Monday, September 8, 2008

The Longevity Of Photographic Prints In Relation To Record And Survey Work.

A recent dictum of the Camera Club indirectly revives the question of the permanence of different printing processes to be used as records by photographic survey and record societies. Perhaps the most widely understood meaning of the word "permanent," applied to everyday things, appertains to inalterability, but in photographic circles when questions arise as to tine relative permanence of different printing processes their respective "durability" is generally meant and as so understood. Degrees of (.inalterability is rather a contradiction in terms, whilst durability may widely vary. To put the matter bluntly, if any printing process will afford lasting results for, say, a dozen, or so years and upwards, it is generally considered to be permanent in the restricted sense alluded to. But the matter is on another footing when, photographs are to serve as records for posterity, for here it is not enough that they should last for fifty or even a hundred years, but a life is reasonably demanded limited only by the holding together of the picture supports. By general consensus of opinion, two commercial printing processes only, or variants of them, fulfill this condition. The life of silver prints at the best is one of conjecture, which the lapse of time only can settle, and many are known to be more or less evanescent. In the case of photographs utilized purely as records their useful existence is longer than for most other purposes: if discolored or partially faded, so long as all details are preserved, they serve their purpose. On the other hand, when once deterioration has begun it often proceeds apace.
Though all are agreed that complete fixation and thorough washing are essential elements in the stability of silver prints, yet it cannot be said that deterioration can only be ascribed to these operations being ecamped, and there may be operative causes which are quite unsuspected. Printers of the old albumenized paper have narrated how prints known to be hurriedly fixed and washed have sometimes long outlasted those which had received orthodox treatment. In past days albumenized prints appear to have been over-washed, as in addition to prolonged changes by hand they were frequently left to soak all night. Impure air, damp, impurities in the mount or mountant, or a mountant tending to turn acid or are all known factors tending to alteration and fading Even with one brand of paper puzzling differences he durability of prints arise, one worker recording rapid fading, or other troubles, whilst another experiences he opposite. Inquiries often fail to reveal any variation in procedure to account for such difference, which in some irrational way seems to be connected with the ''personal equation" which looms largely in other directions.
In daylight silver-printing processes the image may be to consist of something in the nature of a stain, whilst with bromide prints we have reduced silver in a fine state of division in gelatine, and the general opinion is that them are the most stable of all silver prints. The life of a dry-plate bears on the permanency of bromide prints, though we should expect the former to outlast the latter owing to the silver and gelatine being present in greater degree, and also to the fact that there is no paper to retain residual traces of hypo. Comparatively few old dry-plate negatives show unimpaired condition, but at Greenwich Royal Observatory there is no indication of fading in any dry-plate negatives of stars, although many date back more than twenty years. Doubtless scrupulous care was exercised in fixing and washing and none have been indemnified or even reduced.
Whilst nobody can place a limit on the life of a carefully made bromide print, which may last many a long year, yet the official pronouncement of the Camera Club that "a well-made, thoroughly fixed and washed bromide print is probably as permanent as a print in any other process" cannot be justified. The probabilities are against this conclusion, and at variance with the opinion of recognized authorities, and with the views of the great majority of photographers. In essence, the assertion is equivalent to saying that finely divided silver, vulnerable to many adverse influences, is as stable a substance as, say, lamp- black, or platinum black, both regarded as unalterable trader every atmospheric condition, and respectively employed in the carbon and platinum processes. Having regard to the support and to the fact that the platinum image is in actual contact with the fibred of the paper, mercenarily of the highest grade, a platinum print may present an advantage over % carbon when a long-distant future is concerned, but both can fairly be bracketed together as truly permanent photographic printing images. Neither, of course, exists commercially on the strength of feature, but on the distinctive qualities associated with them. The extraordinary resisting properties of platino- type prints were illustrated some yean ago, when a number remained at the bottom of the sea for some months in a sunken warship and were eventually salved none the worse for the adventure. Subsequently shown at the Brussels
Exhibition, they perished by fire. Although the image of a carbon print is not in contact with the fibred of the paper, the pigment it locked in insoluble gelatine, known to be most durable in Ha normal state, and presumably more so when tanned by the action of light. As to the danger of peeling, sometimes alleged to exist, all that can be is that this is of the rarest occurrence, and when it does take place may usually be traced to the under-soaking of the transfer paper, or over-hardening of the prints by chrome alum or similar chemical, or to undue baste in drying Preference, naturally, will be given to those tissues which contain carbon pigment, however durable other pigments utilized may be.
If the opinion of those responsible for the recent utterance of the Camera Club is based on the undoubted fact that many bromide prints made years ago show not the slightest signs of alteration, this proves that the prints are long-lived, but affords no information as to their ultimate life. We have in our possession a framed salver print (apparently albumen) of French origin purchased over sixty years ago, made long prior to the introduction of bromide papers, and only during the last few years has it shown signs of deterioration, though continuously exposed to daylight, and occasionally hung on walls none too dry. Possibly in another twenty years or less the picture may have disappeared.
Granted that carbons and platinotypes are the processes for record work, which nearly all secretaries of photographic record societies fully recognize, yet the unfortunate fact remains that if these were insisted upon few prints would be received, as the majority of amateurs print in neither process. So such societies are practically forced to accept silver prints, and with no guarantee even that they have been thoroughly fixed and washed. Possibly a dry silver print hermetically sealed and kept in the dark might last almost indefinitely, but this is outside the region of practicability. However stored for access, it is impossible to prevent a limited circulation of air and of any impurities in it over the prints owing to barometrical changes. Dry-mounting on pure paper, and a coat of good varnish applied to the surface, should materially help towards longevity. In the case of subjects obviously valuable as records, the loan of the negatives might be sought to enable permanent prints to be obtained, but unfortunately funds are often not available for the purpose. We feel sure carbon or platino type printing concerns would charge on the lowest possible basis, and on inquiry have received from two well-known firms an unofficial intimation to this effect.
There appears to be no specific authority conferred on any local authority to enable a small grant to be made for such a worthy object. But when the record society becomes part of the public free libraries (as in most cases should be the case for convenient reference) the general powers of expenditure are available. These are by no means great under the existing rate, which leaves but little margin for the purchase of necessary books, to say nothing of other desirable acquisitions. Many towns, however, have proposed an advance in the rate to 3d, and if than materializes prospects will be brighter for the societies associated with the libraries, if not for the ratepayer.
We wish all good-luck to the scheme of the Camera Club, and commend our observations to its attention, and in doing so a gentle reminder may be given to readers every where not to forget their local survey and record in the approaching season. Upon the executive, as a rule, falls the major part of the work, cheerfully undertaken and with no hope of being personally thanked by posterity, but we would urge a large measure of contribution by the general body of photographers.

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