Every photographer at some point has taken a photo thinking the image would come out in a certain way but the lens, film and camera capture something altogether different.
In a nutshell, contrast is the difference of brightness in light, in different parts of a scene being observed. On bright sunny days (which are few and far between in England) this may be extremely strong. Ofcourse in a studio these can be controlled using flash. In contrast [no pun intended!] it can get quite low, again depending on where you live on the planet!
On a very wintery day, snow, due to its albedo, can result in extreme contrast if there are shadow areas present in the same photograph.
The human eye is quite remarkable, being able to switch instantaneously, between extreme brightness of an open area to the light deprived alleyways of old London. In comparison with the human eye, film cannot process or adjust to these rapid changes.
Generally, black and white film fares much better with contrasts in brighter light and darker areas. However, in comparison to colour film, particularly in my experience, slide film stocks such as Velvia and Provia seriously struggle. Ofcourse the human eye is leagues ahead, however, technology is rapidly changing and I would not be surprised if the digital realm at some point, reaches some degree of closeness to the experience of the human eye. The question I have on this would be, do we really need it?
On average, black and white film, can handle much wider exposure latitudes. Films such as Kodak Tri-X or Ilford HP5 Plus allow for greater shifts in light and shadows. You can push-process HP5 Plus up to 6 stops but you might lose shadow detail as a result, although it generally tends to fare better in highlights. Ofcourse, if that is not enough for you, then try Ilford Delta 3200 or Kodak P3200 TMAX, these films can be shot from ISO 400 through to 25,000 making their exposure latitudes the widest available across all black and white films.
Most modern colour films such as Kodak Portra can manage one stop underexposed or two stops over-exposed relatively well, however this will depend on what you are shooting. Often, highlights render as white, if you overexpose on a sunny day, and if you under-expose the shadows may be black. In either case, you’ll have an image, but, whether it's something you are happy with, is another question!
One of the best ways to establish the ‘correct’ exposure would be to use a light meter. You can use your phone, the ‘Light Meter’ app is useful but you only get a reading for the entire scene which is not going to be ideal.
Some film cameras do have their onboard light meter, but the trouble with this is going to be similar to your phone light meter. You have two further options, using a dedicated light meter. The Sekonic L-35, which you can use specifically to meter the light and shadows, however, the best and quickest way to figure out the exposure, is to use the Sekonic Speedmaster L858D. Which allows you to take multiple exposures and calculates the best lens aperture to lock in. Using a dedicated light meter will be especially useful when shooting colour stock films.
Take for example these shots, incorrect metering resulting in overexposure of these images but when metered correctly the outcomes are much more accurate! However, with the absence of much light and overcast conditions, colour again underperforms, as you can see with these images!
Light itself is not the creator of contrast. The subject, such as buildings, are what help to create shadows. The lack of light helps to create contrast and if you take the right steps you can reduce its impacts on shooting with film.
Remember, when shooting portraits out in bright sunny conditions, take a reflector with you to fill in light into the shadowy areas of the subject. Alternatively you could use flash, but bouncing light off a reflector has its own unique qualities!
Ofcourse shooting in an extremely well lit environment, such as the deserts of Arizona will be much easier to expose for. However, shooting the sand dunes of the Sahara with its piercing light and shadows, you must come prepared and armed with a good light meter!
