New digital camera? Good stuff. But hold your horses: you should learn how to use three simple software tools, which you can apply to almost all your photos and which is almost guaranteed to improve them. None of them takes more than a few seconds and they can enhance the look of the dreariest shot immensely. Those steps are known as levels, saturation and sharpening.
So load up the photo-editing software that you’ve no doubt got lurking on your hard disk somewhere. If you haven’t got any, download a nice free copy of the GIMP, which despite the name is a free photo-editing package, not something your ISP should be blocking. We’re going to use GIMP 2.6 for the shots here. Most other photo editors – including Photoshop Elements and Photoshop CS4 – are more or less identical as far as the way these basic tools work.

Levels
This can be the single most effective edit you can apply to a photo, particularly one that’s not been brilliantly exposed. If the exposure isn’t perfect – and sometimes even if it is – the tonal range of a digital photo can be clumped into a narrow area. In a digital photo, pixels are represented as numbers, so the idea is to expand the tonal range so it covers as much of the numeric range available as possible. The effect of expanding the range is to give shots much more punch and contrast. It’s easier to do than to explain, see head to the GIMP and select Tools | Colour Tools | Levels.
In the Input Levels box, you’ll see a lumpy graph. This is the histogram of the image, which shows the number of pixels in the image at each intensity: pure black on the extreme left, up to pure white on the far right, with the greys in between. The higher the hill the more pixels at that level of brightness. If the ‘foothills’ of the graph on either side don’t reach to the edges, the image is ripe for a bit of levels tweaking.

Drag the left-hand arrow beneath the histogram to the point at which the foothills begin on the left, and then drag the right-hand arrow on the right to the point at which the foothills begin on the right, thusly:

You may find that when you drag the right-hand arrow in, things get excessively bright: it depends on the image. If it does, drag the arrow back a little bit. When you hit OK, the tonal range of the image is expanded by pulling dark greys down to black and off-whites up to bright white.
If you’ve done it right, the difference between the before and after versions of the images should be quite marked. With a badly exposed image it can look as if a veil has been lifted from the shot and everything is much clearer. Here’s a genuine example of a before and after, showing the difference it can make – levels was the only edit we applied:

Hue/Saturation
This is where you can cheat a little bit and make your pictures better than real life by artificially enhancing the colurs. Levels gives your images punch and increasing the saturation – in other words the richness of the colours – can add nicely to that effect. The key with this one – as with most effects – is not to overdo it. The effect itself is simple enough to apply in GIMP – just pop to Tools | Colour Tools | Hue/Saturation. Don’t tweak the Hue or Lightness sliders – just tweak the Saturation slider up a bit.:

If you go past 15 you’re probably overdoing it: between 5 and 15 is usually the best range to give the colours a lift:

Sharpness

If you resize a photo down to web size, or you want to print it off at maximum resolution, you’ll find that applying a sharpening routine can really enhance the detail. Somewhat unintuitively, the most effective sharpening tool is called ‘unsharp mask’. In GIMP you’ll find this clever widget in the Filters | Enhance | Unsharp Mask menu.

Before you apply unsharp mask, always zoom your shot into 100%, otherwise you’ll overdo it and not realise. In GIMP just go to View | Zoom and select 1:1 (100%). Again, being sparing is the key to avoiding nasty artefacts. For a print-size (in other words high-resolution shot that you’ve not resized) try a Radius setting of 1.0, Amount at 0.50 and Threshold at 0. For a photo that you’ve downsized for the web – apply the sharpening after the resize – try being a little bit more aggressive. Experimenting is the key but always bear in mind the golden rule of not overdoing it:

And that’s it – these are the three essential adjustments you should make as a matter of course to all your shots. After a bit of practise each step will take only a few seconds, and it’s very well worth the effort.