What I think about when I think about Focal Lengths
I realized that I really think about photography in terms of the classic focal lengths — 35 / 50 / 85 / 100 / 135. This article explains what I think about when I think about focal length.
35mm film / full frame equivalents are used throughout this article.
50mm
Also known as a “normal lens” — more on this later. I suppose it matches the central area of what the eye can focus on, or something like this — people say it mimics the way the eyes sees.
Maybe there’s some truth to this. If I’m about 3 to 5 feet (1–2 meters) away from someone — a nice comfortable distance — 50mm gives me a nice portrait orientation view of them that feels undistorted.
It feels personal, intimate — one person interacting with another person in a completely normal way. What I see of them is about what I would expect to see of them at that distance.
Henri Cartier-Bresson favored the 50mm field of view. He said of 90mm — “It cuts much of the foreground” and of 35mm “splendid when needed, but extremely difficult to use if you want precision in composition.”
[50mm] corresponds to a certain vision and at the same time has enough depth of focus. — Henri Cartier-Bresson
We tell every generation of photography students that 50mm should be their first lens — the “nifty fifty”. I met one photographer who had a 50mm on an APS-C camera — when I explained to her that it was really a 75mm equivalent, she said “That explains why I keep having to back up to take the photo I want.” If only she got a 50mm equivalent lens, she’d be happy.
I do think there’s something about the 50mm field of view that just feels natural. (“hold that thought.”)
35mm
I tend to think of 35mm as 50mm with “wings” — at the same distance, I turn the camera to landscape orientation, have roughly the same view of the person, but with a bit of the environment around them.
It’s also one of the classic focal lengths for street photography and reportage — it’s a photo of the guy coming out of the courthouse in handcuffs, with a cop on either side. It gives you the subject and the environment.
I love this focal length for events — since you’re mostly photographing people interacting with each other. It’s wide enough to give you a few people in a shot and a sense of the environment, but tight enough that you’re close to the action.
It is a beautiful lens at times when needed by what you see. But very often it is used by people who want to shout. Because you have a distortion, you have somebody in the foreground and it gives an effect. But I don’t like effects. — Henri Cartier Bresson
85mm (and 75mm)
At the same 4 or 5 feet (1–2 meters) away, I’m now taking a portrait — a photo of their face and shoulders with upper chest.
This focal length (and longer) is better for full body — you have to back up far enough that you’re no longer looking down at their legs, which makes the subject appear more normally proportioned than with a 50mm.
50mm isn’t good for full body in portrait orientation — you’re too close, you’re either looking up at their face or down at their feet, which makes their legs look short.
85mm is considered a classic focal length for portraits — you’re far enough away to get a bit of perspective compression, but close enough for it to feel intimate.
For me, 75mm is the perfect short telephoto focal length — simply because my studio is only about 18 feet long and I can’t back up any more to get a full body shot.
100mm
Sort of more of the same — more extreme perspective distortion than with 85mm (I’ll explain what perspective distortion is in a bit).
I tend to think of this as the “high end clothing catalog look.” At this distance, you’re not looking down at the subject’s feet anymore when shooting full body. This focal length begins to impart a “larger than life” look — just a bit flattened, which leads to an unapproachable feeling. I suppose in some ways it’s a luxury focal length — you need to be able to afford the space to back up far enough to use it!
I also enjoy this focal length for taking pictures of the buildings in NYC — if a building is half a block away and the light is hitting it in an interesting way — 100mm is a good focal length to capture that. (75mm for taking photos of buildings feels a bit like how 35mm feels compared to 50mm — you get a bit more of the environment.)
Perspective Distortion
When something is further away, it appears to be flatter.
Create a “claw” with your hand, as if you’re holding an apple. Bring it so the thumb is as close to your eye as is comfortable — very close. Your thumb is abnormally large in relation to the rest of your hand.
Now hold this hand shape and bring your hand to full arm’s length — it now seems flat in comparison.
