close-up photography and macro photography
Different authors and manufacturers use the terms close-up photography and macro photography in different ways, often meaning different things, and it is important that they are clarified right at the start. Close-up photography is usually applied to any situation where the subject is closer than “normal”—in
other words, a rather vague and meaningless term. To a wildlife photographer, being within 15 feet of a hungry crocodile is close up! In this book, close-up photography describes when the subject is reproduced at around one-tenth of life size or greater on the image sensor in the camera.
The term macro photography has a more tightly defined definition, generally being used for photography where the subject is reproduced at a magnification of life size or greater.
Magnifications up to around 4× or 5× are relatively easy with digital single-lens reflex cameras (SLRs) equipped with appropriate lenses and accessories.
Micro is another related term worth mentioning. The term is applied to photographs taken with the aid of a microscope, strictly known as photomicroscopy.
Micro photography, on the other hand, is the photography of large subjects and then making them into very small images such as micro dots, or the photography of, for example, large circuit boards and then making them small integrated circuits.
In the world of close-up and macro photography, we use the concept of reproduction ratios to give an indication of magnification. This is particularly important if you are trying to give a real indication of the subject’s size for identification purposes.
If a 25-mm-long subject is focused so that it fits exactly onto a 25-mm imaging sensor, the reproduction ratio is 1 : 1, or 1×; that is, it is reproduced on the sensor at life size (all three of these terms are used in various books and other sources). If a 50-mm subject is focused so that it fits onto the same 25-mm.
Digital camera technology has improved vastly over the last few years, and is still rapidly evolving, with new camera designs and features being introduced almost on a daily basis, and relative costs falling too. The image quality nowadays from a good camera can be nothing short of outstanding if used properly, and with all its advantages over film, in particular, instantly viewable images, there has never been a better time for close-up photography.
There are three main types of camera in general use: compact, prosumer or “bridge,” and single-lens reflex. They can all be used very successfully for close-up and macro photography, though some models will have specific
limitations. Which type of camera and model you buy will depend largely on what you are going to do with the images, your budget, the subject matter, and your personal preference.
Compact cameras are generally small, lightweight cameras that can be carried in a pocket, but are still capable of outstanding results. Some models use an optical viewfinder separate from the lens that takes the picture. This can lead to parallax error, where the viewfinder sees a slightly different view of the subject than the lens actually taking the picture, leading to framing problems, particularly when used for close-ups . This is a major problem with film cameras, often leading to part of a subject being cut off. With digital cameras, however, this problem is largely solved because the image can be reviewed on the LCD display on the back of the camera. Many compact cameras nowadays do not have optical viewfinders at all. Instead, the camera is held away from the face and the image composed using the live image on the screen on the back of the camera. Images can be very difficult to see in bright sunshine, however, so this method doesn’t lend itself to critically evaluating the whole of the image before the shot is taken, and therefore is generally not recommended for serious work.
Most compact cameras have zoom lenses—that is, a lens with a variable focal length. Typical ranges are 38–114 mm (3× zoom) or 36–180 mm (5× zoom), and most will focus very close to a subject, often down to 4 cm (1.7 in.) in macro mode. When used very close to a subject the amount of light falling on the subject may be blocked by the camera itself, and the built-in flash may miss the subject altogether by passing over the top of the lens.
The minimum aperture of most compact cameras is relatively large in comparison to their SLR cousins (typically f/5.6 or f/8), but due to the small size of the sensor, this may not be too much of a problem with regard to depth of field. Indeed, it may be difficult to obtain a sufficiently shallow depth of field if required. (See more on depth of field in Chapter 3.)
The majority of compact cameras have automatic focusing, which may not focus on the most important part of the subject in some cases (e.g., a spider’s web). If you intend to use this type of camera primarily for close-up and macro work, choose a model with a manual focusing facility.
Several accessories are available for compact cameras to increase their macro capabilities, including ring flash units.
(0.5 in.) in some models. Most models have a range of accessories, including lenses that attach to the front of the main camera lens to increase its close- up capabilities (or extend the wide-angle and telephoto capabilities). One in particular, used by several insect photographers, is the Raynox series of close-up lenses.
Both compact and bridge cameras have imaging sensors smaller than DSLRs. For example, the Nikon Coolpix P80 bridge camera has a 2 3-in. sensor containing 10 Mp. The issue of depth of field and focal length will be discussed in more detail in Chapter 3, but in general, smaller sensors have a larger depth of field for a given image magnification. Therefore, the depth of field with this particular model will be much greater than with a DSLR. An aperture of f/5.6 may give the same depth of field on this size of sensor as a DSLR with an APS-C-sized sensor using an aperture of f/11. The main drawback is that you will need to be much closer to the subject than the DSLR fitted with a macro lens.
Many models nowadays also have image stabilization features built into them, helping to improve image quality for handheld shots.
Having a sealed, noninterchangeable lens eliminates one of the problems of interchangeable-lens DSLRs—that of dust on the sensor.
The interchangeable-lens DSLR is by far the most versatile camera type for close-up and macro work, enabling the use of a wide range of focal-length lenses, extension tubes, bellows, and teleconverters. The camera body can also be attached to telescopes and microscopes for other photographic applications.
DSLRs use a focal plane shutter, similar to SLR film cameras, and there is virtually no delay, or lag, in their operation. Many models can shoot several frames per second, which is essential for sport or wildlife photography.
Essential features to look for in a DSLR to be used for close-up and macro photography include a depth-of-field preview button, mirror lock-up, PC socket (for connecting an external flash), and the ability to manually focus the lens. Many of the cheaper models lack some of these features.
DSLRs are available with a range of different sensor sizes, usually either the APS-C size (and variants) and the full-frame (35 mm) size. The Olympus Four- Thirds system is another standard size, similar to the APS size (see the Image Sensors section later in this chapter)
New features are appearing all the time, with automatic sensor cleaning and live view options being found on many current models. Several models have recently come on the market with a high-definition video recording capability.
Camera Features and Settings
There are many features and settings that you should be aware of when making a camera choice.
Digital cameras offer an extensive range of quality settings, using terms such as fine, best, good, and basic. (Unfortunately, the terms are not consistent from one manufacturer to another.) For most macro and close-up work, use the maximum quality setting; you can always make lower-resolution versions,of your images for other purposes (such as Web display and digital projection) afterward if needed. Having the highest quality will also mean that you are able to crop the image if necessary.