The first few posts on this blog were what I would call introductory and general postings about the site and its photographs. In this and the next several postings I hope to address specifics about the equipment, techniques, and processing that are fundamental to nature photography. Since there are many experienced photographers, professionals and advanced amateurs, viewing this site, I hope the posts will generate questions, comments, and discussion - so please, join in.
Selection of a camera is about as fundamental as it gets when you want to take pictures of our natural world. While the brand of camera is not so important, the features available and the quality of the camera are crucial for good image capture. In other words, a good camera can be used poorly and result in mediocre photos but a bad camera, generally, cannot produce good photos. Having said that, there are many good point-and-shoot cameras and even mobile phones that can take very good photos, but at some point all serious nature photographers will want to take the plunge to a digital single lens reflex (dSLR) camera. Why do I think this is true?
The dSLR gives the photographer tremendous flexibility and choices when photographing in a variety of conditions and terrain. So what are the characteristics of a dSLR camera? The major difference between a dSLR and a point-and-shoot or super-zoom camera is the availability of multiple, interchangeable lenses (and the internal mechanics that allow this.) Interchangeable lenses give the photographer the choice to determine perspective, range of focus (depth of field, DoF), and composition of a photo. Changing lenses changes the "feel" of a photo and not just the sense of closeness to the subject. Modern dSLR cameras can use standard lenses, wide-angle lenses, telephoto lenses, and a variety of specialty lenses used in creative photography. Manufacturers of the lenses offer a variety of quality and, therefore, price of the lenses to allow lower cost investments initially and higher cost investments for higher quality as skills progress. Lenses are the most important and most expensive part of a nature photographers equipment and I will use a later posting to discuss lens selection in greater detail.
Other features in a dSLR camera that offer flexibility and creative control include the ability to move from automatic control of the camera settings to manual control of virtually all of the settings. You might think that automatic control is a good thing, and sometimes it is, but being able to adjust the settings manually can dramatically alter the quality of your photos. The three components of proper exposure of a photo can each be controlled manually on a dSLR camera. The aperture size determines how much light passes through the lens to the image sensor. Aperture, as we will discuss in more detail in the next posting, also is a key component of the range of focus or depth of field (DoF) in an image. Shutter speed determines how long the sensor is exposed to light coming through the lens. Shutter speed is another key component of exposure but also determines the effects of movement (either the subject or the camera) on the image. The third determinant of exposure that can be controlled on a dSLR camera is the ISO or the sensitivity of the sensor to light. These three components of exposure (aperture, shutter speed, and ISO) will be discussed in depth next time.
Another setting that can be adjusted automatically or manually on a dSLR camera is the focus. The ability to focus manually is crucial to the nature photographer who often has to shoot through a cluttered scene. Most auto focus systems adjust the lens to the point of greatest contrast of the nearest object in the area of focus. Sometimes this is the subject of the photo and sometimes it is a tree branch in front of the subject. With a dSLR camera you can focus manually or you can choose the point in the viewfinder that the camera will choose as the primary subject. Most dSLRs allow multiple ways to select the focus automatically as a single point, from multiple points, and even from points tracking a moving subject. Since focus is one of the five ways to ruin a photo, this flexibility is needed in nature photography.
Auto-focus speed is another key factor in selecting a dSLR camera. Shutter lag was a technical problem introduced by digital photography. There is nothing worse than pressing the shutter button and having the camera take the photo a third of a second after the bird took off! Shutter lag is still common in point-and-shoot and super-zoom cameras (although it is improving) while quality dSLRs capture the image when you press the shutter release.
Most dSLRs offer the ability to shoot in high speed bursts of images. This is very helpful when shooting birds in flight or a rapidly moving animal. The burst rates have increased from about 3-4 frames per second to well over 12 fps. This feature is useful in sports photography as well as nature photography.
While image sensors are improving rapidly in all cameras, dSLRs tend to have the largest sensors and the highest resolution in each manufacturer's product line. Sensor size and resolution are key components to high quality images and the ability to print these images at a large size. While the pixel count is highly touted in camera ads, it is really the sensor size and pixel size that determine resolution of the image. Larges sensors that approximate the size of 35mm film are referred to as full-frame sensors while smaller sensors are called crop sensors. There are advantages and disadvantages of each but dSLR cameras seem to be moving towards larger, full-frame sensors, even though the cost is typically higher.
The last advantage of a dSLR camera over others tends to be the quality of the construction. The dSLRs tend to be larger, heavier, and have a ruggedness with more metal rather than plastic construction and better seals to prevent dust and water from entering the camera and damaging the sensor or internal mechanics of the camera. These are important to the nature photographer but also create problems of greater bulk and weight when photographing in remote locations.
So like everything in life there are trade-offs when selecting your "perfect" camera. Features are critical, quality is essential, but there are many good quality cameras available that, when coupled with a quality lens, will produce amazing photographs.