This is because the relative ratio has changed. If your thumb was 1 inch (3cm) away from your eye, and your pinky 4 inches (12cm)away, it was a 4:1 ratio.
When you bring your arm to its full length, your thumb is maybe 20 inches (51cm) away from your eye, and your pinky 24 inches (61 cm) away. This is a 5:6 ratio. As you get closer to 1:1 things appear more and more flat (1:1 would be completely flat — no difference between front and back).
This flattening of things that are far away is known as “perspective compression.”
You don’t normally notice this perspective compression because the object is farther from you. It’s not flat, it’s just far. But with telephoto lenses, you can artificially bring that object closer to you, so that flatness you’re normally not aware of is exaggerated because the object is seemingly brought closer to you — but it’s still as flat as it would be as if it was far away.
Some people get confused about this because the term is “distortion” — which is most often used in photography to discuss problems with lenses, but this is more to do with the way we perceive the world and the way photography can warp that perspective — which is half the fun of photography (for me anyway).
When the effect is to make far away objects appear flat, this is also known as “perspective compression” — perspective distortion being either close enough to exaggerate features (think of the door “peephole” effect), or far enough to flatten them.
Telephoto lenses — in addition to flattening, are flattering. They make noses look smaller, though they also bring the ears forward. To a point anyway, after a while the subject starts to look like a cardboard cutout. Most sitcoms are shot this way — 3 cameras to capture the action, each more than 20 feet away from the actors. The flattened effect serves to heighten the comedy.
135mm
Once you start getting to 135mm and longer, you get what I call the “storybook effect” — all of the layers of the image appear flattened, sort of like a children’s storybook. The subject is flattened, the things behind them are flattened, it starts to look more like an illustration than a photograph.
Take the photo to the left (or above on mobile). Look at the people in the background — it looks as if they’re in a line, all walking one after another, but it’s entirely possible that they were weren’t at all near each other. That’s perspective compression.
I first became aware of this focal length thanks to the “Russian Mother” who took photos of her children. In an interview she said she used a Nikon 135mm lens. While a lot of the magic of her photos is the subject matter & the post processing, she’s the reason I bought a 135mm lens — and I look forward to using it on a shoot to create this storybook feeling. (Though she also photoshops in background blur to heighten the effect.)
I also think of this look as the “Victoria’s Secret” or “Sports Illustrated Swimsuit” look — a storybook feel where the model is isolated on a tropical island. Not every SI/VS Swim photo is shot this way — and there’s really not much in the background besides water and sand, but if I had to guess, a 70–200mm f/2.8 lens is the most common lens on these shoots.
Beyond this are the super telephoto lenses — mostly used in nature photography. Next time you look at a photo of a tiger or a hummingbird, think about how flat those images feel. That’s extreme perspective compression.
28mm
This is the focal length of the Ricoh GR. I don’t tend to “think” in 28mm. I find it to be more subconscious in a way. I don’t think about “how am I going to compose this shot? — I simply shoot.
[28mm] simply matches the way I instinctively happen to see, and it also is fairly close to the natural field of view of human eyes when not focused on anything in particular. — Ming Thein
Often when I have my Ricoh GR (GRD series actually) camera, I hold it in my hand almost like it’s a cell phone — it’s completely unobtrusive. And when I use it, I don’t take any care to “compose” the shot — I simply point and shoot. Ricoh’s snap focus feature makes it great for taking spontaneous moments — you don’t even have to focus the camera, it’s just in focus.
I often don’t even have the rear LCD screen on, if I do turn it on, it’s because I want to compose — which means I have a moment. Often I don’t even stop walking, I just see something interesting and point and snap. It’s not until a later that I even bother to look at the photos.
Which is why I often say that I don’t think of my Ricoh as a camera I use to “take photos” — it’s there to document moments. Taking photos involves thought, effort at composition, etc. None of that happens when I use the Ricoh — it’s an extension of my eyes that happens to be attached to my arm.
