They say that the difference between an average photographer and a great one is a few thousand miles of film. Even today, when digital cameras no longer use film, the idea behind this maxim still holds true.
Digital cameras have improved immensely since they first entered the marketplace over a decade ago. The average memory capacity is higher, which means that many more pictures can be taken at print-quality resolutions. They come with features that used to be exclusive to optical film cameras and a few entirely new ones: such as being able to see the framed image exactly as it will appear in the final picture. Best of all, digital cameras are now much, much cheaper.
None of these will keep you from accidentally moving the camera at the critical moment, or placing your thumb over your picture just as you press 'click'.
Getting the most out of your digital camera consists of two parts. First, purchase a camera which best meets your needs at your cost threshold. Second, learn how to best make use of its features to take the pictures you want.
IDENTIFYING YOUR NEEDS
What kind of pictures are you most likely to take? Are your subjects likely to be constantly moving, or are you more of a static photographer? Do you want high manual control over the various controls, or do you prefer auto-focus and automatic light compensation? Do you need print quality, professional quality, or will you be sharing your pictures on Facebook? How much card memory will you need to cover all the pictures you are likely to take until you can transfer them to your computer?
If you will be taking many pictures of moving subjects, you may want to keep in mind that an automated camera may be slow to focus at low light. An image-stabilised lens can compensate for any slight movement you might make while taking the picture. A larger digital sensor element is capable of higher pixel resolution. (Some professional-quality larger sensors also make use of a different technology, known as 'full-frame': but here you are looking at some significant price jumps.) At some point most photographers will want close-ups, making a good-quality optical zoom a highly useful part of the core package. Make sure it is an optical zoom and not a digital zoom, since the latter will only magnify the pixels, not bring the original image 'closer' in the same manner as a telephoto lens.
If you take many pictures while you travel, you will definitely want to consider the memory size of individual memory cards. This holds especially true if you wish to take professional quality pictures, which take up a shocking amount of memory. On the other hand, at the 72 ppi (pixels per inch) standard resolution of Internet display, many memory cards available today should be able to hold dozens of pictures. Memory cards now hold up to 16 gigabytes of memory. Even so, if you want to print out some or most of your pictures, you will almost certainly want to take at least one extra memory card with you on your travels, and probably more than one.
Keep in mind also the resolution of your printer. There is little point in taking pictures at a higher resolution than your printer is capable of showing. The typical inkjet printer prints at 300 dpi (dots per inch); while professional quality begins at over 1000 dpi (dots per inch). The two units of measurement are not interchangeable, but dpi only becomes relevant when an image is to be printed out.
Another useful feature is a pre-flash that almost completely eliminates the red-eye horrors of the past. Most good-quality digital cameras now come with this feature.
USING THE CAMERA
Some of the techniques for taking good-quality pictures with a digital camera are exactly the same as those for using an optical film camera. These fall into three general categories: frame, lighting, and depth of field. For automatic cameras, only the framing will be immediately relevant, since the camera itself will compensate for the other factors. However, some automatic cameras can be sluggish in responding to low light, something you will want to keep in mind when choosing your pictures.
These three factors can be easily controlled with manual settings, but learning exactly how to adjust aperture and shutter and frame is an ongoing study in which there is no substitute for practice. However, a few simple rules of thumb will get you solidly started. In general:
1. The deeper your subject field, the wider your aperture should be. This allows your foreground and background to both be in focus.
2. The faster the subject, the quicker your shutter speed should be; while the lower the light, the longer to set your shutter speed. However, the longer the shutter speed, the more likely your picture will turn out blurred as a result of your own motion: unless your camera has an image-stabilising lens. (To catch fast-moving subjects at low light is an ongoing challenge, even for professionals.)
3. Balance the elements of your picture. Imagine a centre to your picture field, then 'weigh' the elements around it until they balance each other against your imaginary centre. Balance also your foreground against your background. If you are taking a deep landscape or sunset picture, try to use a nearby element to give perspective.
4. Avoid the temptation to take 'busy' pictures. Pictures with only one or two elements tend to work much better.
5. Always take the extra moment to check to make sure you have not accidentally cut someone's head off!
For digital cameras specifically, it is always a good idea to test your white balance against different types of light. Artificial lighting especially can sometimes make your whites turn yellow or blue. This too may be an automatic setting, or you may be able to set your camera for sunlight, shade, electronic flash, fluorescent lighting, or tungsten lighting. You can test this easily by using a white card under the lighting in question, and letting the camera figure out how to make it look properly white.
Above all, be prepared to take the time to familiarise yourself with your camera. Read the manual, experiment, remember what you did in the pictures you really like, but especially in the ones that didn't come out so well. (It may help to take notes at first.) Few of us are able to take a camera out of the box and immediately take perfect pictures ... but with time, we can come just a little closer.