Eloquent Images by Gary Hart
Insight, information, and inspiration for the inquisitive nature photographer
It isn’t easy, but it is simple
Spring Meadow, Rocky Mountain National Park, Colorado
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Easy: Achieved without great effort
Simple: Plain, basic, or uncomplicated in form, nature, or design
Photography may not be easy, but it is simple. Huh? What I mean is that the difficult part of photography is the creative stuff that by definition defies quantification, rules, logic, and reason—to be truly creative, something can’t have been done before. But before you can graduate to creative photography, you need to master the logical stuff–fortunately, that is simple.
Grasping photography’s simplicity starts with understanding that you’re only dealing with three variables: light, depth, and motion. To control them with your camera, you have shutter speed, aperture, and ISO. That’s it. Your job is to decide the combination of shutter speed, aperture, and ISO that returns the desired combination of light, motion, and depth. You could leave it to your camera to decide, but all automatic metering understands is light—your camera has no idea of the motion or depth effects that are so essential to creative results.
For landscape photographers still trying to get handle on their exposure settings, I think it’s best to start simple. I’ll start with the assumption that you’re working in a static world (generally true, but far from absolute—I’ll bring motion in later). Static requires a tripod—without one, all bets are off, as you’re adding unnecessary motion by virtue of your own unsteady hands (sorry). Don’t talk to me about high ISO performance (a compromise—why not go with your best ISO whenever possible?), a wide open aperture (another compromise that could reduce sharpness), or image stabilization (good, but never better than a rock-solid tripod).
Manual exposure made simple
ISO: So, if you’re on a tripod and your scene is static (no subject motion), you can go with your camera’s best ISO (usually 100, but 200 on some Nikon cameras). That’s one of our three variables out of the way and we haven’t even thought about exposure.
Aperture (f-stop): Landscape photographers shouldn’t use their f-stop to control light. Rather, the f-stop you choose is first determined by the depth of field you need. And if everything in your frame is at infinity and DOF isn’t a factor, go with your lens’s sharpest f-stop—because most lenses tend to be less sharp at their extreme f-stops, you should default to the middle f-stop range, usually f8 to f11, unless the scene dictates otherwise. (And in addition to optical problems, going much smaller than f11 risks diffraction that reduces your lens’s ability to resolve fine detail.) Read my “Depth of field” tips page for more info. We now have two of three variables out of the way, and we still haven’t even thought about exposure.
Shutter speed: With ISO and f-stop out of the way, only camera variable remaining to manage the light in your scene is shutter speed. At this point I simply aim my spot meter at whatever I decide is most important and dial in the amount of light I want it to have.
ISO part deux: If there’s motion in the frame (wind-blown leaves or flowers, flowing water, etc.), I’ll compromise my ISO to achieve the shutter speed that will freeze the motion or return the desired effect.
Admittedly, what I’ve outline here is a simplification—there are definitely situations where you’d want to deviate from this approach. But for someone just getting up to speed with manual exposure, this will work at least 90 percent of the time, and the more you do it, the more comfortable you’ll become making exceptions. For more on exposure and metering, read my “Exposure basics” and “Manual exposure” tips pages.
For example
These blanketflowers (gaillardia aristata) in Rocky Mountain National Park were the star of the scene. To fill my frame with the flowers and shrink the mountains to the distant background (that’s the creative part), I went to 17mm, as wide as my lens permitted and dropped down to about six inches from the closest flower.
My tripod eliminated camera shake, so the only motion in the frame I needed to worry about was the flowers’ motion in a light breeze. The relatively narrow dynamic range (difference between the lightest and darkest parts of the scene) made exposure pretty straightforward, but the potential for motion in the flowers and the extreme depth of field I needed made the way I achieved my exposure extremely important: too long a shutter speed and the flowers would blur in the breeze; not enough depth of field and the flowers wouldn’t be sharp enough.
With the closest flower only six inches from my lens, I knew it would be impossible to keep all the flowers and the mountains sharp. But I wanted the flowers sharp and felt I could live with a little softness in the distant mountains, so I stopped down to f20 and focused a little behind the closest flower, about one foot into the frame. F20 at ISO at my native (ideal) ISO 100 gave me a 1/10 second shutter speed. While I might have been able to time my exposure for a lull in the breeze that would freeze the flower at 1/10 second, I bumped my ISO to 200 and shutter speed to 1/20, just to be safe.
Click.
Eloquent Images by Gary Hart 
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