CABARET of SPIRITS Atelier ... BLOG VERSION

CABARET of SPIRITS Atelier ... BLOG VERSION
...Photographs should be protected from extended exposure to intense light sources. Limit exhibition times, control light exposure, and monitor the condition of the photographs carefully. Prolonged or permanent display of photographs is not recommended. Use unbuffered ragboard mats, and frame photographs with archivally sound materials. Use ultraviolet-filtering plexiglass to help protect the photographs during light exposure. Reproduce vulnerable or unique images and display the duplicate image; in this way, the original photograph can be properly stored and preserved.

Disaster preparedness begins by evaluating the storage location and the potential for damage in the event of a fire, flood, or other emergency. It is important to create a disaster preparedness plan that addresses the specific needs of the collection before a disaster occurs.

The location and manner in which photographs are housed can be the first line of defense. Identify photographic materials that are at higher risk of damage or loss. Remove all potentially damaging materials such as paper clips and poor-quality enclosures. Store negatives and prints in separate locations to increase the possibility of an image surviving a catastrophe. If a disaster occurs, protect the collection from damage by covering it with plastic sheeting and/or removing it from the affected area. If using plastic, make sure not to trap in moisture as this could lead to mold growth. Evaluate the situation and document the damage that has occurred. Contact a conservator as soon as possible for assistance and advice on the recovery and repair of damaged materials.

PS .If your photograph requires special attention or you are unsure about how to protect it, you should contact a conservator.To search for a conservator near you.






Cabaret of Spirits ATELIER

Cabaret of Spirits ATELIER

Treatment Options for Photographic Materials may include

mold removal
surface cleaning
stain reduction (only if possible and safe to do so)
tape and adhesive removal
separation from poor quality mounts
consolidation of cracked or flaking emulsion
mending tears or breaks
conservation of cased photographs and case repair
daguerreotypes
ambrotypes
ferrotypes
electro-cleansing of tarnished daguerreotypes
rehousing options
four-flap enclosures
clamshell boxes
polyester sleeves
encapsulation
conservation framing

PRESERVING & PROTECTING PHOTOGRAPHS

PRESERVING & PROTECTING PHOTOGRAPHS
Hundreds of millions of photographs have been lost over the years to natural disasters, wars, and the age-old urge to clean house. So there is something special about every old photograph that's survived. Someone decided to make it... someone else, to buy it... and a lot of someones decided to keep it over the years. Whether you're the caretaker of a treasured family album or a collector who has searched out the classics of photography, it's important to preserve and protect the images you value. Fortunately, there is new information about what to do and what to avoid. And there are specialized products available to help.

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~ *~ It all starts as a photographer... the path leads me to specialized in the conservation & application of fine art and historic photographs and restoration of paper ... working in my Boudoir, CABARETøf SPIRITS ~ *~

Archive you missed the past months

Wednesday, 5 April 2017

sea/son ... the SEASON




,,, thousands of projects in many contexts,
In these Easter cleaning between books magazines and papers photographs would
deepen a technique photography much used but little known ...
" Silver gelatin DOP "









Silver gelatin DOP is based on the light sensitivity of silver halides, which are suspended in a gelatin binder on a baryta paper support. DOPs made their first appearance in the mid 1880s and became the dominate printing process of the twentieth century. Due to the complexity of the process, silver gelatin papers have always been a manufactured product. As chemists’ understanding of silver halide chemistry increased over time, papers could be manufactured with a variety of characteristics, including varying light sensitivities, speeds, and tonal ranges. Papers were also produced with a variety of surface sheens, textures, paper thickness and paper tints. Optical brightening agents were introduced to papers beginning in the 1960s, which serve to make the highlights brighter providing papers with more contrast.
"Silver gelatin DOPs have a paper support. Most prints made before 1970 have fiber-based paper supports of varying paper weights. The standard weights are described by manufacturers in different ways including: heavy, medium, and light weight; single-weight, double weight, lightweight, extra thin. Water-resistant papers coated with cellulose acetate were made before the late 1960s. These papers were used in photo booths, as ID pictures, and for printing map reproductions, among other things that required fast processing. In the late 1960s papers coated with polyethylene, called resin-coated (RC) papers, were introduced. RC papers are coated on the back with clear polyethylene and on the front, directly below the emulsion, with pigmented polyethylene and are easily identified by their smooth plastic back. Specialty metallic papers were marketed until the 1970s. These have a special surface that give the print a metallic appearance". 
Significant advancements were made throughout the twentieth century to silver gelatin emulsion making for both negative and print materials. During manufacturing of the emulsion, silver nitrate is combined with a halide (usually a combination of bromide and chloride, though silver iodide papers were also made) in the presence of gelatin with an excess of halide present. The gelatin slows the formation of the crystals allowing for smaller, more uniform crystals to form and react with impurities (sulfur) in the gelatin, all of which make the silver halide crystals more light sensitive. The emulsion is then heated in a process called Ostwald Ripening which increases silver halide sensitivity and creates more uniform silver halide crystals. The next step is to remove impurities from the gelatin. Initially emulsions were shredded into noodles, washed to remove impurities, and then heated and re-melted. Later emulsion making required a complicated procedure of flocculation which required altering the pH of the emulsion causing the silver halides to precipitate out. The silver halides were washed and dispersed back into the emulsion. Another way of extracting impurities is through reverse osmosis through a thin membrane. Finally additional sensitizing chemicals and other additives are added. Gelatin is the perfect binder for silver halide crystals; it has the ability to swell allowing the penetration of processing solutions, but is tough and resistant to abrasions when dry. The gelatin emulsion was then machine coated onto a baryta paper support.
 A final thin layer of hardened gelatin was applied to act as a protective layer called an overcoat, also called a supercoat or topcoat.
DOPs can be contact printed or printed by enlargement through a negative. During exposure, a latent image is formed where light strikes the paper. Development reduces the silver ions in the latent image to visible silver particles in an oxidation-reduction reaction. Development is followed by a stop bath, which halts development and keeps the following fixing bath from being contaminated with developing solution. Next, unexposed silver halides are removed in a fixing solution, usually sodium thiosulfate, which dissolves silver halide crystals into a water soluble compound. Finally the print is washed thoroughly to remove residual processing chemicals and by products produced during fixing.



Photographers may choose to tone prints to alter the image color and/or to increase the stability of the print. Popular toners include gold, polysulfides, and selenium or a combination of sulfide and selenium.  Gold toning replaces part of the silver image with a more noble metal (gold). Gold toning usually produces a cooler neutral image tone of blue-black. Selenium and sulfide toners create a compound with silver that is more stable than silver alone. Image tones generally range from sepia, brown, purple, and purple-brown. This can be done by indirect toning in which after fixing the silver image is bleached and then immersed in the toning solution. The sulfide solution reacts with the silver halides to form silver sulfide. Direct toning does not require bleaching. Dye toning converts the silver image to a dye mordant that attracts dye from a dye solution. Finally, metal ferricyanide toning converts the silver image into silver ferricyanide complex which is then converted to a ferricyanide salt of a different metal (iron, copper, uranium). Dye toning and metal ferricyanide toning can result in a diverse rainbow of image colors.