This also is close to the focal length of most camera phones — the rear facing lens anyway (not the selfie lens). For cell phone manufacturers, it’s important that when you hand the camera to the waiter to take a photo of your whole table, everyone’s in the photo.
Among the only times I intentionally use this focal length is when photographing large bridal parties.
Of the few times I intentionally use 28mm — such as in the photo above — it’s as an even wider version of 35mm. An extreme environmental portrait. If 35mm was good for reportage (“the criminal in handcuffs and a cop on either side”) 28mm is even wider than that — the protester and the line of cops in the same photo. Often this focal length requires getting really close to the subject to get them to fill the frame, which can be uncomfortable.
For more on 28mm, see my review of the 7Artisans 28mm f/1.4 lens.
43mm — The Definition of Normal
Neither 35mm nor 50mm, 43mm seems an awkward focal length, but it happens to be the length of the diagonal of a piece of 35mm film. This would make 43mm the definition of “normal” lens. (by some definitions — more on focal length.)
The lens doesn’t have to “bend” the light much to make it reach the sensor, it just passes straight through. This means there are fewer elements, so they can make these very compact, and they tend to be very sharp with few (lens) distortions (or perspective ones). This is why you often find this focal length in “pancake” lenses — very small lenses.
This is the focal length stuck to the front of my Fuji X-Pro1 (27mm pancake lens, 43mm equivalent). A modern classic camera with a “classic” (if not often discussed) focal length.
On APS-C 27mm is normal (fits the diagonal). On Micro Four Thirds about 22mm is normal.
Now that we know that 43mm is the true normal lens, perhaps we can re-think why we like the 50mm field of view so much — it’s ever so slightly telephoto. My beloved 35mm on APS-C that I used for many years was the equivalent of 53mm. Perhaps the reason 50mm is so popular is that it feels normal — but ever so slightly enhanced.
Henri Cartier-Bresson probably single-handedly popularized the 50mm lens. Perhaps that and love of round numbers — 43mm or 57mm doesn’t sound as “standard” or “normal” as 50mm.
I wonder if the “magical” focal lengths where lenses tend to operate the best are magical because of their relationship to 43mm — the math for lens design becomes easier when the lenses are in easy multiples of 43mm, and before computer aided lens design, that could have meant a lot. Especially considering that you have to create machines to ground the glass to specific curves, and all those curves have to interact with each other precisely.
43 * 0.5 = 21.5mm (21mm)
43 * 0.66 = 28.38 (28mm)
43 * 0.8 = 34.4mm (35mm)
43 * 1.2 = 51.6 (52mm)
43 x 1.33 = 57mm
43 x 1.5 = 64.5mm (65mm)
43 x 2 = 86mm (85mm)
43 x 2.5 = 107.5mm (105mm)
43 x 3 = 129mm (130mm)
Perhaps someone more knowledgable than me can add some illumination to the subject.
Final Note on 43mm
On my Pentax K1000, the camera I learned photography on & the standard that I use to measure SLRs to this day (especially analog manual focus aids), the viewfinder has a 0.88x magnification which means at 50mm you get a 1:1 view of the world.
A little math and it seems that ~43mm would give you a 1:1 view of the world with 1.0x magnification.
The Epson R-D1 has a 1:1 viewfinder (1.0x magnification). When you put your eye up to the (rangefinder) viewfinder you can open both eyes and see the same scene.
The widest framelines are for 43mm (28mm on APS-C crop) and with the camera up to your eye, you struggle to see both the left and right framelines at once. Though if you drop the camera from your eye, you can see wider than the framelines.
Focal Length is literally the length of the focus. If you imagine a pinhole camera, the distance from the image plane (film) is the focal length.
This means that if you consider the diagonal length of film, 43mm is a perfect square — with the pinhole as far from the film as the film is wide (in the diagonal).
A “long” lens puts the pinhole further away — a smaller portion of the image is projected onto the film. A “wide” lens puts the pinhole closer.
