Picking up from where I left off last week's overview of the most abundant films currently in production is this sprawling ramble about metering techniques for film. Analog film and digital sensors capture various aspects of the color and light spectrum in very different ways, so it's good to know the different between the two and how to exploit their respective strengths.
Modern digital sensors can capture and retain an ungodly amount of useable information in the shadow areas of a scene and, generally speaking, color negative and true black and white film can do all sorts of wonderful things with highlights that are well beyond the reach of digital sensors. Keeping this in mind, I have two general approaches to metering any given scene, depending on which hammer (I mean camera) that is in my hands as well as the overall look and feel that I am trying to achieve. Film? I meter in the shadow areas to make sure all details in the darker realm of the light spectrum are captured before pressing the shutter. Exposing for the shadows usually pushes the highlights to near "unusable" realms, but color negative film has much more gradual transitions between highlights to blowouts that you can kind of let the highlights do what they want.
Once a shadow area of film is exposed, you're pretty much done as far as depicting detail in the shadow areas of the final image. You won't find yourself unveiling 2-3 stops of usable details by yanking on the shadows slider in LightroopertureOne, so it's good to try to capture as much detail in those areas as possible when shooting film.
The same approach to the opposite side of the light spectrum goes for digital sensors. When shooting digital I do my best to keep the highlights of a scene in check and pull the details from the shadows in post. This exploits the full advantages of the truly impressive digital sensors and digital editing tools available in the modern age. It's much easier to pull together a balanced final product by brightening the details lurking in the shadows of a digitally captured image than it is to deal with blown digital highlights in the scene. Once a highlight is gone on a digital sensor, it's gone forever.
Luckily, this isn't the case for film! The nature of color negative and true black and white films provide much more interesting transitions between the bright - highlight - completely blown areas of exposure. A blown highlight won't look like a blob of unusable white data, like it does on digitally captured images.
Johnny Patience recently released the modern guide to exposing for color neg and true black and white, so read his post, re-read it, bookmark it, and then read it again for good measure. Keep in mind that Johnny uses an incident meter, but the same principles generally apply when using a reflective meter (like the one built into your digital camera).
Besides Johnny's great guide to metering for film, I'd like to add a few of my own tips to the bag, mainly, the habit of memorizing typical Exposure Values, using composition to exploit the characteristics of film stocks and metering for slide film.
The meters found in many old cameras utilize Exposure Values which are the combinations of shutter speeds and aperture combos that can be used for a particular scene. For instance, the shady side of a city street might have an EV of 11 or 12 for 400 speed film. An EV of 11 or 12 for 400 speed film translates to about f/5.6 for about 1/125 of a second. This means that whenever I encounter the shady side of a street I set my camera at about 1/125 f/5.6 and tweak the settings depending on how dark the shade is or the end result I'm looking for. After a few weeks of really paying attention to and keeping track of the ball-park settings of various scenes, your exposure settings will be 90% there by the time you bring your camera to your eye.
Another trick along the same lines is to keep the the Sunny 16 rule in mind when overviewing a scene. Match your shutter speed to your film speed (1/500 for 400 speed film, for instance) and set the aperture to 16 for full sun, 11 for clouds, 5.6-8 for shade and f2ish area for indoors. I basically stick to these and keep EVs in mind when working with film and I'm generally in the clear. If possible, I try to err on the side of overexposure as well, because a bit of overexposure can never hurt when shooting color negative/true black and white.
All of these "close enough for state work" tactics generally go out the window for slide film. The exposures for transparency slide film need to be much more exact and I usually only shoot slide in modern cameras with built in matrix, center-weighted or spot meters. Many commercial photographers and photojournalists shot transparency slide film professionally for many decades, and many of the 20th Centuries greatest color photos were taken on slide film, so there is a lot to be accomplished with this style of image capture. I just tend to not use it as much since it is quite expensive to get processed in my area.
Think of color negative/true black and white to be shooting in RAW digital format, and slide film to be a high res JPEG. The raw file will give you a lot of under/over exposure flexibility but the JPEG will have to pretty much be a finished product when the shutter is pressed. Like a JPEG file, slide exposures have to be fairly on point.