Outline:
1. Gadgetry
2. Ant Photography Tips
3. Some Useful Links

First, the bad news. 

      Macro photography of any kind is expensive. While a skillful artist can make fantastic general photographs using as little as a home-made pinhole camera, the unfortunate fact is that macro photography requires a certain amount of equipment to achieve sufficient magnification beyond the abilities of a basic photography set-up.  This equipment costs money. Often a lot of money.  And unless you regularly take thousands of photographs, digital equipment only makes macro photography more expensive.  So don’t say I didn’t warn you, months from now when you find yourself destitute, living in the street, your savings turned into lenses and flash units. 

Now the good news:

      Digital makes everything easier, especially macro photography.  With digital equipment we gain instant verification of focus and exposure in the field, complete control over our own image processing, and we can take advantage of innovative camera designs that are a great deal more flexible than film cameras. What's more, image quality from the best digital cameras now matches that of 35mm film, so the only cost of going digital is the price tag.
      My digital experience covers two very different photographic systems: a mid-grade consumer digicam and a digital Single Lens Reflex (SLR) camera.  These each have advantages and disadvantages, which I will discuss below. 

Digicams: The Nikon Coolpix 995.

     Digicams are great fun. They are small, self-contained point-and-shoot cameras loaded with features from video recording to on-board color correction and image sharpening.  Most are designed as idiot proof automatics, but also allow full manual control over focus, aperture, and shutter speed.  They’ve been freed from some of the design constraints of traditional film cameras, making photography easier and more flexible than the point-and-shoot film cameras that they replace.  Some of them take macro photographs that are simply fantastic.
      My digicam is a Nikon Coolpix 995.  The 995 is part of a long line of Nikon cameras that excel at macro.  The 995 has since been discontinued, but its successor, the Coolpix 4500, is a similar camera that has slightly improved resolution and is a bit smaller and lighter.

What I like about the 995:

• Macro capabilities. The Coolpix lets one get within 2 cm of the subject, which allows for powerful magnification. Achieving similar magnification with an SLR system requires order-of-magnitude increases above the 995 in system bulk and weight. 
• Swivel design.  The lens part of the camera can swivel independently of the camera that has the preview LCD, so I have the freedom to frame a shot in the LCD without the bodily contortions needed to peer through a viewfinder. I can hold the camera at waist or ground level for shots of insects on low vegetation or the ground.

• Chromatic aberrations. Little purple fringes at the edges of high contrast areas. Apparently, this is a problem with most digicams, a function of how lens aberrations interact with the sensor chip.
• Shutter lag of a second or more between the time the shutter button is depressed and the camera takes a photo makes well-timed action shots difficult.
• Low (3 Megapixel) resolution. The number of megapixels determines how large an image can be reproduced. 3 megapixels is fine for small prints, but anything above 8x11" will pixelate.  Bear in mind, however, that 3 megapixels is overkill for web/powerpoint use.

Ectatomma tuberculatum, Paraguay.  Nikon Coolpix 995. 1/30sec, f/6, natural light.

Manica bradleyi, California.  Nikon Coolpix 995. 1/2000sec, f/11, w/flash.

Digital SLR: the Canon EOS D60.

     Digital SLRs are little more than traditional film SLRs with a digital sensing chip instead of a film back and an LCD screen that allows review of images stored on the camera's memory chip.  Photography with digital SLRs is not terribly different than film photography, except that images can be reviewed immediately in the field.  These are not self-contained units, as they require additional lenses to complete the system. This can be a big plus if you are already invested in a film SLR system and already have lenses, flashes, and other accessories. 
      I have a Canon EOS D60. This machine has recently been replaced in Canon's line-up with the similar Canon EOS 10D, but my comments should apply equally to both. I also have a pair of macro lenses, the Canon EF 100mm f/2.8 USM Macro Lens for general macro and the Canon MP-E 65mm 1-5X Macro Lens for more extreme close-ups (really useful for ants!).

What I like about the D60:

• Image quality. Amazing!
• Flexibility in optics. Lenses are interchangeable, so I have access to all sorts of different lenses for different purposes. Canon makes some excellent lenses, including  fantastic macro lenses like the MP-E 65mm 1-5x.
• No shutter lag. Unlike the 995, photos are taken the instant the shutter button is depressed.

• Size and weight. This camera is a brick. It is not a simple little thing that I can slip in my pocket and take hiking.  Add in lenses and flash unit and the system becomes very cumbersome.
• Sensor dust. Interchangeable lenses expose the sensor to the environment every time I change a lens.  Dust builds up on the sensor over time, leaving black specks on the photos that have to be cleaned in photoshop.  Cleaning the sensor is not too difficult, but it is inconvenient.
• No LCD preview.  This camera works just like a film SLR, and the mirror that serves the viewfinder sits in front of the sensor until the photo is taken. This means that pictures cannot be previewed in the LCD. So it's back to lying in odd positions on the ground to line up shots in the small viewfinder. Also, the image review feature is not as good as it could be, although I hear that Canon has improved this in the new 10D camera.