Aspect Ratio — Micro Four Thirds & Medium Format
I own the Panasonic GM-1, which is the world’s smallest Micro Four Thirds (m43) camera. The only lens I ever use with it is the Panasonic 20mm f/1.7 — a pancake lens (well and some adapted lenses). (m43 has a 21.6mm diagonal, making this a normal lens.)
Most cameras (full frame, APS-C) are 2:3 aspect ratio, but Micro Four Thirds cameras are 4:3 aspect ratio. (Many Medium Format cameras are also 4:3 aspect ratio.)
What I find is that the 20mm lens on a m43 camera in portrait orientation feels like a 50mm lens, but you get a bit more of the of the sides. I was expecting it to feel more like a 35mm lens because people say “multiply by two to get the equivalent full frame focal length” — and that may be true if you strictly measure the diagonal, but when in portrait orientation, the height feels to me like a 50mm, and when in landscape orientation you don’t get quite as much width.
I like this combination for its Instagrammability — it acts as a normal lens, and it doesn’t need to be cropped for Instagram, so you can frame and post without cropping or adding a border to your image to match Instagram’s aspect ratio.
It’s also closer to the 8x10 print, and the 8.5x11 magazine page aspect ratio (or the A4 of European magazines). Which means that if I intend a photo of mine to be printed or published, I have to think about what will get cropped out when composing with my other cameras — but not on a 4:3 aspect ratio camera as only a very small amount has to be cropped.
However, if shooting in landscape mode, the 2:3 aspect ratio more closely mimics the 11x17 (8.5x11 across two pages) aspect ratio of a two page spread.
I don’t shoot micro four thirds anymore, but I’d consider it in a heartbeat if my purpose was to print or post on Instagram. Being able to envision the frame in the final destination format is invaluable. This is probably why so many Instagram bloggers are sponsored by Olympus.
Of note — I own quite a few photographic retrospective books, and many of them are 8x12 size — a 2:3 aspect ratio. Books by photographers for photographers are often in 2:3 aspect ratio. This doesn’t make 2:3 superior, it just means that the photographer publishes the book with the intent of keeping the original framing.
Final Thoughts
I happen to own a lot of lenses — 3 or 4 at 100mm, 2 or 3 at 85mm, probably 6 or more at 50mm, at least 4 at 35mm. But I’m not an engineer. So this isn’t a discussion of the technical aspects of lenses (except where I briefly touch on it — perhaps in an overly simplistic way).
Instead this is intended to be a guide for one of the questions I often see in forums. “I own a Fuji X-100, should I get a Ricoh GR?” — and the most common response I get when I try to explain why, despite not liking 28mm “for photography” — I still carry one every day.
In resolving that contradiction — why 28mm feels different from 35mm — I realized that each focal length has a personality, and I’m very much aware of that personality. That I’ve put a lot of thought into what that personality is — and that maybe someone out there would benefit from my version of that.
Your experience may be completely different from mine — and that’s great. It is, after all, art and it’s about how we each see the world, and how the equipment we use changes how we see the world, and how we choose the equipment that reflects how we want to express our vision.
Oh and because Tim said I should put a table in with a summary, here it is.
- 28mm — “really wide” — mimics the field of view of the human eye (maybe).
- 35mm — “wide” — I like this for event photography.
- 43mm — “true normal” — fits the diagonal of a piece of film.
- 50mm — “normal” — I like this for intimate naturalistic feeling portraits.
- 85mm — “short telephoto” — I like this for head & shoulders portraits, and full-body shots.
- 100mm — “telephoto” —Imparts a luxurious feel, but you have to back up further.
- 135mm — “long telephoto” — Imparts a “storybook” quality by flattening everything.
- 200mm — “super telephoto” — Beyond this mostly for sports & wildlife photography.
(The terms in quotes are approximate and may not match your textbook terms.)
To get the “full frame equivalent” on APS-C the rule of thumb is “multiply by 1.5” — for micro four thirds “multiply by 2” — for APS-H “multiply by 1.3”.
Further Reading
What is a Normal Lens — 35mm, 50mm, 43mm — compared to the human eye.
