Back in the 70s (when having a big bushy mustache wasn't ironic), the standard kit of most budding photographers included a SLR without the "D" mated with a fast 50. It was F2.0 if you were on a budget, F1.7 if you ate cheese sandwiches for a week, and an F1.4 if you just got that big promotion.* With some change rattling in your piggy bank, you'd save up for a moderate wide around 28mm and a short telephoto of around 105mm and Bob was your uncle.** The fast 50–the normal–got the hardest workout, as it was pretty close to your actual vision and useful in a lot of situations.
Jump in a time machine to the year 2013. A coffee costs more than a whole meal back then, and most cameras are sold with a zoom. But even now there are those that keep the faith with prime lenses, valued for their size, speed (a slow zoom can be small, but a fast zoom is typically a monstrosity), and this thing that many call "shooting discipline", "favorite focal length" or something like that. The idea is that many photographers have a focal length that they feel the most comfortable with and that for whatever reason feels "right". For street shooters, that's often a 28mm or 35mm - wide enough to capture an environmental candidate, and also useful indoors when you can't always step back another five feet.
Meanwhile 50mm has also fallen into disfavor in some circles because it's no longer a "normal" on APS-C and Micro Four-Thirds cameras but rather a short telephoto that makes it far less useful for everyday. And for many using non full-frame cameras, even lenses that have a similar field of view to 50mm (i.e., 35mm on APS-C and 25mm on Micro Four-Thirds) aren't universally cherished or admired. The PanLeica 25mm has its fans, but it just seems like other prime focal lengths are in favor these days.
Which is interesting, because I've been down a similar road. For quite some time, my Pentax DA21mm F3.2 (~32mm EQ) was my most-used lens, and I've recently acquired a Panasonic LX7; the 24mm wide was a key factor. But I've also been re-acquainting myself with 50mm EQ and find something comforting and familiar yet at the same time challenging. 50mm EQ or thereabouts is literally the way we see the world, so framing a shot is instinctive. And as with any single prime shooting, it's a fun challenge to tell a story through a single focal length.
What you see here in the photo are what I'd like to call The New Normals. Each is approximately 50mm EQ (some more approximate than others) but each achieves it in a different way. None of the sensors are full frame, and each has its own strengths and weaknesses.
Pentax K-01 with FA 31mm F1.8This setup is the hammer. Literally. Both body and lens are so heavy and solid that you could drive nails with them. IQ is tops of this trio, with the highly coveted FA31 mated to a very good 16 megapickle APS-C Sony sensor. FWIW, the lens is more expensive than the body, and in my opinion, that's the way it should be. Contrast Detect AF is tack sharp for immobile objects, but struggles with movement. Still, manual focus (the FA31 has a nice long damped focus throw) with Focus Peaking is really nice, fast and silent.
Nikon 1 V1 with 18.5mm F1.8The speed demon. In good light, this combo AFs faster than any other mirrorless system, tracking objects without breaking a sweat. High speed RAW shooting (up to 10FPS continuous until the card is full) and silent electronic shutter makes this a great candidate for street, which, regrettably, I've yet to do. Watch this space. AF slows down in low light, but still workable. It had better be, since the lens doesn't have a focus ring. Metering of the V1 is really good though, so if you're willing to use this as a "Set and Forget" automated camera, it will deliver. And it's the only camera in this set to have an EVF, which is useful in bright light.
Pentax Q with 8.5mm F1.9The Minox. So small and unobtrusive that people barely notice it. So small that a wrist strap seems like overkill - I use a pinky strap. So small that it can dangle from your neck all day without requiring a follow-up visit to the chiropractor. Leaf shutter is whisper quiet. Controls just like a DSLR make it easy to adjust settings. AF good for static and slow moving scenes, a crapshoot otherwise. Manual focus + focus peaking + focus zoom works but doesn't feel as fluid as the K-01/FA31 due to the non-mechanical focus ring. IQ lags the other two but surprisingly good in good light.
So there you have it, the New Normals for a new era. What's your new normal?
* We won't even talk about exotica like F1.2, as that was like owning a Lamborghini. Mike Johnston at The Online Photographer has a much more articulate description of the evolution of fast 50s:
**Bob may or may not have been your uncle. What we are using here is an old phrase suggesting that things were good and hunky dory and you were happy with your kit.