Camponotus hyatti, California. Canon EOS D60, Canon MP-E 65mm 1-5x f/2.8 Macro Lens. Diffuse flash, 1/200sec, f/13.

Stenamma dyscheres, California. Canon EOS D60, Canon MP-E 65mm 1-5x f/2.8 Macro Lens. Diffuse flash, 1/200sec, f/13.

     As a general comment about both digicams and digital SLR's, the listed price of the camera is short of what you will actually spend.  Most cameras ship with minimal memory and a single battery. Realistically, you will probably need to acquire additional memory, extra batteries, a camera case, a lens cleaning kit, and protective filters.  And that's just the beginning- you might want to invest in a good photo inkjet printer, better imaging software, a tripod, a CD burner for image storage, web server space to display your new photos, plane tickets to exotic, photogenic locations...
 

Ant Photography Tips

     Ants in the field are difficult subjects compared to most insects. The crux of the problem: small objects like ants need lots of magnification to fill the frame.  High magnification results in a very narrow depth of field (for example, when the head is in focus the rest of the body isn’t). Narrow depth of field can be overcome somewhat by decreasing the aperture, but in order to preserve the proper exposure with a small aperture we need to keep the shutter open longer.  Longer shutter speeds mean that movements will translate into blur on the resulting photograph. So we either get an ant that is blurry because the depth of field is too narrow, or an ant that is blurry because it moved during the ½ second that the shutter was open.  The smaller and faster the ant the more difficult the photo becomes. A good shot of Forelius is darned near impossible! 
      There are two solutions to this problem.  The first is to find immobile ants. (Unfortunately, Basiceros aren’t available to most of us.)  Some species will freeze briefly when alarmed, every once in a while they freeze for long enough to line up a shot or two.  Ants can also be persuaded to sit still when feeding from a drop of sugar water.  The resulting photographs appear remarkably natural, as the ants are bathed in ambient light. But, this strategy leaves a lot in the hands of chance, and presumably we don’t want all our ant photos to be either of ants drinking or of ants looking alarmed.
 

     The second option is to use a flash.  Flash increases the amount of light and decreases the amount of time that the shutter needs to remain open for a proper exposure.  With flash we can get a crisp photo of a moving ant while still preserving depth of field. The drawback, though, is that photos rarely look natural with flash.  The light can be harsh, producing glare on shiny insects.  Spot flashes leave dark, distracting shadows, while ring flashes produce spooky, unreal images with no shadows at all. These difficulties can be solved with the use of a diffuser, or by bouncing the flash off of a white sheet of paper held above the ant. The flash that I use is the Canon MT-24EX Macro Twin Lite, but many other flashes work fine. 

There are many ways to take ant photographs, but here is a general formula:

1. DO NOT USE THE CAMERA'S AUTOMATIC SETTING.

2. Select the lowest ISO equivalent setting available. In most cameras, this will be ISO 100 or lower. Higher ISO equivalents will introduce noise into the picture, and while they allow for faster shutter speeds they don't result in smooth images.

3. Manually focus the camera for the desired magnification. Auto-focus has a very hard time with the narrow depth of field in macro subjects and rarely focuses where it should.  Instead, set the focus to a distance near the lens (e.g., .04 m in the Coolpix 995) and move the entire camera back and forth to bring the subject into focus. If you are using a digicam with zoom, set the zoom to about mid-range.

4. Set the aperture for maximum depth of field. In the Coolpix, this will be around f/10-f/14, depending on the zoom. In a dSLR, this setting will depend on the lens.  For the Canon MP-E 65mm 1-5X lens, this will be f/13-f/16.  Be wary of stopping down too far in the dSLRs, because small apertures will cause a lack of sharpness.  The trick is to find the "sweet spot" where depth of field is relatively high but the picture is still acceptably sharp. 

5. Pointing the camera at the subject, use the light meter to set the shutter speed for the appropriate exposure.  For most conditions, the shutter speed will end up being pretty slow: 1/2 second to 30 seconds depending on the ambient light.  If you've got a stationary ant and a stable camera, you are ready to take the picture.

6. If your ant is moving, or if you are worried about camera shake blurring the picture, use flash and set the shutter speed higher, to at least 1/125sec. How fast the shutter speed can go depends on your particular camera and flash unit. 

7. Shoot away.  Check the resulting photograph on the LCD.  Is it in focus? Is it too light, or too dark?  Is the ant doing what you wanted it to? 

8. Keep shooting, after making any adjustments to the settings.  Film is free in digital, so you may as well shoot until your trigger finger gets tired. 

http://www.mplonsky.com/photo/article.htm- Mark Plonsky's insect macro tutorial.  Mark is a master of close-up insect photography and his gallery is well worth a visit.

http://www.dpreview.com- complete camera reviews, equipment discussions, and more.

John Shaw's Close-ups in Nature- a very useful book on the techniques of macro photography.

Ants of Arizona- Dale Ward shows what can be done with a Nikon Coolpix 990.

Myrmecos.net- my own gallery of accumulated ant and other insect photos.