Issue 4. November 1996 INTERNET EDITION

CPC Newsletter is published once a year.
Reproduction and/or translation of the contents is permitted, with acknowledgement of the source.

News and comments from The Centre for Photographic Conservation

News in Brief

1996 has been another busy year at The Centre with a new triple skinned polycarbonate roof, incorporating ultra violet screening. This caused the inevitable disruption and delays that this type of work always creates but the finished results have improved the facilities and the aesthetic appearance of the studio immensely.

The Moor's were involved with the Photographic Materials Conservation Group Open Meeting in March at the Museums and Galleries Commission in London, a brief report of the meeting can be found later in this Newsletter. The Centre's courses, including two new short courses, were held from April through to May this year; these attracted students from America and Germany as well as the United Kingdom. Though not part of the programme, but becoming a bit of a tradition during the courses, Ian and Angela were able to accompany students to the Bermondsey antique market, this means a very early morning start, 5.00am, but always results in interesting finds and puts a whole new light on the word "souvenir".

Two weeks teaching at IFROA in Paris rounded off the Summer for the Moor's but not their travelling for 1996, in November they return to China.

For the last five years The Centre has been systematically working on a notable glass plate negative collection. The quality of this collection, coupled with some enquiries and cries for help we have received, has prompted us to discuss in this Newsletter the 'fors and against' of such collections.

Personal Remembrance

It was with real sadness that we heard of the death of Dr. Klaus Hendricks on May 27th after a valiant fight for life against cancer.

  Klaus was educated in West Germany and Austria but it was in Canada at the University of Alberta that he received, in 1971, his Doctorate in Organic Chemistry. In 1975 he was appointed Photographic Conservation Chemist at the Public Archives of Canada Technical Division and was ultimately to become Director of the Picture Conservation Division at the National Archives of Canada responsible for the conservation of objects, paintings, works of art on paper, and photographs. In 1991 he became the Founder Director of the Conservation Research Division and in 1994 when it was transferred to the Canadian Conservation Institute became its Senior Research Scientist in Conservation Research Services.

We can not claim an intimate friendship with this exceptional man but with nearly twenty years of correspondence and occasional meetings, at conferences and meetings in far flung corners of the world, we built up a relationship based upon mutual respect. Klaus visited our studio in 1985.

The above picture shows Klaus Hendricks with Roy Flukinger at the AIC/PMG Winter Meeting at the Harry Ransom Humanities Research Centre, Austin, Texas, February 1993.

Our last meeting was in the Netherlands where we had the privilege of working closely with him on the "Delta Plan" Ref.1. along with Debbie (Hess Norris), Connie (McCabe) and Doug (Munson).

Our most endearing memory of Klaus is of when we had the privilege of visiting him and Genevieve, his wife, at their farm in Ontario. After a wonderful meal, and enjoying a mellowness that only fine wine and good company can bring, Klaus, Ian, Jim (Reilly) and Doug (Nishimura) went out into the Canadian snow, at dead of night. The expedition was to see Klaus' "sugar shack" deep, or so it seemed, into the maple forest where he indulged one of his other passions the collection and production of maple syrup, "liquid gold". Genevieve and I wisely stayed behind to keep warm by a blazing log fire. Ian and I returned to England carrying a bottle of this uniquely Canadian desert with Klaus' own label on it.

We would like to take this opportunity to express our sympathy to his wife, Genevieve, and also to his many friends and colleagues both in America and Europe. Klaus will be greatly missed but his legacy of research and publications will keep his memory alive in our profession.

"The great glass plate tragedy"

"We shudder to think of the thousands of vile "negatives" boxed up at this moment in holes and corners, any one of which may on a sunny day, hatch a brood of hateful "positives." We feel it is a solemn duty to remind photographers of the responsibility which they incur by harbouring these dangerous reproductive productions; and we beg of them - for their own sakes and that of society - to lose no time in washing off, or otherwise destroying, by far the greater part of these "negative" possessions." Francis Frith, 1859 Ref.1.

We are happy to say that Mr. Frith did not take his own advice and the vast majority of his own negatives still survive. There have been, however, since Frith's day many instances where historic negatives have ended their days in windows, the local rubbish dump or even greenhouses as was the tragic case of Julia Margaret Cameron whose negatives were stripped to provide the glass for a green house at Freshwater.

In these enlightened times one can not imagine that this sort of vandalism could continue, for it needs little imagination to realise that within historic negatives is a huge treasure trove of social, historical and cultural information Fig. 1 & 2. Regretfully, in many instances this treasure has yet to be discovered and explored by serious researchers on the one hand and by that stirring giant the general public on the other. One only has to peruse the popular press, magazines, film and television to see the growing use of historic images to enhance and illustrate their publications or productions whether it is the story line, advertising or even the credits; these can not fail to increase public awareness.

