Our society has expertise in restoring old photographs. Some photos have simply faded over time but many have picked up significant blemishes from dust, stray hairs, staining or a myriad of other process that have damaged the picture over the years. Interestingly, even some professionally produced images such as some postcards in the normally excellent Rose series, were reproduced in a rather slapdash fashion (see section below) and carry distracting blemishes.
Thankfully, there is now a great deal that can be done by image processing the digital scans of the original images, remembering of course that the processed image is no longer a faithful reproduction of the original. We process images using non-destructive methods that always preserve the original scan and save the edits so that any or all steps can be unwound should future improvements in image processing require access to the original images.
Analogue Photography
Before the advent of digital photography, images were recorded on photographic emulsions, carried on either transparent plastic (film), or in the very early days, glass plates. These film or plates recorded a negative of the image and final prints had to be reproduced by shining light through the film or plate negative onto a piece of photographic paper, which also carried photographic emulsion. That process also created a negative image, but because the light creating it was shining through the original negative, the result was a negative of a negative, which is positive image. The process had to be carried out in near darkness and involved several dishes of chemicals. In all the palaver, there was ample option for images to pick up blemishes. Mostly these take the form of fingerprints, dust and hair blemishes on the images that are ‘baked in‘ to the postcard or photograph, no matter how well it has been looked after since it was printed.
Examples of Blemishes & Restoration
Fingerprints and scratches
The image of Ilkley Heights in Ferny Creek is an example of a badly printed postcard. When printing, the negative was scratched and had bad fingerprints. It proved difficult to improve but the result is better than the original. The result is below.
Major Restoration
Most images only require simple processing to clean them up, but some require much more complex work. A badly damaged example is the photo below of Mountain Grange in Kalorama. The right-hand edge was seriously damaged and in the absence of extra information could not be recreated. It did not appear to have much of interest, so that was cropped out. When the photo was taken, photographic emulsions were much less sensitive than they became later and so the exposure time was long. So long in fact that the tree on the extreme left and the tree fern in the damaged part of the photo on the right, both of which must have been moving in the wind, were subject to motion blur due to long exposure. The effect is clearly visible in the original scanned image below.
The results of the restoration are shown below.
Staining
Shown below is a before and after comparison of a photo with colour staining. The brown stains at top middle and blue fingerprints at bottom right are removed on the processed image but the tint has also been removed, and the result is a pure greyscale image.
Descreening
Screening is an effect created by some methods of photo printing. It is not generally very noticeable but most certainly becomes an issue if the photo is blown up to a large size or if it is subsequently printed at a different resolution when it can lead to nasty Moiré patterning effects. Descreening, is a filtering process that smooths out and removes the patterning appearance of halftone dot patterns in affected images. The effect is shown in the two zoomed in images of St. Michael’s church Kalorama below.
The full-size images are shown below.
Print vs Negative Scanning
If available, scanning negatives (with the correct equipment) almost always yields better results than scanning a print. The difference is illustrated below. Note that the contrast and clarity of the negative scan is significantly improved over the print scan. In addition, the scan of the negative yields a much wider view of the scene in Tremont. The cropping of the image probably occurred during the enlargement process when the print was created. Note also that there was some optical distortion, probably in the enlarger which causes the middle of the two images to be misaligned despite the edges being closely aligned.
