People don't seem to understand lenses (moving beyond 'zooms vs primes' thinking)

[kye]

I've been thinking about lenses a lot over the last few years, and just to be cheeky I've put some observations into a framework.

Level 1 is where we start - with zooms

The normal start to using lenses is with zoom lenses, probably the kit lens.

We know the thinking at this stage: its convenient, you stand in one place and zoom, hooray!

Level 2 is what most YT lens videos are about - primes are better than zooms

We all know the arguments.  Primes make you "zoom with your feet", they make you learn about perspective, they're sharper, better in low-light, BOKEH!!!!1, you can learn the FOV and develop an instinct for it, vintage ones are cheap, "real photographers / cinematographers use primes!"

There are approximately 1000 billion videos and tutorials explaining this, but this seems to be where the thinking stops.  I've not seen that much stuff that goes beyond this, but this is really just the start.

Level 3 is where understanding begins - zooms and primes have their uses

Almost none of the discussion up until this point acknowledges that lenses create images, and images have aesthetics, and aesthetics are what is actually being discussed.

Moving to talk about motion pictures now, and cinema especially, there is a bunch of nuance that Level 2 doesn't really discuss.

People have decided that FF sensors are the most 'cinematic' and typically are used with FF vintage lenses.  This means that the FOVs are 24mm / 28 / 35 / 50 / 85 / 100 etc, with maybe a 40mm in there if you're getting fancy.
These weren't the FOVs of cinema though, because cinema was S35.  So the FOVs of cinema using the 50/40/35/27/18 were really like 75mm/60mm/52.5mm/40.5mm/27mm.
It gets stranger when you add anamorphic into the mix.  If I go to B&H anamorphic cinema lens category and sort by best sellers, we get:
 - DZOFilm Arcana Anamorphic Prime 3-Lens Kit, which are FF and 32/45/75mm and 1.5x, so on FF they are: 21mm 30mm and 50mm
 - BLAZAR LENS Talon 50mm T2.1 1.5x, which is FF and equivalent to a 33mm
 - Sirui Saturn 35mm T2.9 1.6x which is FF and equivalent to 22mm

If you're using the standard FF lenses on a FF camera, you are using the FOVs that stills photographers used, rather than those that cinematographers used.

Shooting on S35 sensor size (or crop mode) with FF lenses can create some of these in-between FOVs too.

People at Level 2 thinking probably won't be swayed by the above.  I would imagine the thinking is take a step forward or back, what's the difference?

Level 4 is where understanding begins to mature - enter the feedback loop

The feedback loop is where you realise that the focal length changes how you shoot.

A ridiculous example to illustrate it.  You decide to shoot on only a 28mm on a FF camera, but when you frame up a close-up shot, the distortion makes the talent look awful, so you take a step back and now the footage feels more distant because we're not seeing the talents face so much because there are no close-ups.  

We all know about perspective from level 2 thinking, but the level 3 thinking was that taking a step forward or back was no big deal, so which is it?  This stuff is subtle, but (like all feedback loops) it pushes us to act differently and this can create a cascade of changes over time.

Level 4 thinking realises that this dynamic is powerful and pervasive.

I shoot in public, so I don't control the environment.  I discovered that if I shoot with a 35mm FOV then I can get environmental portraits of my friends and family from close enough that people won't walk in-between me and them, but moving beyond a 45mm I'd either get shots of them that were tight and didn't really show their environment that well, or I'd step back and be struggling with people walking in-between me and the subject, which is a completely different situation.  How would I respond to this?  I might shoot from eye-level instead of chest height.
Now I've changed the shot angle because of a FOV change.  
If I shot from eye-level for a while I might notice that I get more attention and now I find that the people interacting with my subject are more aware they're being filmed and keep looking at the camera.
Now my subjects are acting differently because of a FOV change.

If I asked someone the difference between shooting with a 35mm and 45mm would they think it would change the shot angle and subject behaviour?  Not with the Level 2 thinking of "primes are sharper! duh!!", or the Level 3 thinking of "just take a step back! duh!!".

What about controlled sets?  
Sure, on a controlled set there aren't random people walking in-front of the camera, but now we're talking about actors and all the dynamics that goes on there.  
Can great actors deliver amazing performances while the matte-box is only inches from their face?  Sure.  Do YOU have actors that are that good?  I don't think so.
Can great production designers change a set to accommodate a camera being further away, while keeping the frame looking the same?  We know that as we move the camera back the subject gets smaller in frame, and that as we do that the background gets smaller but not nearly as fast as the subject does.  This is great if you are only filming the subject and don't really pay attention to the composition of the entire frame.  But you're a talented cinematographer, so you want to move back a bit and keep the same composition, which means that production design needs to 'cheat the camera' and basically rearrange every item in frame that isn't in the very background.  I remember shooting a student film in a cafe and every setup required moving the vase of flowers on the table the subject was sitting at.  That vase probably used two-thirds of the area of the table!

I watched a video recently where a street photographer tested a 40mm prime for the first time.  They didn't know what to make of it, having only a week to shoot with it before they had to release their video review.  What struck me wasn't that they didn't know what shooting with a 40mm was like, it was that they didn't seem to understand that there's a period of learning that goes on, they didn't understand that the feedback loop exists.  
I realised they had 'learned' each focal length by memorising its attributes (which Level 2 photographers will crap on at great length about), rather than having learned them for himself by following a process where you explore the feedback loop and see how it makes you feel and how it makes you act and how the world responds to that, and how you respond in turn, and how the loop feels and matures over time, and how to make the loop go faster etc.

I recently spent some time in a small town in rural Japan and shot the same location with FOVs equivalent to 71mm, 82mm, and 100mm.  I went out for a walk each night with one of those lenses, going out for perhaps an hour or two.  Shots that were possible with one were not with the next, shots that were great with one were lifeless with another.  As I walked down the same road from my accommodation seeing the same shots night-after-night and making different framing decisions with each lens (and deciding to take the shot or not to bother as it didn't work) I noticed that I made different decisions to walk one way or another as certain subjects required different FOVs and distances to make them.
I've also spend a lot of time, over several trips, shooting night scenes with 68mm and 71mm FOVs.  In some locations I can make some shots and not others, while in other locations I can take different shots.  If I'm shooting across a road then the width of that road (combined with my FOV) determines the type of shots I can take.  After taking a number of those types of shots I start to adapt to how I'm shooting these locations.  The more I shoot the more everything feels different.  Level 3 thinking says "just take a step back, what's the difference?" and when shooting in those situations the difference between a 35mm and a 50mm feels like it's a span where there are several complete aesthetics in-between the 35mm end and the 50mm end.  Thinking about shooting a 50mm FOV vs an 85mm FOV feels like travelling to a different country where things look similar but feel very different in practice.

I know I'm barely scratching the surface of Level 4, and perhaps there are levels beyond this that I'm unaware of, but it's just amazing to me that almost no-one seems to talk about anything beyond Level 2.  It's probably controversial to say, but I deliberately avoid almost all stills-only people because the thinking seems so rudimentary in comparison to people who shoot moving images.  You can feel the limited thinking and the "well, actually!!!!" responses where they miss the entire point entirely because one lens is sharper or something ridiculous.

Anyway, hopefully this helps.  I've not really heard anyone talk about this stuff, which seems a shame as the rabbit hole is very deep and to only talk about ankle-deep water seems silly.