The time is rapidly approaching for some great outdoor photography when some of the best pictures are taken during the time of sunrise and sunset. I'll try to point out some of the idiosyncrasies of shooting at those times, and the basic equipment, problems, and techniques used.
Notes from Lyle
By Lyle Trusty
The Problem: The exposure latitude of slow speed, high resolution film is approximately plus or minus one and one half f-stops. Outside that range, resolution and color fidelity deteriorate rapidly. Digital camera sensors have similar limitations that show up as loss of detail in shadows and highlights. Left to the normal method of determining exposure, most camera metering systems will average all the light values it sees, overexpose the sky and underexpose the landscape. If you try to compensate over-exposure of the sky by reducing the over-all exposure, the landscape becomes just a silhouette. It's true the sky will darken, and the colors will pop out, but it leaves a silhouetted landscape. That might be a great snapshot, but is generally not considered to be a good entry in a competition.
Equipment: It's your choice to use film or digital cameras, because you can use either one to accomplish the task. In each case use a tripod and remote shutter release. The best light occurs at twilight, i.e., after sundown, and before sunrise, when slow shutter speeds, small apertures (f-11 - f16) and wide angle lenses (24 mm) are the means by which you get the large depth of field required for scenic shots. Ektachrome 100VS or Fujichrome 50 or 100 is a good choice because they are highly saturated emulsions. You may favor others, I’m only suggesting you use slow speed film. The reason for that is so you have the potential for huge enlargements without showing grain. More recent Digital Cameras are showing good results at higher ISO ratings but generally speaking they will display “grain” at higher ISO's too.
Preparation: Good twilight pictures take careful preparation, and you usually have to decide beforehand whether to have breakfast before or after the shoot. (I suggest that if you must eat something, have a banana to tide you over.) If you don't have a specific location in mind, a scouting trip the day before the shoot is always a good idea. You need to find an accessible place facing the sunrise that will give you foreground, middle-ground, and background interest. Pre-op planning should include looking up local sunrise time so you can be in place 30 to 45 minutes prior to sunrise. In conjunction with that, notice that in the spring the sun rises in the southeast, gradually moving to the east by June 22nd. The real light show begins before the sun rises above the horizon, or just after sundown. The sun's rays shining up under the clouds through a hundred miles of microscopic particles in the low altitude layer of atmosphere around the earth have had the blue wavelength rays filtered out, however, the longer wavelength red rays make the journey, and turn the clouds yellow, gold, and red.. The difference in light colors depends upon the circulation of atmospheric contaminants. The wind at 22,000 feet at 2:00AM will generally descend to the earth's surface twelve hours later, where it picks up another load of microscopic contaminants, carries them aloft, and starts the cycle all over again.
Technique: The technique for overcoming the latitude limitations of both film and digital photography is to use a graduated neutral density filter to mask the sky. The dark half of the filter, positioned over the sky portion of the picture will hold back the sky exposure and bring the total exposure into a more proper balance.
When you get it right, the foreground will be correctly exposed, the sky will be extravagantly lit up and the picture will look like what you saw in the viewfinder. Three or more densities and graduation transitions are available from Sing Ray or Mountain Light Photography in Bishop, and the filter adapters are available at small expense from King Photo. Most photographers will start with a three stop density, and a sharp transition filter. Position the filter in its holder, while looking through the viewfinder, so that the transition falls on the horizon. Bracket at least three exposures. If you have a Digital Camera with a Histogram, adjust the exposure to give you the most pixels in the 60 to 70 percent range. Being able to preview the picture on a digital camera display is a definite advantage in this case. Using the cameras spot meter mode will allow you to determine the sky and foreground exposure differences, and is a good place to begin. Don't point the spot at the sun, you could ruin the meter, but do get an average sky reading versus an average ground reading, to determine how many f-stops difference there is.
You will find that there is very little time at optimum light, and you may have great changes in a matter of minutes. Don't forget to look behind you when taking these kinds of pictures. You may find the sun lighting up mountains behind you in a red glow while you are staring at a flat sky in the other direction. Knowing your equipment and being well organized will maximize your chances of getting good exposures, whereas trying to sort things out at the time of peak intensity is generally futile.
Digital Techniques: People adept at Adobe Photoshop can take two or three pictures in RAW mode at different exposures, combine them using “layers”, and produce a composite picture that represents the best exposure for both the sky and the landscape. There are only a few members that have the ability to do that, and we may all gravitate to that method in the future, however, the methods explained in this paper will be a good foundation on which to add another dimension to your photographic capabilities. One you can use in several other applications besides sunset/sunrise scenes.