Using an incident light meter is definitely the best way to determine exposure - especially with a film camera with no built in meter. Even free smartphone meters do a good-enough job. But with experience, exposures can be guessed quite accurately using rules of thumb and converted to an equivalent setting for creative purposes. In this post, I'll explain those things along with some common settings for various purposes.
Full settings assuming 400 speed film is in the camera:
- Outdoors, general shooting. 1/250 f11 in full sun. 1/125 with cloud. I'm over exposing and keeping a small aperture to help when zone focusing.
- Outdoors, lights at night. 1s f8. This works for scenes like fountains or downtown buildings with the lights on. To get more depth of field, reciprocity starts to kick in (explained in the section below) so that the calculated 4s, f22 must be converted to about 10s f22.
- Indoors, bulb lights. 1/60 f2. Slight under exposure to prevent motion blur. 1/30 is preferable if you have steady hands and a steady subject. f2.8 is pushing it.
Partial settings for specific scenarios:
- Indoors with flash. Sync speed and f8. The fastest possible shutter speed compatible with flash means your lighting is completely in control. Exposure is a function of flash power and a light meter or digital camera (the modern Polaroid) must be used to determine the settings. f8 is in the sweet spot for image quality.
- Star trails - avoid them by keeping exposure time to under 10s. Star trails that look like they were taken on purpose start at 15 minute exposures. 60 minutes and beyond creates impressive trails. f5.6 is a good starting point, but not that critical.
- Light trails. Shutter speeds of 10s to multiple minutes.
- Water movement. 1/500 or faster to freeze it. 1/125 is mushy. 1/30 looks blurry. 1/4 is smooth. Exposures in the minutes make water look like fog.
- Aircraft with propellers. 1/25 to 1/125 to get a desirable blur. Freezing the propellers makes the plane look like a stationary model. For jets, any speed is fine.
- Moving vehicles. 1/125 and below for panning shots.
- Black and white film is very forgiving when it comes to exposure - especially if you are scanning the film and processing on a computer. Definitely better to over expose than under expose.
- Know what the full stop numbers are for aperture and shutter speed. The reciprocal rule (explained below) helps convert a rule of thumb into a purposefully creative settings combination. Apertures values: 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32... Shutter speeds: 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15...
- Keep things in full stops to keep it simple. Half stops are over-kill. You only need to consider half stops when you have a quirky lens like an f1.8 or f3.5. 1/3rd stops are for delicate studio lighting setups.
- For normal focal lengths, I'm keeping the shutter speed at or above 1/60 to prevent blur from camera movement and it freezes most things bar fast cars and small children.
- Purposefully blowing out the highlights or making silhouettes can be achieved by altering shutter speed and aperture, but I find it can easily be done in post production. It is easier to remove detail from a well exposed image than to add it back in to a over or under exposed one.
- Manual settings can at times be faster to use than automatic ones.
The sunny 16 rule
- This is great for street and travel shooting. In full sun, use f16, set the shutter speed to 1/ISO and you're done. I use HP5 (400 ISO) most of the time so I could use 1/500, but often round down to 1/250 because over exposure is preferable to under exposure.
- A little cloud and I'm down to 1/125. Heavy clouds or shadowy areas get 1/60. I don't like to go slower than 1/60, so I open the aperture as dusk sets in.
Equivalent settings / reciprocals
- Any part of the exposure triangle can be changed, but if the total exposure is to stay the same, the other parts of the triangle must be modified to compensate. For example, if we are using sunny 16 in full sun with 400 speed film, we would use 1/250, f16. If we want a shallower depth of field, we can open the aperture and compensate by making the shutter go faster - 1/500 f11 and 1/1000 f8. When the maximum shutter speed is reached, an ND filter can be used to block more light so an even wider aperture can be used.
- With film, the equivalency rules break down with longer shutter speeds as the chemicals do not react to light linearly with time. This is known as reciprocity failure. It is fine from fast speeds down to about one second, but beyond that extra time needs to be added to compensate.
- For example, with Ilford's HP5 film, the technical information sheet (find it here) uses a graph to convert a calculated shutter speed into a practical one. For example, 5s becomes 10s, 10s becomes 30s, 20s becomes 75s, 30s becomes 3 minutes.
F8 and be there
- This guidance is for getting a shot with the least amount of fuss.
- The saying comes from Arthur Fellig, who was limited to slower films than we are now. When using 400 speed film, I use f11 for 16 so I don't max-out my shutter speeds. A positive side effect is that the sunny 16 rule can then be used without the conversion to f8 (two stops).
- f8 gives a large enough depth of field for zone focusing, and more-so with f11. Set the focus so the infinity mark is over the f8 indicator on the right and the zone of acceptable focus is so large you wont need to touch the focus again.
- Be there. Put yourself in-front of something worth taking a picture of.