Fig. 1. Fashion trends tended to be set from the capital or other major cities which could produce a time-lapse before other parts of the country caught up. Except in the wealthiest of families fashions changed more slowly the lower down the social scale people were. The hair style, centre parting and plaits or loops tied at the nape of the neck and the Mandarin sleeves of this ladies watered silk dress clearly pin-points this image to the late 1850s early 1860s. As the decade progressed the Chignon became larger, more elaborate and was placed higher on the head. The sleeves by 1884 were to become more shaped to the arm. Albumen print, Photographer Camille Silvy. Moor Private Collection.

Fig. 2 The hat rather than a bonnet that this lady wears, the hair style and the Norwich Shawl, geometrical patterns or stripes woven in silk on a Cashmere ground, place the image in the early to mid 1860's. Albumen print, Photographer Mc Lean and Co London. Moor Private Collection.

Day of his triumph

It was not until after the second world war, prior to 1945 for those of you too young to remember, that photographers began to concentrate on portraits, weddings and babies, prior to this local commercial and amateur photographers would chronicle the events and changes that occurred in their area be it May Day celebrations, Beating the Bounds or Wakes Week, often feeding this rich source of local knowledge to the local and often not so local press. With few exceptions these local stalwarts would meticulously record dates, names and places with their negatives usually on the wrapper as well as in their written records. Thus, the family of Charles Marwood from Aldbrough who won the ploughing match four years in a row, or, the present owners of The Oaks at Dalston in Cumbria might find with a little ingenuity a picture of Charles along with his plough and horses on the day of his triumph, or, a record of the house before the modernisation which took place in the 1940's. Along with the local interest captured within these two negatives is the now historic information like the type of plough used and the historic building dating back to the 16th century. It was never envisioned at the time these negatives were produced that they would be of considerable interest to the Agricultural Museums, or, The Royal Commission on Historical Monuments of England, and indeed Scotland, Wales and Ireland, which was set up to gather information and particularly photographs of buildings, past, present and future, in our rapidly changing world The RCHME has some 3 million historic buildings records and photographs. Their earliest photographs date back to the 1840's; as old as photography and the RCHME itself.

We can not deny that within most glass negative collections there will be a percentage of images which never will be of any interest to anyone either now or in another hundred years. However, it would be a very brave soul who would be prepared to weed them out, even though they would have probably been gathered to their maker before they were found out, should they be wrong. God has made the mind of man so richly diverse that even from day to day it is impossible to predict what will be of burning interest to someone never mind from century to century.

"Who would have ever thought there would be a resurgence of interest
in tent spike design?"
Over the years Ian and I have been privileged to survey, undertake and supervise the conservation of many glass plate negative collections including for example the Astronomical plates at Royal Greenwich Observatory, Herstmonceux Castle in 1983. Our work allows us to explore, sometimes only by sampling but often more thoroughly, the potential of images within undocumented negative collections. We are always astonished at the quality of the photography that we find, particularly within glass negative collections, and also the wealth of information which lies in wait for future research. The earliest collodion glass plate negatives, a process invented by Frederick Scott Archer in 1851, will undoubtedly contain visual information representative of the previous fifty, if not more, years, despite the great social changes thrown up by the agricultural and industrial revolutions. Regional variations show up clearly and often the random information that is captured within images is a truer representation of the prevailing social conditions, and cultural and artistic taste at that period, than the main subject.

Forgotten Heroes

With few exceptions these collections have always been stored in less than ideal conditions and yet they have survived. For the great part they have survived despite their fragility and sensitivity because over the years those with the responsibility for their care deemed them important enough to keep, even though they had no resources to research their hidden depths or undertake even the most basic of preservation measures. We have now, and will in the future, a lot to thank these long forgotten heroes for.

More recently, policy decisions in institutional historic collections are being dictated by economic and management forces but this restructuring must be linked to the growing realisation that our heritage is also related to other issues such as development, tourism and cultural awareness. There is a very real risk that where photographic collections, and particularly negative collections, are an unplumbed resource, tragic mistakes may occur which can never be reversed. Whilst there are undoubtedly advantages to be reaped from good professional management, and one only has to observe the growth in heritage marketing for instance, it would be tragic to starve the goose that lays the golden eggs for if there are no more golden eggs there is nothing left to manage.

Fig.4. This portable dark room typical of those used by photographers employing the wet collodion process enabled them to coat, sensitise, expose and develop their negatives when working away from the studio. It was essential to keep the plate wet at all stages of the production process.

There are of course disadvantages to retaining negative collections, particularly glass plate negatives; with their material fragility, chemical sensitivity to atmospheric and material pollutants, their bulk and compound weight. Given these disadvantages one might be tempted to copy the negatives onto a more manageable and user friendly medium and then discard the original, but if we examine this concept more closely we may find that we will inherit an even greater problem.

