Digital cameras: Photo manipulation

A swoosh of an air-brush can bring even the dreariest images to life. Charles Arthur learns how

Before digital pictures, there wasn't a lot you could do with your photographs besides frame them. Unless, that is, you were the sort of person who was happy to play with sodium thiosulphate beneath a red light - in other words, work in a darkroom.

Now, though, the "digital darkroom" has taken over, and millions of people are able to adjust photos and create completely new versions without messy chemicals.

Though many people are content to simply take a photo with their digital camera and print it out, a little effort with a photo-editing package can work wonders. Digital cameras often don't necessarily produce beautiful pictures straight away - but with some effort you can make a poor picture much, much better.

There are plenty of photo-editing packages around. But the rule for improving pictures, or making Christmas cards and posters, is always the same: make a copy of your picture, and work on the copy. Then, if you mess it up, you'll still have the original to start from.

So, you're working on your copy. The first thing to consider is: are the white things in your photo actually white? "Colour casts" are common, caused by things like tungsten lighting (which gives a bluish tinge) or insufficient light inside (which gives a yellow-brown tinge). Colour correction consists of finding something that you know is white, and fiddling with the colours of the photo until it looks white on the screen too.

Next are "hue" and "saturation". Hues are the colours, and saturation indicates how many colours there are in the picture; a black-and-white picture has little saturation. You usually want more, because it makes the scene more vivid. There are plenty of tutorials online for every package if you want to learn from the experts; alternatively, experimenting is an interesting, but time-consuming, way to teach yourself.

Now, do you want to include everything from your picture? "Cropping" can change what you see dramatically, by getting rid of extraneous detail and concentrating on the important elements. With film, cropping had to be done with scissors - and you only got one chance to get it right. Remember, you're working with a digital product, and a copy at that, you can try different tricks to your heart's content.

Programs like Adobe's Photoshop Elements offer many tools for cleaning up pictures and removing unwanted elements. The most commonly used is called "unsharp mask", and comes from a real darkroom technique (which used one sharp and one blurred negative together). Unsharp Mask - usually called "USM" - sharpens edges by emphasising the contrast between nearby pixels if they have different contrast. It's a neat tool, but as Bruce Fraser notes on the website Creative Pro, "it's a powerful tool, but it has two disadvantages - it sharpens everything, including noise; and it's 'destructive' - its changes are made directly to the image data." He suggests creating a "layer" copy, applying unsharp mask and other filters to that layer, and melding the two layers to create a better result.

The bigger you're making the picture you're going to print out, or the longer you're going to be looking at it (for example in a poster or calendar), the more care you need to take in the editing. Nobody needs to know that the original was a washed-out mess; remember, what you see on the front of magazines every week is not how it looked in the studio; teeth will have been whitened, blemishes removed, even legs lengthened before a cover hits the newsstand. So be patient.

The fact that better pictures are in reach also means that you can make film posters - using montage effects to blend photos and add text - or calendars or Christmas cards. Many programs will help you directly with the latter; there's a website that will allow you to create a movie poster in as much time as it takes to type your name (http://flagrantdisregard.com/flickr/poster.php).

Once you've got the taste for photo-editing, you may find it addictive. There are plenty of stand-alone programs and plugins that can give all sorts of fascinating effects - turning your photo into a cartoon, or making it resemble a watercolour or oil painting - see the website http://www.dizteq.com/paint effects.htm, or try Canvas, at www.deneba.com, or XnView, a cheap image editor and converter whose filters various features include "oil effect" (http://perso.wanadoo.fr/pierre.g/xnview/enxnview.html). But in the end it's all down to your imagination. The nicest thing about working with digital pictures? That nowadays the darkroom can be your sunny living room.

PHOTO-EDITING AND SOFTWARE PACKAGES

Adobe Photoshop Creative Suite 2 (Adobe)
Top of the range in flexibility and power - most commercial images you see are created with it, but also in price. Still the choice of professionals, but possibly too costly for the average mortal.
Availability: PC, Apple Macintosh
Price: £400 retail; educational discounts available

Adobe Photoshop Elements 4 (Adobe)
A cut-down version of Photoshop, retaining much of its elder sibling's flexibility, but without some more powerful tools (such as "cloning"). Offers three levels - beginner, intermediate, expert. Still, not strong on guiding the user. An excellent budget choice.
Availability: PC and Apple Macintosh
Price: £60 retail; often bundled with hardware

Corel Paint Shop Pro X (Corel)
A worthy competitor to Adobe, with a neat "Learning Centre" interface for common tasks (like retouching, collages or effects). Includes an "Object Remover" for getting rid of unwanted things , and a "clone" tool for duplicating those you do want. For beginners to advanced users. Includes the picture organiser Photo Album 6.
Availability: PC
Price: £75

Microsoft Digital Image Suite 10 (Microsoft)
Really two integrated programs in one - a Library, for organising photos, and Pro 10, for editing. Task-based rather than tool-based, meaning it wants to know what end result you're after, rather than giving you a set of tools to play with. If what you want to do is on its list - Touch Up, Format, Auto Fix, Add Effects - you'll be happy. Otherwise, you'll do better with Photoshop Element or Paint Shop Pro, which are tool-based.
Availability: PC
Price: £27

Roxio Photosuite Platinum 7 (Roxio)
An organiser and editor using a streamlined interface. Fixes red-eye and blemishes quickly, and can guide you in creating greetings cards, slideshows or video CDs. Better for novices than experienced users, who may want more fine control.
Availability: PC
Price: £50

GIMP
Aims to be a free competitor to Adobe Photoshop. Not as polished as paid-for programs like Photoshop or Photoshop Elements, but packs a lot of power for those with plenty of patience. Those with big ambitions, broadband and a limited budget may find it useful.
Availability: PC, Mac, Linux
Price: free download from www.gimp.org

Picasa (Google)
More of a photo organising and sharing program, but includes some standard editing functions, such as the ability to remove red-eye and perform simple adjustments to the colour balance of a picture. One neat feature: you can undo mistakes long after you've finished working on a photo. Perfect for beginners. Overall, a great introduction and good for getting your digital portfolio in order.
Price: free download from www.picasa.com

iPhoto (Apple Computer)
Mostly a photo organisation suite, but also has controls to remove red-eye, do simple retouching, apply a few filters and adjust colour levels and saturation. Can create photo albums directly. Simple to use, but limited in some key respects; cannot, for example, create montages. Part of the "iLife" suite of programs; not available separately. Comes free on new Apple computers.
Availability: Apple Macintosh only
Price: £49 for single or £65 for a "family pack" usable on up to five different Apple computers in a home.