Does lenses zoom affect aperture limit? When using my 18-55mm lense in manual mode the aperture automatically changes based on my lense length. For example if I have it at 55mm the lowest aperture I can set is 5.6, 35mm is 4.5, & 18mm is 3.5. I can set it to anything above these but the lowest seems to be restricted based on zoom.. Is this correct or am I doing something wrong?
Is aperture limited by lense zoom?
- Thread starter MarilynS
- Start date
It is largely an issue of price and design. More expensive lenses are designed to adjust to hold a constant maximum f/number as they zoom. But an $200 lens will take liberties that a $1400 lens will not.
18-55mm for $200 is f/3.5-5.6 maximum, varying with zoom
17-55mm for $1400 is always f/2.8 maximum at any zoom.
Bob Blaylock
Senior Member
I think it has a lot to do with the rise of ever-sophisticated and automated cameras.
Can you imagine having a 1970s-vintage all-manual camera, and trying to make sense of a zoom lens whose aperture settings change according to the focal length? I think it'd be nearly impossible., and for that reason, I think that if such variable-aperture zooms existed, then, they must have been extremely rare. Such lenses are really only feasible, today, because of the sophisticated degree of communication that now exists between them and the camera to which they are mounted.
RocketCowboy
Senior Member
Howdy Marilyn and welcome to Nikonites! Wayne and Joe both answered your question already, but I still wanted to welcome you here.
Well, usually not much factor at f/8.
It could be one more thing to keep up with, but we had fewer things to worry with back then.I guess I think it is about lens design. Zooms were just starting to be casually accepted in 1970 (but not for serious purposes yet), and there were only a few of them. A couple of Nikons were constant aperture, but the state of the art then was not high, and these did this then by limiting zoom to moving only one group of glass. There were a couple of others that zoomed two or more groups, which were better corrected for sharpness, but aperture varied with zoom. Esp for zooms, design was very difficult before computers to do it.
But... we've come a long way in 45 years. My opinion is that todays $1600 - $2000 f/2.8 zooms are optically as good as primes. Costly maybe, but very convenient, and impressively good.
Bob Blaylock
Senior Member
Well, usually not much factor at f/8.
I guess I think it is about lens design. Zooms were just starting to be casually accepted in 1970 (but not for serious purposes yet), and there were only a few of them. A couple of Nikons were constant aperture, but the state of the art then was not high, and these did this then by limiting zoom to moving only one group of glass. There were a couple of others that zoomed two or more groups, which were better corrected for sharpness, but aperture varied with zoom. Esp for zooms, design was very difficult before computers to do it.
But... we've come a long way in 45 years. My opinion is that todays $1600 - $2000 f/2.8 zooms are optically as good as primes. Costly maybe, but very convenient, and impressively good.
Yes, primes were much more dominant then. Any 35mm SLR usually had, as its “standard lens”, a 50mm prime lens. Zooms did exist, but they weren't so common, and were generally not regarded as being comparable in quality to primes.
The one example I have is a Vivitar 85-205mm ƒ/3.8 zoom lens, made some time in the late 1960s or early 1970s, that I originally bought to use with my F2. It's actually pretty sharp at smaller aperture settings, perhaps as much so as the stock 18-55mm that came with my D3200, or of my two prime lenses that are also from the 1970s; but at wider aperture settings, it has some rather interesting aberrations and distortions. It's probably not atypical of zoom lenses from its period in time. See my thread at this link for more about this lens and its optical traits.
The 18-55 that came with my D3200 may not be quite up to the quality of my two 1970s-vintage primes, but it's noticeably better across most of its range than my old Vivitar is across most of its range.