such, to differentiate it from "regular" lenses. Up through 2009 I used mainly my Leica rangefinders, and didn't buy any more equipment. But when I began looking at dSLRs I ran into the "prime" description for non-zooms. I assume when nearly all SLRs and dSLRs came with a kit zoom lens, the term "zoom" became redundant, since most lenses people used were zooms. So I'd guess the term "prime" came into being to distinguish a plain single focal-length lens.
I'm curious if anyone knows when this change in terminology became common. It really isn't correctly used, as it implies a special, select, or premium item. Although single focal-length lenses can be better, there have been a lot of "dogs" and cheap lenses as well, so "prime" isn't a good description - although it has certainly become embedded in popular talk now. It is at least a brief description, while "single focal-length" is clumsier to use. Yet I still think of "lens" as single focal, unless it is described as "zoom" - so to me "prime" is redundant or misleading.

[luftfluss]

Well, the original definition of "prime" is "one", or "first". This was prior to a more common useage of "prime" as being synonymous with "best".

I have no idea why the term "prime" came into use with regard to lenses, but the term "prime" in it's current usage is certainly correct - a single (one) focal length.

Edit: another thought, is it possible that "prime" was once used to describe the lens that originally came with the camera body? And once zoom came about, the term "prime" simply became attached to fixed focal length lenses?

[LaurenOE]

Prime.

It could be short for

Primarily - "It's primarily a single focal range"
Primed - "It's been primed to be best at a specific focal range"
Primary - "It's a primary focal lens - as in single - as in prime".

Dunno.

[blackcloudbrew]

In those days. I recall the term for the usual 50mm lens as the 'normal' lens every thing else was either a zoom, wide angle, or telephoto.

[boriscleto]

Prime lens - Wikipedia, the free encyclopedia

[TomB_tx]

Prime lens - Wikipedia, the free encyclopedia

Thanks! This quote from the Wiki link describes the way I remember it:

This use of the term "prime lens" is an example of a retronym. Early in photography only primary camera lenses were available, and were merely called "lenses" or "objectives". Later, "auxiliary" lenses were available, which usually fit in front of the front element of the primary, or "prime" lens.

Looking through my instruction manuals for the Pentax cameras from the H1a to the LX, and the Takumar and Pentax lens catalogs, and the Canon instructions and lens catalogs from the same era, the term "prime" is not found anywhere - they are just "lenses."

[Nesster]

It would be interesting to trace the first use of 'prime' when referring to a fixed focal length still camera lens. No doubt marketing had something to do with it.

I saw one other possible origin story for the term - from cine cameras with the rotating turret for different focal length lenses. The 'normal' lens was called the 'prime' lens.

[civiletti]

"Prime" is a silly name for a single focal length lens. Like many other silly names, we are likely stuck with it.

[kh1234567890]

"Prime" is a silly name for a single focal length lens. Like many other silly names, we are likely stuck with it.

I blame it on eBay - 'rare vintage 50mm f2.0 non-automatic prime' sounds much better than 'common as muck old standard manual lens'

[Moo]

The Oxford English Dictionary gives a quote from 1959: "At the flick of a finger he has at his filming disposal any three prime lenses of his choice."

[civiletti]

The Oxford English Dictionary gives a quote from 1959: "At the flick of a finger he has at his filming disposal any three prime lenses of his choice."

And how would we know from that whether the intended meaning of "prime" here is "single focal length"? Perhaps the reference is to class leading optics, or the distinction is made between "prime", meaning "main" and an add-on accessory lens.

[Moo]

Indeed, and I was actually going to say that in my original post, but then I thought "any three prime lenses" was probably as opposed to zoom. I'm thinking they're talking about some kind of lens-switching arrangement (rotating turret?), so stipulating non-zoom there would make sense. OED gives "prime lens" as meaning non-zoom, and this quote is listed in evidence of it... But yes, not entirely certain without seeing the context.

[gp1806]

How about a reference to numbers? A prime number can only be divided evenly by itself and 1. A zoom can be divided, 70/35=2, so it is called a 2 X zoom. A 50mm prime lens can not be divided, it is always a 50mm.
I'm just guessing here.

[civiletti]

How about a reference to numbers? A prime number can only be divided evenly by itself and 1. A zoom can be divided, 70/35=2, so it is called a 2 X zoom. A 50mm prime lens can not be divided, it is always a 50mm.
I'm just guessing here.

In that case, a 17-35mm zoom would be a prime lens.

[vonBaloney]

I've been using the term "prime" way before ebay came along -- since the late 80s. That's as far as I go back with photography so I've never NOT been familiar with it. We were talking about cine lenses much of the time, but also still photography -- zooms were in common use on movie cameras forever. For our movie cams with a turret of fixed focal length lenses, we called all of those lenses prime, not just the normal one -- we used it to distinguish from zoom, not any other meaning.