Why the Canon 50mm f/1.8 STM is the Only 50mm You Need

Every photographer needs a 50mm in their setup. Your life will never be complete until you do have one nestling in your bag. It’s the best focal length to learn and hone your skills with and could be the only lens you will ever need to use.

There are far more expensive options and there are much cheaper options. Regardless of the price, the new Canon 50mm f/1.8 STM is not just a good choice but, in my opinion, is the best choice for the EOS-mount.

Metal mount – no more toying around

With a slick new plastic barrel and metal mount, it feels like you’re getting a proper lens for the money. At a little over $100 US or a tad under 100 quid for Brits, you’re actually getting a proper lens now as opposed to the cheap plastic shell and crap-plastic-tastic mount of the old 50mm f/1.8 that felt more like a Lomo lens than something from Canon.

It’s black and white so it must be a street photo

It feels better than the 50mm f/1.4 USM but of course not as brick outhouse-like as the f/1.2L. Mind you, the L lens does weigh as much as brick, coming in just shy of 600g compared to the 159g f/1.8 STM. The L lens does have weather sealing but with that kind of weight, you’re most likely going to leave the f/1.2 at home most of the time.

From a practical point of view, there is no need for something like the f/1.2L. It does have a rather large maximum aperture but that comes at the expense of having both of your arms pulled out of your socket from the sheer weight of a chunky piece of glass attached to a DSLR. You don’t need a fast lens anyway, seeing as most DSLRs have amazing high ISO performance these days. Well, maybe not the 5Ds and 5Ds R.

Chinese mime artists are rubbish

Of course, Bokeh Bitches love fast lenses—I can’t get enough of them. If I still owned my Canon gear (yes, I had 5D Mark III with L lenses) a 50mm f/1.2L would definitely be in my dry box. But it wouldn’t come out all that often. It is a special lens but it is a lens for special uses—it’s something that you’d use to shoot at f/1.2 because you can not because you need to. If I want to go out to shoot street photos, I would happily take the 50mm f/1.8. And I always find myself taking the best shots with the f/1.8. Why? It’s light, so I hang around for longer, am pulling the camera to my eye more often, I’m encouraged to hunt around for shots and the focus is quicker so I get more keepers.

The Canon 50mm f/1.8 STM is…erm…reliable

The f/1.2L is a hoot, a real blast; it’s pornography vs the reliable consistency of the f/1.8. The f/1.2L is for the moments that you want to have a saucy bit of self-indulgence. The f/1.2L is jewellery for your camera that will attract acknowledging glances amongst other gear perverts. But just you try and hang a 5D Mark III with one of these attached to it for half a day and you will feel like your neck has been violated by a silverback gorilla. Maybe.

The 50mm f/1.8 STM is as sharp as you’ll really need

This might imply that the f/1.8 STM is a bit dull or inferior, optically, but that is far from the case. It’s a bit soft in the corners wide-open and has a bit of spherical aberration but that is the case with the f/1.4. This is where the f/1.2L shines, performing really well wide-open but the f/1.8 STM is fantastic from between f/2.8-f/4.

Canon has seemingly been egged on by YongNuo to do better with the number of aperture blades too, with 7 rounded aperture blades in the new STM version compared to the 5 blades in the old version. You can see the difference when you look at the bokeh balls—they start to look pentagon-shaped with the old lens, while they still look round at even smaller apertures using the new lens.

Gloriously round bokeh ball goodness – f/1.8 STM @ f/3.2
Bokeh balls worse than a YongNuo – f/1.8 II @ f/2.8

Mind you, the 50mm STM does have one aperture blade less than the f/1.4 and f/1.2L. But that’s not necessarily a bad thing: having an odd-numbered amount of blades is good for sunstars because they double the amount of pointy bits of light compared to a lens with an even-numbered amount of blades, which give you the same amount of pointy bits as there are blades. More pointy rays of lights tend to look better.

Sunstar example from Flickr user Anita Ritenour

You’ll get more blurry bokeh goodness with the f/1.2L but if all you care about is the blurry bits then you can get 10cm closer—closest focusing distance is 35cm vs 45cm of the f/1.4 and f/1.2L—to your subject, forget what your subject looks like when they’re 10cm closer to the camera and get more blurry bits.

I’ll admit that there have been many times when I have reached for the f/1.2L over the f/1.4 or f/1.8, and there will be many times that I will choose to indulge in a bit of bokeh whoring at the expense of a not-so-practical setup. But if I had to choose one lens to have permanently stuck to a Canon full frame DSLR to use, from a purely logical point of view, the 50mm f/1.8 STM would be the one that I would go for.

Watch the DigitalRev TV review of the Canon 50mm f/1.8 STM here.

Can’t think of a caption, although the image is pretty self-explanatory

The Specs

50mm f/1.8 STM 50mm f/1.4 USM 50mm f/1.2L
Optics 6 Elements / 5 Groups 7 Elements / 6 Groups 8 Elements / 6 Groups (1 Glass Moulded Aspherical)
Aperture Blades 7 Rounded Blades 8 Blades 8 Blades
Close Focus 0.35m 0.45m 0.45m
Filter Size 49mm 58mm 72mm
Weight 159g 268g 591g

Sunstar photo from Flickr user Anita Ritenour