Sunny-16, Zone Focus & Street Photography

Taking pictures is as popular today as it's always been, quite possibly more so with the upsurge in social media. Most people are happy with using smartphones day to day but there will always be a more serious or enthusiastic bunch who prefer to use an actual camera.

Most people will be using modern digital cameras, either DSLR or Mirrorless type. Manufacturers seem to be favouring smaller, mirrorless types at the moment with high-resolution CMOS sensors. A few will be using 35mm film cameras, most of which will be quite old. With a recent awakening to all things 'retro', people are dusting off their old film cameras. I regularly see students wandering around Bristol, shooting film and enjoying old-school photography which is nice.

I really enjoy back to basics, manual photography which is why I use Leica rangefinder cameras and manual focus, prime lenses. I'd be lying if I didn't admit to being slightly 'irked' by the way modern smartphones are practically 'weaponised' with camera technology. I rarely if ever use my phone camera, but I do accept that there is a justifiable link between your camera and your smartphone. Hold that thought for a moment.

One thing we don't have to worry about anymore is getting the right exposure for our pictures. Long since automated in our digital cameras and managed flawlessly on smartphones.

Who thinks about calculating the right exposure when taking a picture these days? If they do, there are even fewer who do this before even aiming the camera?

Well, you might think differently if you ever use an old film camera, especially if it doesn't have a light meter. Perhaps it does have one but is being very old, doesn't work very well, or at all. Such was the case when fell in love with a 1967 Silver Leica M4 in the shop window of LCE Bristol. 

My 1967 Leica M4 fitted with a 40mm f2 Summicron - No light meter, No worries !

The M4 doesn't have a built-in light meter. You can of course use it with an external hand-held meter. Leica make beautiful cameras but in my opinion also have a history of ugly, but practical, bolt on accessories. Case in point, this camera came with a bolt on selenium powered 'Leicameter'. A hideous looking contraption which attaches to the top of the camera and engages with the shutter control dial.  

I love the form factor of the M4, just as it is, perfect. It looks and feels very familiar being an 'M' model, robust, mechanical and well-made but lighter than my digital M’s. However, that awful contraption on the top just wasn't doing it for me and had to come off straight away, it never even left the shop with me as I could never imagine wanting to use it. I'd read up using the M4, watched a few YouTube videos and learned of the 'Sunny-16' rule which came highly recommended. It sounded like the answer to all my problems and the way to enjoy my film camera.

Sunny-16 is just a simple rule set, derived back in the days of film which sets out how to expose correctly for any condition. The rule still works today and is brilliantly useful. 

The rule simply states: 

In bright sunny conditions with hard shadows, with your aperture set to f16, your shutter speed will be the reciprocal of your film speed (or ISO setting). 

So, if you’re using 400 speed film, or ISO400 on a digital camera, your shutter speed will be 1/400s. 

For the observant among you, many old cameras (including the M4) don’t have 1/400s selectable on the shutter speed dial. They do have 1/500s though which is actually close enough. Film is more forgiving than digital for getting the exposure slightly out, and this really is, close enough despite being seemingly 25% over the ideal value.

But what if it’s not sunny? … the rule continues:

• If it’s mildly overcast and shadows are visible but with soft edges, use f11.

• If it’s overcast and there are virtually no visible shadows, then use f8

• If it’s heavy overcast with no shadows at all, then use f5.6.

• For open shade or sunsets with long shadows then use f4.

The rule also states that for the other extreme if you’re in snow or sand and it’s sunny, use f22. 

There are lots of tables available to download from the internet. I created one of my own and carried it about for a while in my note book.

My Sunny-16 reference table.

Once you have your base setting locked in, you can easily extrapolate for the aperture you want to use for creative effect. It's a simple matter of compensating shutter speed to keep the same exposure. If you come down one stop from f16 to f11, then double your shutter speed to go up one stop to keep the same exposure. If you come down to f8, go up two stops in shutter speed.

Here is a little reminder about exposure:

On the camera, there are just three things you can alter to adjust the exposure. For each item values are shown in 1-stop increments.

Film speed/ISO  

100, 200, 400, 800, 1600, 3200, 6400 and so on. 

Shutter speed 

1/30s, 1/60s, 1/125s, 1/250s, 1/500s, 1/1000s and so on. 

Aperture size 

f1.4, f2, f2.8, f4, f5.6, f8, f16, f22.

