Unfortunately, the lighting range of most forest scenes lit by direct sunlight is usually more than four stops. Add the white spray of a waterfall and wet, black volcanic rocks to your scene and there can be a seven to ten stop difference between your highlights and your shadows. Photographers experienced in darkroom techniques can compress or expand the range of their black and-white film's contrast by reducing or adding time in the film developer. Not so easy when you're shooting color negative film. That's why I recommend that you save your film for the cloudy days, the rainy days, and the locations where your whole scene is in shadow.
Nature photographers looking for forest scenes hope for a thin overcast or a cloudy day.
An open, luminous light dispersed and diffused by fog is ideal. Waterfalls flowing northward, in the shadow of the mountains, especially during the winter months are most easy to photograph. Skylight and warming filters will remove the blue cast reflecting from the water and the wet rocks. A polarizing filter will cut the glare of the sky on the foliage of deciduous trees around the falls. For the past seven years Robert Hitchman has published the Photograph America Newsletter .