BOOT CAMP 265 (04/03/03)

DIGITAL PHOTOGRAPHY part 5

In the final part of this short series on digital photography we’re looking at some of the things you can do to your photographs once they’re stored on your PC but before we begin, commit to memory the golden rule of image manipulation: never work on your originals! If you are going to fiddle around with a picture open it in your chosen editing program and before you do anything else go to Save As on the File memory and give it a new name. That way you preserve the original and it doesn’t matter if you change your mind or make mistakes, which on some programs may be difficult or impossible to undo.

There are a few more commonsense points to bear in mind. Almost everything you do to a digital photograph on a PC will degrade the image to some extent so the trick is to do as little as possible. Practice editing ‘in-camera’ and avoid the need to enlarge or rotate an image by getting closer to your subject and holding the camera level.

Most digital cameras come bundled with a basic picture-editing program but if you want to get the best out of your camera it’s worth investing in some good quality software. Unless you are a professional there’s no need to go overboard with serious and expensive applications like Adobe Photoshop, which in any case have far more features than you‘ll ever need and involve a steep learning curve. Equally, for straightforward picture editing avoid ‘fun’ programs with lots of templates and toys for mangling and distorting pictures.

Three good programs for home users are Paint Shop Pro (fully functional 30-day trial at: www.jasc.com), Photoshop Elements (trial version at www.adobe.com) and Digital Image Pro (more info at: http://pictureitproducts.msn.com/default.asp). Beware, the downloads are quite large (30 to 100Mb) so only get them from the web if you have broadband or are very patient…

What these programs have in common is a good selection of tools that let you do the most common jobs with a minimum of fuss. These include cropping, (cutting out unwanted areas of a picture), adjusting colour, brightness, contrast and sharpness, removing red-eye, retouching and repair (remove scratches and so on), enlarging and reducing, rotating the image, and copy move and paste parts of the picture (to remove or replace unwanted subjects or objects). They can all handle a wide variety of file formats (for both opening, saving and converting images), and they make it easy to prepare your photographs for web pages, email or printing.

There’s not enough room here to delve into the specifics of each program but we can talk about some general principles. Follow a simple routine and don’t try to accomplish too much in one go. Always begin by straightening or realigning the picture (if it needs it) with the rotate tool then crop out any unwanted portions of the picture, though remember this can have an effect on quality if you want to maintain a particular print size so use it sparingly; don’t forget to save frequently. Next, correct any errors in colour, brightness and contrast then you can set about repairing the defects. 

When working on small details choose an appropriate magnification or zoom setting. (By the way, this has nothing to do with the size of the picture when it’s printed, just the way it’s presented on your monitor screen). If you want to remove spots or pimples from a subjects face, zoom in close, until you can start to see the individual pixels and use a ‘clone’ or ‘airbrush’ tool to copy colour and texture from a nearby area of unblemished skin, then zoom out to check the result.   

Most programs have an automatic red-eye removal tool but I prefer to do it the old-fashioned way, by hand and the results often look more natural. Simply zoom in on the affected eye, use the program’s manual section tool to carefully outline the red area then use the colour saturation control to reduce the colour level in the selected area to zero.

When you’re happy with and saved the file you can prepare your image for its intended purpose by resizing and resampling. If it’s to be used to illustrate a web page or document you can decrease the resolution significantly to make the image (and file) smaller and more manageable. For emailing increase the compression ratio, which also reduces the size of the file but without changing the dimensions of the picture or sacrificing too much detail and for printing adjust the image size and resolution to suit the printer and paper.

We’ll finish off with two general-purpose tips. Photo editing can involve a lot of repetition so familiarise yourself with your program’s keyboard shortcuts. Ones that you should definitely remember (common to pretty well all Windows applications) are: Ctrl + C (Copy), Ctrl + V (Paste), Ctrl + Z (Undo) and Ctrl + S (Save).

A lot of retouching techniques require a steady hand so the last thing you need is a jerky mouse pointer making it difficult to make small or precise adjustments. If you have a ‘ball’ type mouse give the rollers inside a spring clean or change to an optical mouse. You might find it easier to slow down the pointer speed; go to Start > Settings > Control Panel > Mouse > Motion and adjust the slider, to make it more controllable.

Next week – Word tips and tricks

JARGON FILTER

 CLONE BRUSH

Tool for copying an area of a picture, to replace colours and textures

RESAMPLE & RESIZE

Two techniques for altering the dimensions of an image, in general resampling is better for photographic images, resizing works better with simple graphics

RESOLUTION

The number of picture elements or pixels that go to make up a digital image, measured in dots per inch or dpi. A resolution of 72dpi is sufficient for web images and documents whilst 300dpi or above is required for good quality photographic prints

TIP OF THE WEEK

The beauty of modern film and digital cameras is that they are so easy to use, just point and shoot. Nevertheless, a lot of photographers still like to get their hands dirty, but you can quickly get bogged down in the mathematics of lenses, exposure times, shutter speeds and depth of field calculations. The excellent Calculators On-Line web site contains a whole section devoted to specialist photographic calculators at:

http://www-sci.lib.uci.edu/HSG/

RefCalculators1.html#CAM-PHOTO,

but do have a look at the top of the page, where you’ll find links to more than 16,900 web calculators, covering everything from Aquaculture to X-Ray Interactions.