This month's column is the first of a series that will provide a step-by-step tutorial for restoring photographs. The tutorial will draw from tools covered in previous columns, and add some new tips.
RESTORING VS. ALTERING
If you are restoring a photograph, you should consider your ultimate objective. Are you attempting to recreate the photograph as it looked when it was first taken, or are you going to significantly alter the image? This poses an important question that may influence the way you restore an image. Simple techniques will rarely harm the look of an image; however, some of the sophisticated filters and tools available on a PC can make some photographs almost unrecognisable in just a few clicks.
At other times, the effect may be more subtle. For example, a photograph may have charm because it has faded to a light sepia colour and has worn edges. Restoring it to full black and white may change its character in such a way that it no longer seems so 'old'. Most photographs have strong emotional links, and being overzealous in their restoration can, in the eyes of the owner, ruin the picture.
The easiest rule is to decide on the outset whether you are going to restore a photograph or use it to create a new image. Set yourself a list of tasks and try to follow them. This list may include items such as remove scratches, centre the main subject and remove red-eye.
If you have a hard copy of a photograph, then the first step will be to scan the image (last month's column dealt with scanning and resolution). In summary, if you have at least a 200MHz PC with 64MB of RAM, then scan your images at 600dpi (or if the maximum optical resolution of your scanner is less than 600dpi, then use its maximum setting). When scanning pictures larger than 8x10in, drop the resolution to 300dpi. Also try to scan a few extra millimetres around the photograph, as this may be needed during restoration.
Since you will be editing the picture, you should save the image as a TIFF file. This will make it fairly large (10-30MB), but this is only a temporary working file. Saving in JPEG format will cause some data to be lost each time and this will make editing more difficult - particularly if you open and close the file many times. You should also make a copy of the scanned file. In case something goes wrong, you can then go back to the original file. It is also a handy reference point so you can see how your alterations are progressing.
When editing an image, one of the first things most people do is trim it. In fact, this should be done much later in the restoration process. Trimming can discard information that may be useful if the image is creased, torn, marked or needs to be rotated. Even if you are certain of the trim you want to make, it is still prudent to leave some extra space until editing is complete (we will return to trimming towards the end of this restoration series).
You will save a lot of time if you can set the image so it is level in the scanner. There may be times when this is not possible and you may need to rotate the image (this is a common problem if the photograph was taken on a slight angle).
As you rotate an image, the space left behind will be filled by the current background colour, so make sure that you have selected a suitable colour. Usually it is wise to use black, white or transparent - see the image on this page, which has a red background. If a large border was left when scanning, it can be easily trimmed without losing too much of the picture.
The image at left shows how problems occur if you scan an image at an angle and trim it too early in the restoration process. This image was trimmed first, but when it came time to rotate the photograph by 3ø so that the building was level, new artefacts were introduced (seen here in red). Using the trim tool a second time to remove the unwanted background will also mean sacrificing parts of the building and ruining the frame of the image. So, remember to leave the trimming until later stages. Red is shown here for effect, but a better choice of background colour, like black, will reduce the impact and allow a less severe cut.