Nope, not even close. Some used 135 film (35mm format), some 120 film (medium format), some 127 film and there were other formats as well. On 120, an 80mm is “normal”. Not sure what is “normal” on a 127.

- 135 has 2 sizes, 24mmx36mm & 24mmx18mm. Cameras include SLR, range finders & possibly others.
- 120/620 has several sizes that up include 6cmx4.5cm, 6cmx6cm, 6cmx7cm, 6cmx8cm, 6cmx9cm, 6cmx12cm, 6cmx17cm and possibly more. Cameras include SLR, range finders, Twin Lens Reflex (TLR), view camera (6cmx17cm), folding below cameras & possibly others.
- 127 has 4cmx4cm, 4cmx3cm & 4cmx6cm, possibly more. Cameras include SLR, TLR, box & possibly others.

Who knows what will be the standard 10 or 20 years from now? I suspect we will be moving to better but smaller sensors and lenses. There is nothing sacred about the old 35mm film size, and it seems silly to base everything on it. A growing number of people have never used any film camera. I think we should call lenses what they are and the user can see what the do on the camera at hand. "Crop factor" probably made sense at the time, when it took a "full frame" camera to get a picture with the size and image quality of one taken with a 35mm film camera. We get that now with smaller formats. Just my 2 cents' worth.

I am a psychologist so I claim some expertise in topics such as perception and what people think or mean by using certain words. I am also interested in photography but by no means an expert. That being said I would like to join this discussion and offer some thoughts.

The term normal lens as I understand it comes from the idea that the image produced is roughly equivalent to what a human would see with their own eyes. When the majority of people engaging in photography were likely to use standard film and a SLR in what was usually referred to as 35 mm film then a lens with a focal length of about 50mm would produce an image that was called normal, meaning about what one would see with their eyes.

Lenses with shorter focal lengths produce an image that has a wider field of view than that normal human view and the lenses then are referred to as wide angle. What we typically call telephoto lenses are producing an image that has a narrower field of view but I don't recall ever hearing them referred to as narrow angle lenses.

When digital SLRs were developed the size of the sensor was different from the size of the piece of film typically exposed in an image so the same focal length lens in combination with the different size sensor produces a different angel of view. This difference is described as the crop factor. The same lens would produce a different image on a different camera with a different size sensor or film.

The point is that terms like wide angle, normal, and telephoto really refer to this angle of view not the lens itself. The focal length of a lens is a physical property of the lens. The description of any lens gives an approximate number for the focal length, but I suspect that if we had a physicist do careful measurements we would learn what the rounding error is for any particular lens.

Some people say the lens should be labeled with it's effective focal length. This seems to be more confusing then helpful since it would have to be based on a comparison. Thus they would have to say this 50mm lens is effectively a 75mm lens on a camera with a 1.5 crop factor but if you use it on a camera with a 1.0 crop factor it is effectively a 50mm lens.

Those of us who spent some time with older 35mm film SLRs may need to rethink what normal means on our newer digital cameras. Normal is still an approximation of what a human would see. On the other hand it would be distinctly a narrow angle view for my dog. A dog's normal field of view would look like a wide angle view to humans.