Most of the time the automatic exposure setting on your Digital SLR will produce fine images. The camera’s brain along with the lens’ impressive array of sensors can usually figure out the best balance between shadow and highlight and provide a decent image. A perfect record of a moment in time. To me, photographers are the ultimate historians, but that is for another time.
Historical photography theories aside, there are times when you want to convey more than just a moment in time. Perhaps you want to add more light to a sunny country garden scene to give it a misty impression. Or maybe you want a portrait to have a dark, brooding feeling. Automatic settings will capture the moment in time, but to express yourself you need to be able to twist and bend the light like a sculptor does with clay.
As with any tool, the quality of work it produces depends entirely on the competence of the user. The tool itself is merely the apparatus your mind uses to create a physical object from the neural info stored in your brain. A Digital SLR (DSLR or any manual camera) is designed to be intuitive. The basics are simple, and the learning curve is short, if you practice. Take your camera everywhere, shoot everything on manual mode. Erase nothing. Keep track of your settings, figure out what works best.
I will show you how to use the manual mode on your camera, my bet is that you will never use automatic settings again after a little training.
Three Main Components
Shutter Speed
Aperture (fstop)
ISO (film speed)
Shutter Speed
The shutter is the mechanism on the camera that opens for a predetermined period to expose the CCD sensor to the light from the lens. The longer the shutter is open, the more light is allowed to fall onto the sensor. Shutter speeds are measured in fractions of seconds. Shutter speed is generally adjusted by the thumb wheel with the right hand.
Example: A shutter speed of 1/2sec is open 50 times longer than 1/100sec. A shutter speed of 1/100sec is open 50 times longer than 1/5000sec.
In general, slower shutter speeds means a higher chance for blurry pictures. Since the shutter is open for a longer period, any movement will show in the photos. When taking photos of moving objects, always use the fastest shutter speed possible.
Aperture (fstop)
The aperture in a camera works very much like the iris in your eye. It’s main function is to regulate the amount of light allowed into the eye, or in this case, the camera. As with the eye, the iris is also critical in focusing and depth of field. Instead of tiny muscles contracting and expanding according to lighting conditions, the aperture has several petals that overlap to make a circle in the middle where the light passes through. A ring on the lens, or a servo motor in the camera is turned by the photographer to adjust the diameter of the aperture.
Designation: A large aperture opening has small numerical designation. A small aperture opening has a large numerical designation.
Example: An aperture setting of 4.5 is larger (more light) than an aperture setting of 22 (very small opening, less light).
Depth of field: If you want to have foreground and background objects in focus in a photo, you will need to use a smaller aperture opening. A smaller opening compresses the image in the lens, and a byproduct of that is the depth of field is much greater. This means that more objects will be in focus in the photo, regardless of distance from the camera. Many sports photographers use large depths of field to show the crowd reaction AND the action on the field in one shot. Many nature photographers prefer to blur the background to isolate the animal or flower they are shooting. Having control of depth of field is critical in expressing emotion in photography.
ISO
The ISO setting is simply an expression of how sensitive you want the image sensor to be. Choosing ISO speed is the same as choosing film speed in the old days.
The larger the ISO setting, the more sensitive the sensor. You might ask why isn’t the camera always set to the most sensitive setting at all times? The answer is because that higher ISO speeds produce very ugly noise on the images. In fact, the lower you can keep your ISO setting the sharper, crisper the images will be. Low light situations will call for higher ISO’s, but always use the lowest setting possible for the situation. Don’t forget to shoot in manual mode!
Built in Exposure meter
Use the meter in the eyepiece as a guide, learn to read it and it will help fine tune your shots.
Summary
Used together with manual mode, these three components provide countless exposure combinations. As you shoot and become more comfortable with the relationships between the components, the relationship between the components and you, and your relationship between you and your own personal creativity, you will develop the most important part of being a successful photographer, a unique style.
Nice article,
very helpful