This is the first in a series of four 'background information' documents:

1. Photographs & deterioration
2. Digitisation & restoration
3. Image modification
4. Image reconstruction
   
   (Followed by a series of documents dealing with the cleaning of all forms of photographic prints)

If you were hoping to find information outlining the procedures and costs involved in saving and restoring your old photographs... please proceed to 'Doing it!'.

 

Services & Tariffs

 

Types of photographic Paper

 

Photographic print construction

Black & White

The print is made up of three or four layers - paper plus two or three layers of gelatin.

Gelatin or gelatine is a translucent, colorless, brittle, flavourless food derived from collagen obtained from various animal by-products.

1. Paper
   Pre 1920 made of cotton, then replaced by wood-pulp - base layer.
2. Gelatin + barium sulphate
   Effectively an undercoat, sealing the paper, providing excellent adhesion for the next layer - Baryta layer.
3. Gelatin + silver grains (halides)
   It is the silver halides that react to light, to create the image - emulsion layer.
4. Hardened gelatin
   To protect the layer carrying the image - supercoat layer.

Colour

Colour photographic paper is similar, but with three emulsion layers incorporating the three base colour dyes, that together creates the colour spectrum

polyethylene coated paper was introduced, but primarily associated with colour prints, as by this time, colour photography had become the standard format.

 

Photograph deterioration

All silver based photographic materials are subject to deterioration. The silver particles that comprise the image are susceptible to oxidation, leading to yellowing and fading of the image. Poor processing can also result in various forms of image degradation.

Different print developers will have done a better, or worse job, with fresh, or old chemicals - meaning that some prints may be subject to greater deterioration.

Age of the print is key, in all circumstances.
A sharp image with good contrast, from the 20's, now looks washed out, and lacking detail.

Colour prints from the 60's to 80's are subject to high levels of deterioration, as this was new technology. In fact, black & white photos from the 50's might hold their image better - but colour was the way forward.

Post 80's high quality cameras became the norm, and with them came improvements to colour development.
The prints are still degrading, but it is less evident in comparison to the early colour photographs (and they are simply 'younger').
Examine your colour prints from the 80's and you will see that they no longer have the sharp focus that your wonderful new SLR camera provided.
Perhaps it's worth remembering that these prints were developed over 30 years ago... their life span is limited.

Note: Photographic prints can suffer severely from prolonged exposure to water (eg. Flooding).
From the above description of a photo print, you can easily imagine the gelatin layers dissolving in water... and the emulsion being exposed to dirt and chemicals.
The image can simply peel away from the paper (as can be seen in Part 4. Image Reconstruction).

 

The Solution

Digitisation is the only solution
Regardless of whether you see your collection as personal memories, or as a family record to be enjoyed by family, friends, and future generations... the only solution is digitisation.

 

 

Part 2. Digitisation & Restoration

 

Services & Tariffs