The information content of a negative is irreplaceable, it cannot be adequately or fully conveyed in any other form, by data capture, textual, printing, drawing or painting. The degree of reality captured in a silver based photographic image has no equal. To the photographer the production of the negative was always of paramount importance.

More creative energy and manipulative skill was bestowed upon the production of a good, optimum negative than in the ensuing print, a poor negative always produced a poor print. A good negative, that is an "optimum" negative having a full density range balanced to the response of the printing paper, was essential if the image captured by the photographer was to bear fruit in the form of a "perfect" print.

In the early days of wet-collodion photography the immediacy of the process enabled the photographer to see at once the relational response between exposure and development, the two factors that determine the density range, that is the "characteristic curve", of the material. Adjustments would be made on the spot by arresting development or reducing the silver content of the developer for an over exposed negative, or, by intensification, adding silver to the developer for an underexposed negative inorder to produce an "optimum" negative. Failing these measures the subject would be reshot straight away with the necessary adjustment to exposure Fig. 4.

"Characteristic curve"

A "characteristic curve" is a graph showing the relationship between the density range of a particular photographic material, measured with a transmission or reflectance densitometer for a negative or print respectively, plotted on its vertical axis and the exposure values plotted on the horizontal axis. Both the densities and their corresponding exposure values are plotted using logarithmically numbered scales because there is a mathematical relationship between them Fig. 5.

There is a unique marriage that exists between a particular negative process and its corresponding contemporary printing paper. The particular look of a "classic" English landscape from the 1860's early 70's is more to do with the response, sensitivity and density values of the negative system and its corresponding printing paper than any current interpretation based upon aesthetics.

The development of intensification and reduction techniques provided techniques that were specifically produced to control and/or produce "optimum" negative characteristics where exposure and development alone had failed to produce them.

If the subsequent print was unsatisfactory, or, it developed a fault, the photographer could always make another one.

Francis Frith appealed against the preservation of bad, unartistic negatives and called for photographers to destroy them! Of course a photographer may destroy his own work but it is not acceptable for future generations to do so.

In an age of technological advances one might be easily drawn into the notion that the information content can be easily captured in an alternative form such as a copy negative or digital file that is more versatile in application and use than say a fragile glass negative.


Photographic duplication as a preservation tool

The provision of copy material within Photographic Archives is becoming more and more widespread as a crucial focus of an interactive Preservation Policy.

The duplication of historical glass plate negatives for information preservation and retrieval purposes is not without its technical problems some of which are not immediately obvious.

Historical negatives and prints and contemporary negative and print materials are not compatible they have different density ranges and therefore "characteristic curves". You cannot on a simplistic level, using standard photographic copying and printing techniques, copy, or print from an historical negative, onto contemporary negative or print materials, and expect to faithfully reproduce all its original visual characteristics and information content.


PCLEAR=ALL In the many Surveys that we have undertaken over the last twenty years the quality of the duplicate and copy material encountered has generally ranged from poor to adequate but rarely excellent. The underlying reason for this is the lack of an understanding of the printing characteristics of historic negatives and papers. The printing characteristics of contemporary negatives and papers are not only visually and materially completely different to historical systems but they are also incompatible and not directly interchangeable with respect to their "characteristic curves". Therefore, to extract the maximum from the density ranges of these materials, historic and contemporary, as determined by their differing "characteristic curves", a considerable degree of skill and knowledge of photographic technology is required to be able to manipulate the materials and their respective density ranges, by augmenting the factors of exposure and development.

Fig. 5The "characteristic curve" for any given photographic process is a readable, mathematical representation of the relationship between the exposure and development density values.

High quality copy material is not only essential as a meaningful resource for historians and picture researchers, and as an ongoing feature of an active Preservation Policy, it also has considerable commercial applications which if developed properly can be a valuable source of income and will do much to promote the collections.

Data capture as a preservation tool

The use of digital technology in the field of image/information preservation. manipulation and pseudo-restoration has impacted all of us who seek to preserve our cultural heritage.

Digital files can be written onto CD-Rom, video disk, magnetic tape, hard disk or diskette. To be output to a monitor, thermal or full 64 bit colour printer, silver based print, negative or transparency via a tricolour, pulsed laser printer or high quality colour printing. However:

Digital files are more prone to corruption and loss than a silver based photographic image.

Obsolescence in both hardware and software in what is a rapidly developing technological field. Unfortunately, built in obsolescence is a market force and characteristic that is controlled by the major players in the market to their advantage not the end user.

Inherent instability in the data support or carrier materials e.g. CD-Rom and Photo CD discs, magnetic tape or disc and video disc etc. Current life expectancy for a CD-Rom can be as little as three years. Ref.3.