On film, the speed is determined by the chemistry and therefore is fixed and can’t be changed. On modern cameras, ISO adjustment is available from a menu, or rotary control and typically ranges from 50 to 25000 or higher. 

ISO speed is the equivalent of film speed and makes the sensor more or less responsive to light with the same advantages or disadvantages as film (increased noise or grain with higher speed value). Of course modern sensors produce far less noise now, meaning higher, useable ISO speeds make shooting in lower light even easier without the need for flash.

Shooting film is sadly, no longer a 'cheap hobby' and on my first outing with the M4, I was concerned about wasting film, processing and a lot of time if I messed up my exposures. To hedge my bets, I took along a handheld light meter and a digital camera with a screen that I could use to check the settings. I also downloaded the 'Light Meter' App onto my iPhone, which actually works a treat. 

I wanted to be free from carrying all this extra paraphernalia about by working out exposure in my head but couldn't yet trust myself to use Sunny-16 reliably. However, with these safety nets, I could practise using the rule but be sure I was right. At first, this process was slow and cumbersome but probably saved me from some duff exposures.

My fears were soon allayed. On my first roll of film through the M4, all 36 images came out just fine. I was amazed, and obviously quite relieved. I was more relaxed after the next two rolls and had confidence to shoot without a light meter soon after that. I had my iPhone with me to check exposure if needed but quickly learned to work without it. I've shot many more rolls of film since and never yet missed an exposure so badly that I couldn’t recover it. This proved to me that Sunny-16 works. 

The picture below was taken in Bristol using my Leica M4 with my first roll of Ilford HP5+ film. It was later featured in Leica Fotographie International and credited with the prestigeous 'Master Shot' award. 

Friendly Bristol Cops, taken with my 1967 Leica M4 went on to win LFI, Master Shot Award.

Sunny-16 and Zone Focussing together: 

Anyone who has attempted candid street photography particularly with a manual camera will likely be familiar with 'zone focussing'. This is manual, pre-focussing of the lens to capture people as they walk into a range (depth of field) say between 1.5 and 5m where everything is in sharp focus. The depth of field available is a factor of lens focal length and aperture (f-stop) selected. The higher the f-stop number, the smaller the aperture but the greater the depth of field. 

28mm and 35mm lenses typically provide good depth of field at useable apertures, (f5.6 or f8). For that reason they are perfect for candid street photography. Lenses are usually marked up with DOF scales, indicating the start and finish distance of the depth of field for a given aperture. The picture below shows the markings on my 28mm lens. With f5.6 selected, the depth of field available is 1.5 to 5m, or 5 to 15 feet. Whether you're metric or imperial, this is very easy to judge. Shooting from the hip, or without holding the camera up to one's eye, it's easy to frame people at this distance and get them in focus. You've just turned your rangefinder into a literal 'point-and-shoot' camera.

With focussing taken care of you have to pre-expose the image too. Auto shutter speed is quite unreliable in street photography with ever changing light conditions, or subjects in and out of shade.

Film is however pretty forgiving and even in digital, working with RAW format files, you have software exposure adjustment / recovery of around +/- 4 stops giving a lot of leeway for error. It is nice however to be close when taking the photo and definitely gives the best results with minimal required adjustments.

Consider this? What if, just by looking around as I’m walking with my camera, I could know instinctively what shutter speed to select for the aperture I’m using? 

If it’s candid street shooting I’m doing, the chances are I’m going to be shooting f5.6 or f8 and 28mm or 35mm. Well it turns out the Sunny-16 rule allows me to do just that and it works as well for digital photography as it does for film.

Over time and with more confidence, I’ve added some extra bits of information to the table depending on where the light is coming from. These days I carry the table around in my head.   

• If the subject is side-lit, you may want to increase the exposure by +1 stop.

• If the subject is back-lit, you may want to consider increasing by +2 stops.

• If shooting indoors, then best not to let your shutter speed drop much below 1/60s, or if you’ve got a steady hand, 1/30s and you’ll probably be wanting to shoot at f2.8 or wider. Indoors you'll want a fast film, ASA400 or 800. For digital I'd recommend using ISO800 or above.

• For a white subject, you may want to reduce exposure (-1 stop). For a dark or black object, use over expose by +1 stop.

Will these skills make you a better photographer? Absolutely, give it a try, it’s fun and quite addictive. Try it first using your digital camera so see how you get on.

It takes a little time to master sunny 16 but with practise youn be using it reliably.