Macro photography is close-up photography. The classical definition is "photography in which the image on film or electronic sensor is at least as large as the subject". This definition means that on 35mm film the camera has to have the ability to focus on an area at least as small as 24.36 mm, as this is the size of the image on the film. This is a magnification of 1:1.
In insect macro photography, close-up filters and macro lens are some of the most essential items to compliment any camera. In general, a digital camera's built-in macro capability is unable to achieve a magnification good enough to capture fine details of most insects. The macro mode of most cameras requires you to be as close as 2-3 cm away from the subject. This is far too close, and most insects will naturally flee when something gets this near. Zooming doesn't help either, because at the distance they require to focus, the magnification is too small. You can read more about telephoto and closeup filters in my comparison of lenses and closeup filters with true macro lenses.
The Fuji S602 for example has a maximum zoom of 210mm and at this focal length the lens requires a minimum distance of around 100cm to focus. At that kind of distance, the magnification is not sufficient for close up photography. A close-up filter or macro lens is able to solve this problem by reducing the distance that the lens requires to focus. When this distance is reduced, the magnification is increased.
Apart from close-up filters there are several other kinds of equipment for making the image the required size. These range in price from £15 for a close-up filter to £1,500 for a top quality macro lens, although lenses are generally around the £400 mark.
A dedicated macro lens might be optimised to provide its best performance at a magnification of 1:1. Some macro lenses, like the Canon MP-E 65 mm f/2.8, can achieve even better magnification, up to 5:1 macro, bringing the structure of small insect eyes, snowflakes, and other minuscule but detailed objects into striking focus.
You can also place an extension tube between the camera body and the lens. The tube has no glass in it; its sole purpose is to move the lens farther from the film or digital sensor. The farther the lens is, the closer the focus (and the bigger the magnification). Also, less light will reach the film or sensor, therefore a longer exposure time will be needed. Tubes of various lengths can be stacked together, allowing for increasing levels of magnification while working distance decreases. With tubes attached, the camera will often lose the ability to focus to infinity. A bellows attachment between the camera body and the lens will work in the same way, except that a bellows extension is adjustable.
You can also attach a telephoto extender between the camera body and the lens. A 1.4x or 2x teleconverter gives a larger image, adding macro capabilities. As with an extension tube, less light will reach the film or sensor, therefore a longer exposure time will be needed. However, working distance remains the same as without the tele-converter.
Depth of field is an important consideration in macro photography. This makes it essential to focus critically on the most important part of the subject. Parts of the subject that are even a millimetre closer or farther might be noticeably blurry. The depth of field can be increased by using a narrower aperture (f/11 or greater).
The cameras macro program is all but useless, as it serves no purpose other than restricting the optical zoom range. I almost always use manual mode for close-up work as it allows me to adjust the aperture and the shutter speed myself.
Also using the lowest ISO setting possible will reduce the amount of noise, and create a higher quality print, but if you are using closeup filters or extension tubes you may need to increase the ISO to improve shutter speed.
Using a flash will illuminate the subject well, reduce shutter speed and increase the overall quality of the image, but you may only get one shot using the flash as most insects will flee. In-built flashes will almost certainly be of no use - you will need a dedicated macro ring flash which will evenly illuminate the subject without the camera body casting a shadow.
This requires lots of patience and practice. Don't be too disappointed when your first images are blurred and out of focus. That is if the insect stayed still long enough to photograph. Insects are very cautious animals and will flee at the first sign of danger. It takes a lot of practice to approach an insect without it running away.
Bit of a no brainer this one... essential for all photographs is to focus on the subject, but for macro photography it is very difficult. At close-up the depth of field is reduced to a few mm or less, so once the camera has auto-focused, any hand movement, or movement of the subject, will result in an out of focus shot. Use a shutter speed of at least 1/100 or 1/lens focal length, to minimise hand shake, and take the picture as soon after auto-focus success.
I have also found some success at setting the focus to the closest and moving the camera itself back and forth until the subject falls into the "sweet spot". You can also get a macro tripod which has a focusing rail which does exactly this.
A good background should be smoothly blurred-out. The effect is not difficult, only requiring a higher zoom with a lower diopter. The further the subject-to-background distance, the more blurred the background is.
The background should also make the subject stand out, so plan your shot well. Photographing a spider against a complex background will make it difficult to see, same goes for photographing a green insect among leaves.
This is the final framing of the image and presenting it. Try and get the insect to face the camera at an angle (not directly on), or a side view. Try to apply the rule of thirds to all your photographs. These simple points will enhance the image no end. Sometimes it is not possible to apply the rule of thirds in the field, you need to focus and snap as quickly as possible, before the subject flees. In these cases you can crop images using Photoshop or similar.
I hope you have found this interesting enough to give it a go, and let me know how you get on! You can view my gallery of insect macro photographs in my gallery.