In my older film days, everyone used prime lenses (lenses of a single focal length) because either zoom lenses were not available, or they were of fairly poor quality (as zoom lenses were in those days). However, technology always advances and, nowadays, zoom lenses (the good ones) are as good, if not better, in optical quality than many prime lenses. Zoom lenses also provide great flexibility and versatility, because you effectively have many prime lenses in the one lens. That said, many internet professional-amateur photographers vehemently disparage zoom lenses because they don’t represent the purity of photography that they require, and which they believe can only be attained with prime lenses. I would suggest that view is debatable.
Whenever an internet forum discussion turns to zoom lenses, more than one professional-amateur photographer will pipe up and opine that a prime lens is much better and that one should learn to ‘zoom with your feet’. Zooming with your feet meaning that you should walk backwards or forwards in order to frame your subject in the camera’s viewfinder. I assume that all of these photographers inhabit regions of the earth where there is unlimited space and no obstacles, cliffs, roadways or other impediments to ‘zooming with your feet’. Or maybe they only photograph subjects where it’s possible to move backwards and forwards the required distance. By now, I assume that you’ve gathered that I don’t subscribe to the ‘zoom with your feet’ practice as being the pinnacle of photographic purity, especially when it could mean ending up at the bottom of a 1000′ cliff.
Not only does zooming with your feet create some potential difficulties (or downright dangers), it also changes some aspects of what the camera sees, as perspective changes when you move backwards or forwards. Now this can be alleviated by having appropriate lenses so that perspective remains more or less the same as you move closer or further away from your subject, but it also means you need a number of lenses ranging from wide to telephoto in order to achieve this. It’s a bit like owning a zoom lens but in multiple parts, which then leads to further debate as to which lenses to own and carry around, and the worrisome aspect of gaps in your lens repertoire. Opinions from the professional-amateur photographers naturally will vary significantly, as they dissect the value of various lenses in millimetre focal length variations, f stops and brands. Sometimes a little perspective is in order.
The argument then often moves to one about cost, size, weight and speed (aperture), with the justification being that three or four prime lenses are cheaper, smaller, lighter and faster. You can have cheap, small, light or fast, but not all together, as nothing comes for free. An f2.8 zoom lens, for example, is only one and a bit stops slower than the typical f1.8 prime lens, which is not a lot, and the faster the lens, the more expensive, larger and heavier the lens becomes. While fast primes can provide some benefits in special circumstances (at an appreciable cost), I simply cannot accept that a bag full of prime lenses is somehow better than, for example, one zoom lens and perhaps a ‘special’ prime lens. Anything else, simply creates a lot of lens changing and even more zooming with your feet.
Finally, some throw down the gauntlet and avow that primes focus your vision, make you visualise the scene better, force you to work for your art and thus make you a better photographer. It’s a bit like the argument that you should use hand tools rather than power tools, as the former makes you a better craftsman. Seriously, a 35 mm prime lens has exactly the same field of view as 35 mm set on a zoom lens; the zoom lens just allows you to change, for example, from 25mm to 35mm a lot faster and easier. I should be careful, however, as them’s a fightin’ words and they could raise some awful storms in forum teacups, if word got around. And when a storm looms, there’s not much room in which to zoom with your feet, so best to take shelter.
Unfortunately, peer pressure abounds and many are coerced by well meaning and devout seekers of purity and, once that path is taken, it’s difficult to admit that things are anything but perfect. That may be your prime directive, but I prefer to just zoom about, as zooms come with a guaranteed no gap policy.