Therefore information, although versatile in its application, exists in a form inherently more unstable than the original artefact. Although masters can be kept, they are equally prone to corruption and regeneration of copies or masters incurs a loss of data information and high cost.

The issue of surrogate or replacement information sources as part of an overall Preservation Policy for collections is invariably one of Cost v Quality, it is a sliding scale utilising for most end users Lossless v's Lossy technology.

Lossless = High Cost in image capture/scanner systems, hardware, producing large data files/memory - high resolution used at present only at the top end of the electronic printing industry and in projects such as Vasari Ref.4 Lossless compression data files can be restored to the state of the uncompressed original.

It should be stressed that even at the top end of digital technology there is as yet no scanner or other image capture device that can match the resolution potential of a good black and white negative.

Lossy = Low Cost in image capture/scanner systems, compression software reduces the data by establishing flags/data reference points within the image which enables the basic image to be reconstructed at a lower resolution in a smaller manageable data file/memory at PC user level with a resulting loss of information. The Lossy compressed data file can not be restored to the state of the uncompressed original.

Of course these photographic or digital, systems do have a vital part to play in the preservation of original material, but, they can never seriously be considered as a replacement for the original.

All artefacts created by man throughout his development have a cultural and socio-historic importance and constitute our cultural heritage. They are an expression of being, an individual and yet corporate statement of man's existence, a record of his thoughts, aspirations, needs, desires and achievements at any given point along the road that is his cultural, socio and philosophical evolution.

To understand the past is to give meaning and substance to the present and to provide a foundation upon which to build for the future.

In this context all artefacts are an important piece of a larger more complex picture, that is constantly developing, and therefore worthy of preservation.

Of course all artefacts, that is the total some of man's output, have not been and cannot be preserved. However, any loss, particularly in the hands of those charged with the preservation of our cultural heritage, should not occur on the grounds of political or economic expediency, personal taste, whim or current fashion.

1.Hans Christiaan de Herder; Going Upstream: A Travel Against World Politics. The Imperfect Image: Photographs Their Past, Present and Future. ISBN 0-9521393-0-8
2. We are unaware which publication this quote originally comes from but it came from an impeccable source, Grant Romer via IFROA student Bertrand Sainte-Marthe.
3. Mhaira Handley. Digital Archive for the Future- Stability Guaranteed. PhMCG Newsletter No. 1. 1996
4. Anthony Hamber; 'A Higher Branch of the Art': Electronic Digital Imaging and the Photographic Image. The Imperfect Image: Photographs Their Past, Present and Future. ISBN 0-9521393-0-8

Institute de Formation des Restaurateurs D' Ouvres D'Art

In October Ian and Angela were in Paris teaching fourth year students at Institut de Formation des Restaurateurs D' Ouvres D'Art in their new studio at La Plaine Saint-Denis Fig. 6. The IFROA Course is headed by Anne Cartier Bresson and relocated to La Plaine Saint-Denis in January of this year. IFROA students, who undertake a rigorous entry examination before they are accepted onto the course, undertake a four year programme in photographic conservation. Bertrand Sainte-Marthe, Annabelle Simon, George Monni and Estelle Rebourt are undertaking their final projects which include the preservation of varnished photographic prints and hand coloured Japanese albumen prints. In 1994 IFROA graduate Sandra Petrillo was an intern at The Centre, Sandra presented a paper at the Edinburgh ICOM Conference in July 1996 on the work she did on albumen print panoramas which was her fourth year and degree subject. 

Photographic Materials Conservation Group Open Meeting 21st March 1996

The PhMCG held an open meeting on the 21st March 1996 at the Museum and Galleries Commission, Queen Anne's Gate, London. Carole Milner, Head of Collection Care, The Conservation Unit at the MGC gave the opening address welcoming participants and discussing the developing role of the Conservation Unit.

Veronica Perkins, Visual Materials Librarian at the Fawcett Library, and Private Conservator Christopher R. Harvey, both gave presentations on the effects of flooding on photographs from their individual perspective of curator and conservator. Ian L. Moor, spoke on The permanence and care of colour photographs, and Conservation Scientist Margaret Hey, looked at The 'vinegar syndrome' and documentation preservation-compatible? Other presentations included The INTERNET and what it has to offer to the conservation professional from Mark Vine, Conservation Resources (UK), and Robert White, Chairman of the Conservation Forum, came not only as an observer but also as an encourager to the group discussing such aspects of the conservation profession as the need for professionalism, standards, training and unity.

The meeting was very well attended. A more detailed overview of the meeting will be published in the PhMCG Newsletter Issue 2. due out in December. The next PhMCG Open will be on the 12th June 1997.

For more information about the group contact David Parker,
C/o Conservation Dept', The Public Record Office, Ruskin Avenue, Kew, Richmond, Surrey TW9 4DU.