Because I write about photography, I tend to watch the way people use cameras. One of the things that I consistently see is how many people simply shoot on Automatic. That is, they set the camera to Auto and go off, and take pictures. They do not make adjustments and I don't even see them use their zoom lenses to reframe a shot. This behavior is the result of the digital cameras generally working correctly, but it has its downside.
For instance, I have a friend who is new to photography. She bought a digital Single Lens Reflex camera that came with an instruction manual written in gibberish. Crystal was interested in photographing the "corrida" (the bullfights) but had no idea about how to go about doing it. So she set the camera Exposure Mode dial to "Sports" thinking that bull fighting was a sport, except that the Auto to Scene to Sport setting made it harder for her to get good photos. When she told me her problem we had a long talk and this column is for Crystal and everyone else who is still bewildered by their digital camera. Think of it as a short course in digital cameras for new camera owners and a review for the rest of you.
The sensor is a very tiny integrated circuit composed of millions of little photocells. When light falls on a photocell it generates a current of electricity. A 12 MP (megapixel) sensor, for example, has more than 4000 columns of cells in 3000 vertical rows in a space of less than a square inch.
The physical size of sensors varies--a "Point and Shoot" camera has a sensor that is much smaller than the one in a dSLR--nevertheless, under the right conditions and when properly used, any camera, regardless of sensor size, can produce great photos. Any sensor of 6 MP or larger, can produce excellent images for magazine reproduction or jury submission.
A zoom lens has a variable focal length. It may be attached to the body or removable and interchangeable. The zoom lenses that come with most cameras are typically moderate wide-angle to moderate telephoto in range. The exceptions to this are the "Superzoom" cameras that have lenses with extreme telephoto range.
While the wide-angle end of a zoom is good for landscapes, interiors and group shots, for crafts photography, the moderate telephoto setting is more useful, particularly for objects like pottery, wood, etc. Most zooms have some close-up capabilities. For jewelry and such, look for a lens with close-up or macro capability at its telephoto end.
This is the measure by the International Standards Organization of a sensor's sensitivity to light. Most sensors have a "native" ISO of 100. This is their baseline sensitivity to light. At ISO 200, the sensor is twice as sensitive to light as it is at ISO 100, and that means you need less light for pictures.
When you increase the ISO setting, the photocell signals are amplified, similar to turning up the volume on a stereo. For most digital cameras, ISO settings between 100 and 400 are the best to use for craftwork. At higher settings, particularly with small sensor cameras, you can experience "noise," artifacts or spots in the image.
Exposure is the term for the light is required to produce a richly colored and toned photograph. For any sensor, at any ISO, there is a fixed amount of light needed for a correctly exposed photo. The amount of light falling on the sensor is measured and the camera processor turns this into a selection of aperture and shutter speed settings.
The aperture is a device placed between the glass elements of the lens. It controls how much light gets through the lens to the sensor. The aperture affects the depth of field or overall sharpness of an image. At "wide open" settings like f3.5, the depth of field is very narrow, for crafts photography, an aperture of f/11 is good or f/16, better. (see photos)
With the lens aperture at f/4, depth of sharpness is very narrow, and the bellows on this old wooden camera is out of focus.
With the aperture at f/11, the sharpness is deeper, but note that the enitre bellows is still not in focus. An aperture of f/22 would help.
The shutter controls how long the light falls on the sensor. Shutter speeds are in fractions of a second and most photos are taken at 1/60th second or higher. Generally the shutter speed is less important than the aperture.
Exposure Mode Dial
This dial allows the photographer to control how the exposure settings are determined. It is the large dial on the top of the body, marked with AUTO, P, A, S, M, movie, and scenes.
AUTO-At this setting the camera makes all the choices according to pre-programmed settings. The photographer has no control.
P-Programmed, the camera selects both the aperture and the shutter speed, although the photographer can change them.
A-Aperture preferred. The photographer selects the aperture and the camera finds the shutter speed for correct exposure. This is a useful setting for crafts photography, because you can select an aperture of f/11 or f/16 to ensure sharp images.
S-Shutter preferred. Here the photographer chooses the shutter speed and the camera selects the correct aperture.
M-The photographer sets both the aperture and shutter speed, using an icon in the viewfinder or on the monitor display.
"Scene" settings such as Sports, Baby1, Baby2, or Night Sky are factory-installed presets that really do not make photography easier and certainly should not be used for crafts photography.
Exposure Compensation Control
Despite all the technology built into digital cameras, they remain dumb and unaware of the world. The camera uses sensor information to determine exposure but has no way of "knowing" what it is seeing. Metering systems make everything an average gray. Cameras have exposure compensation controls (either a button on the body marked (+/-) or a menu page) that allow you to fix this problem.
With the camera set to Auto-Exposure and Auto White Balance, the bottle on the white background was underexposed and had a color cast.
Using the Exposure compensation dial, I added + 1-1/3 stop and got this image with better tones, but a little pink cast.
Next, I set the White Balance to daylight--the bottle was on a background lit by window light and got this image with a cleaner background.
WB corrects for color variation in the light. It ensures correct colors in the image whether you shoot under sunlight, tungsten lamps, or fluorescents. However, set to Auto White Balance, the control can make incorrect choices. It is better to use the WB set to the actual lighting conditions, daylight, flash, floodlight, or whatever. (see photos)
This is the term for the new digital, mirrorless cameras. Unlike the dSLR, they have no pentaprism viewfinder systems. Viewing and framing is done with an EVF (electronic viewfinder--a tiny TV) or on the LCD monitor making the mirrorless cameras small and light-weight. As the popularity of these cameras grows, more camera companies are producing them. They are especially useful for crafts photography because as you change camera settings, you see the effect directly on the EVF or monitor screen. Change the White balance and you will see the colors of the screen image alter. This makes it easier to get the correct colors in your craft images.
Knowing and remembering these basics will help you take better crafts photos, especially as soon as you turn off the Auto settings.