Lens Factors: Prime Vs. Zoom Revisited

The great lens debate:  Fixed focal length primes vs. zoom lenses.  Which is better?  This is not a new topic, you could do a Google search on it right now and you’d find no less than 50 articles on it.   But with few exceptions, they would all be misleading, or at least a little dated.  Technology has improved, lenses have gotten better and a lot of what we knew a few years ago is no longer relevant.  So I’m going to take this opportunity to update the information surrounding the debate.

As an aside:  It’s very easy to believe that a current article posted somewhere on the internet is going to have the most current information.  Unfortunately, in truth, that information may have been regurgitated from another source.  And since the internet is so accessible and everyone can write in whatever forum they have, it’s very easy for that information to perpetuate.  I’m not saying the information and wisdom is bad, just that it might be a bit dated.  Each of these misconceptions may have been 100% at one time, but technology has improved and time has passed and the line between black and white has gotten a little wider, a little grayer and a little less defined.

Old Wisdom:  Primes Are Sharper

When zoom lenses first came on the market, the only real advantage that they had was that they were convenient.  They were loved by the consumer for that reason.  But the professionals shunned them because they weren’t sharp.  The edges tended to ghost and distort and focus beyond the center was limited.  The industry has come a long way and zoom lenses have grown more complicated and a lot sharper.  Many zoom lenses on the market have great edge-to-edge sharpness throughout it’s entire focal length.  That’s not to say that every zoom lens is perfect.  Many of the entry-level zoom lenses still suffer in the edge-to-edge sharpness, but they still tend to be pretty good.  At least they aren’t nearly as bad as the old wisdom might lead you to believe.  The best and sharpest zoom lenses are still the ones with the shorter range of focal lengths.  But I may be writing about that fact as old wisdom in a few years, because that margin is getting smaller and smaller.

Now the flip side.  It’s true that prime lenses tend to be pretty sharp from edge to edge.  But it’s not like technology has really improved the prime much over the years.  Sadly, in an effort to lower costs to compete in the market, some lens manufacturers have relaxed their standards so that their entry-level prime lenses give primes a bad name.

Old Wisdom:  Primes Are Cheaper

Prime lenses are much simpler in design as the only moving parts are tied to the focusing mechanism.  Zoom lenses need to balance both focusing and zooming mechanisms, and so they tend to be quite complicated with multiple moving lens groups and elements.  As one would expect, more complicated design and construction results in higher costs.  Of course by now, after a few decades of working with and refining their lenses, manufacturers have really perfected their mechanics and they’ve streamlined the whole process.  So the prices, in general, have come down on Zoom Lenses.  On a lens-to-lens comparison, the prime is still going to be cheaper.  But if you consider the lenses that the zoom might replace, the zoom can take the title in this category.  For example: A 24-70mm zoom – some of the best zooms on the market – can easily replace two or three lenses in your bag.  So even though that zoom is going to be quite expensive, in the long run, it probably ends up being more economical than the three lenses you would otherwise need.

Misconception:  Primes Improve Skill Development

This one is a bit of a pet peeve.  The theory is that prime lenses make you a better photographer.  Somehow, having a zoom lens makes you lazy and helps you to avoid having to plan your shot.  I’ve heard the expression “zoom with your feet” thrown around about how primes are allegedly superior to zoom lenses.  But that’s all propaganda  in my opinion.  In truth, I believe that if you’re a lazy photographer, prime lenses aren’t going to fix that.  Speaking from a technical point of view, a change in focal length changes the angle of view and in turn the perspective.  So unless you’re changing your physical position, you’re not necessarily getting the most flattering perspective for the shot.  That’s true with zooms – and I wrote about this in the past – but it’s inversely true of prime lenses.  Suppose you’re changing your position because your prime lens is limiting how you want to frame the shot.  Well that sounds a little backwards to me.  Because you should be considering your position and perspective first, and then selecting the most appropriate focal length.  With zoom, that’s a twist of the wrist.  With primes, you’re changing the lens.  There’s no excuse for laziness.  It’s something you need to get past mentally, and your equipment will not change that.  If you really want skill development, teach yourself to think about your shot independent of the camera and the lens:  Visualize the shot as you would like it and then plug in the details that get you there.

Final Thoughts

It’s probably painfully obvious that I wrote this article as a proponent for zoom lenses.  I just feel that modern zoom lenses have not gotten the attention and respect that they deserve.  Now I will admit that there are still situations where you’d want to have some prime lenses.  I have a few myself.  A nice and fast 35mm or 50mm prime with a wide aperture such as f/1.4 or f/1.2 is not going to be beat by a zoom at that specific focal length.  But the lens I use most is a zoom.  And there’s no reason why your favorite lens couldn’t also be a zoom.