At the most basic level, all camera lenses can be sorted into two groups: zooms and primes. Zoom lenses do just what you think, twist a ring (or hit a button) and they zoom in or out, changing how much of the scene you see. Prime lenses, on the other hand, are fixed, unable to zoom in or out, and just display one set level of magnification.
You might be thinking "Well, it sounds like I should just get a zoom lens for the added flexibility," but that would be false. Or at least mostly false. To be sure, some zooms rule, lenses like Canon's 28-70 f/2 and Nikon's 70-200 f/2.8 are wonders of optical engineering, but they're also absurdly expensive, absurdly heavy and absurdly big.
Prime lenses, on the other hand, are relatively simple. There are no complex helicoids and significantly fewer glass elements, so this means that primes can be cheaper, lighter, and better — all at the same time. To get 50mm at f/2 with that Canon zoom above will cost you $3,000, to get 50mm at f/2 with a Canon prime will cost you $150. The image quality will be basically indistinguishable. That's insane.
To avoid getting further worked up about how great of a deal prime lenses are, I'll summarize: the absolute best quality-per-dollar investment you can make into any camera system is a prime lens, but which one?
A Quick Primer on "35mm Equivalent"
The idea of "35mm" or "full frame" equivalent is needlessly confusing and annoying, but it's really the only way to talk about similar shooting experiences over cameras with different sensor sizes. You'll sometimes see this referred to as "crop factor". So, a quick table of lenses that will provide (nearly) the same shooting experience, depending on your camera's sensor size:
From here on out in the article, I'll just be using the "full frame equivalent" numbers.
The so-called "normal" range of prime lenses consists of 28mm, 35mm and 50mm. All three are great, all three offer distinct feelings and it does ultimately come down to personal choice. As you might expect, 28mm offers a lot more of the "scene," where 50mm gets in quite a bit and feels a lot "tighter." 35mm is a happy medium.
A quick test to see which one you might like the best is to break out your phone. The following numbers are based on any of the modern multi-lens iPhones or Android phones that generally share similar focal lengths.
Luckily, these things are relatively cheap — and hold their value well enough — that you can feel free to experiment.
So you've decided which focal length you want and which camera system you need it for. Which one should you get? Our general advice on the budget end is to stick with buying lenses by the camera manufacturer, on the high end there are some nice savings to be had by buying 3rd party (Sigma "Art"-line primes in particular), but you ultimately can't go wrong sticking to the camera manufacturer.
Below we've assembled our picks for "budget" and "upgrade" prime lenses for each of the major camera systems.
Fujifilm X-Mount
In a lot of ways, Fujifilm is the easiest of these lists to assemble. Fuji's lenses are awesome, affordable and cleanly divided across lower and higher price points. The advantage of plunking down the extra bucks? You'll get a faster max aperture (better in lower light, more background blur) and slightly better optical/build quality, but you'll also gain some extra weight in the lens and lose some extra weight in your wallet).
28mm Equivalent
35mm Equivalent
50mm Equivalent
Canon RF Mount
Canon's RF lens lineup is pretty young, so it doesn't have the bajillion options that its EF line does. Keep in mind you can always buy a great used EF prime and throw one of Canon's EF/R adapters on it. This is where "35mm equivalent" starts getting annoying. If you've got a full frame camera like an R5 or R6, take these recommendations at face value. If you've got one of Canon's APS-C offerings like the R7 or R10, refer to the chart above (but generally think 28/35/50 = 16/24/35). Note: Canon refuses to make a 28mm lens for some reason.
24mm/28mm
35mm
50mm
Nikon Z Series Mount
Nikon's Z mount is similar to Canon's RF mount in that it's pretty young and options are fairly limited (for now). Luckily, it's the same deal with the FTZ adapter. It's $150 more expensive than Canon's, but the lenses are overall cheaper.
28mm
35mm
50mm
Sony E-Mount
Sony's EF lens ecosystem is by far the most mature/diverse mirrorless lens system. Which is great news for us! No adapters needed and plenty of choice.
28mm
35mm
50mm
