Sunny 16 Rule for Film: Exposure Chart, Zone Focusing and Metering

The sunny 16 rule is a way to estimate daylight exposure without a light meter. In clear sun with distinct shadows, set the aperture to f/16 and the shutter speed to 1 over the film's ISO, then use the nearest speed your camera has: ISO 200 film is 1/200 in theory and 1/250 on a standard shutter dial.

The rule is based on the light falling on the scene (incident light), not the light bouncing off it. That is why a white wall or a black coat doesn't throw it off the way it fools the reflected-light meter inside a camera. Its numbers are approximate: at ISO 100, 1/100 at f/16 works out to EV 14.67, while the standard bright-sun value is EV 15, about a third of a stop apart and well inside what negative film tolerates.

You don't have to shoot at f/16. Every stop you open the aperture, double the shutter speed: at ISO 100, 1/125 at f/16 gives the same exposure as 1/250 at f/11 or 1/500 at f/8. It's the same trade covered in the exposure triangle for film, and it's how you get a faster shutter for moving subjects or a wider aperture for a softer background. Some cameras even print the rule on their exposure controls as weather symbols.

Keep the shutter at 1/ISO and let the shadows pick the aperture. Kubus Photo's shadow test is the quickest version: hard edges mean f/16, soft edges mean f/11, no shadows mean f/8 or wider. Each step down the chart below is one stop more exposure.

Sources disagree about open shade. Most charts, including the common one from James Martin's field guide, put open shade and sunset at f/4, four stops more than sunny 16, and Unblinking Eye's classic exposure list also gives open shade four stops more. The ANSI exposure tables rate open shade the same as heavy overcast (EV 12 at ISO 100), which is f/5.6. On negative film, f/4 is the safer pick, because the film handles too much exposure better than too little.

The chart assumes front lighting, with the sun behind you, from about two hours after sunrise to two hours before sunset. Turn the subject and the numbers change: the ANSI tables add one stop for side light and two stops for backlight. For a backlit face, Kubus Photo says to open up two stops, so f/8 instead of f/16 at the same shutter speed.

Low sun is weaker, too. Unblinking Eye's guide says to give 1.5 to 2 stops more than the basic sunny exposure within two hours of sunrise or sunset, and about half a stop to one stop more around 9 am or 3 pm. The same list uses its cloudy-bright exposure, two stops more, for backlit close-ups.

Snow and sand are the one case where sunny 16 closes down, to f/22, because the bright ground adds light. A camera meter goes the other way in the same scene: it reads snow as too bright and turns it gray, so ScanTips suggests adding about one to two stops of exposure when you meter snow.

• Side light: 1 stop more (f/11 instead of f/16)
• Backlit subject or face: 2 stops more (f/8)
• Within 2 hours of sunrise or sunset: 1.5 to 2 stops more
• Around 9 am or 3 pm: half a stop to 1 stop more
• Front-lit snow or sand in full sun: 1 stop less (f/22)

Ektar 100

Not every reference treats f/16 as the bright-sun setting. Kodak's exposure table for Kodak Ektar 100, reproduced on Stockholm Views, lists 1/125 at f/11 for bright or hazy sun with distinct shadows and saves f/16 for light sand or snow. That is one stop more exposure than classic sunny 16, and a sunny 16 reference page by Josef Burger at UW-Madison mentions the same shift as a variation he has seen: bright sun at f/11.

Both versions are defensible. Sunny 16 matches the standard bright-sun value, EV 15 at ISO 100, about 82,000 lux. The f/11 version adds a stop of exposure, which suits color negative film: Kubus Photo says C-41 film tolerates about two stops of overexposure but only one stop of underexposure. Photographer Kim Hildebrand gets there another way, starting Kodak Portra 400 at 1/250 instead of 1/500 at f/16.

In practice: use classic sunny 16 for slide film, and lean toward the f/11 version with color negative film. The moon has its own version, the Looney 11 rule: f/11 at 1/ISO for the moon's surface, one stop more than sunny 16.

Yes, and it works best on negative film. Sunny 16 depends on your guess about the shadows, and ScanTips notes that this can get surprisingly close with practice but is usually less accurate than metering. Negative film absorbs most of that error; slide film does not.

Which way to err depends on the film. The old advice to expose for the shadows is advice for negative film, because shadow detail that isn't recorded at exposure can't be added later. Slide film flips it: protect the highlights, bracket, or meter. With Kodak Ektachrome E100 or any other E-6 film, treat sunny 16 as a starting point, not the answer.

If you rate a film at a different speed, the rule follows the number you set: ISO 400 film rated at 200 means sunny 16 at 1/250. Film ISO explained covers box speed, pushing and pulling.

Trip 35

Zone focusing, also called scale focusing, means presetting the focus distance and aperture so you know what will be sharp without looking through the viewfinder. You guess the distance to your subject, dial it on the lens, and shoot the moment something happens inside that zone. The old adage "f/8 and be there" sums it up.

It pairs naturally with sunny 16: bright light lets you shoot at f/8 to f/16, and small apertures give deep zones. Kubus Photo's grab-shot recipe is f/8 or f/11 for deep focus plus a sunny 16 shutter speed.

Hyperfocal focusing is the special case where the far edge of the zone reaches infinity. Focus at the hyperfocal distance and everything from half that distance to infinity is sharp: DOFMaster's example is a 28mm lens at f/16 on 35mm, with a hyperfocal distance of about 5.5 feet and sharpness from 2.75 feet to infinity.

Some cameras only focus this way. The Olympus Trip 35 has a four-position zone focus, the Olympus XA2 has three settings (person, group, mountain), and the current Pentax 17 half-frame focuses in six manual zones from 0.82 feet to infinity, covered in half-frame cameras. Toy and viewfinder cameras such as the Diana Mini and Rollei 35 work the same way.

Focal length changes everything. On the lenses Casual Photophile compared, a 50mm at f/8 was sharp from about 15 feet to infinity, while an 18mm at f/8 reached down to about 3 feet. That is why street photographers who zone focus usually pick 28mm or 35mm lenses on full frame at f/8 to f/16, and why telephotos are a poor fit: a 200mm at f/16 has a hyperfocal distance of about 275 feet. If you are choosing a lens for this style, go wide, roughly 21mm to 35mm on 35mm film.

Hyperfocal and depth-of-field charts depend on an assumed circle of confusion, the sharpness threshold, and DOFMaster suggests 0.030 mm for 35mm film. Fstoppers notes that Jeff Ascough's presets reflect 35mm film and an 18-megapixel camera: on a 60-megapixel sensor the soft edges of the zone show more, and you may need to stop down further. Either way, keep your subject near the middle of the zone, where sharpness peaks.

When you do use a meter, know which kind you have. Every meter built into a camera is a reflected-light meter, calibrated to give the right exposure for an average scene. The Pentax K1000 has a through-the-lens average, match-needle meter rated EV 1.7 to 18 at ISO 100; the Canon AE-1 meters center-weighted through the lens.

An incident meter reads the light falling on the subject, so pale or dark subjects don't fool it. You hold it at the subject's position with the dome pointed at the camera, under the chin for a portrait, which isn't practical for a distant landscape. A spot meter is a reflected meter with a narrow angle, typically 1 degree, for reading shadows, midtones and highlights separately.

No meter at all? A handheld meter, a phone app or sunny 16 all work. To check a used camera's meter, compare it with a reference meter or app in bright, indoor and dim light: Kubus Photo says healthy readings agree within one stop.