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Photography & NegativesAmy DelPo, Elise Blas, Kristin
Mammel, Paul Mascareñas
Photography andNegatives
Definitions of PhotographyThe science of capturing light onto a piece of film.
And…
The art of recording an image.
Oracle Education Foundation
A photograph is created when light, or another form ofradiant energy, falls on a light sensitive area such as photographic film or an electronic imager and an image is created.
School Curriculum for Photography
Definitions of a Negative
A reversed light/dark image formed on film that may be used to make prints.
Milwaukee Museum of Art
A negative is created when camera film is exposedto light. The negative is then used in the darkroomto print a photograph (positive) onto light-sensitivepaper.
Malane Newman
History of PhotographyJoseph Nicephore Niepce
Created the first permanently captured image in 1827
“View from the Window at Le Gras”
Louis Daguerre
“Boulevard du Temple”First photograph of a person
Daguerreotype
Image is exposed directly onto a mirror-polished surface of silver bearing a coating of silver halide particles deposited by iodine vapor.
Edgar Allan Poe 1848
Abraham Lincoln 1846
Daguerreotype Camera
1839French government bought rights and the photographic process became public
In the same year, Sir John Herschel first coined the term “photography”when addressingThe Royal Society of London
Created “Daguerreomania”
William Henry Fox Talbot
Created the “Calotype” circa. 1839
The calotype essentially infused paper with silver nitrate or silver chloride. This process produced a “negative” from which anunlimited number of positive prints could be made.
“The Footman” 1840
Frederick Scott Archer 1851Wet-Collodion exposureprocess and Ambrotype
The collodion process required that the coating, exposureAnd development of the image should be done while the plate was still wet.The Ambrotype process created a direct positive.
AmbrotypeWet Collodion process
Dr. Richard Maddox
1871Created dry plate process using gelatin as the basis for the photographic plate. This did away with the need for darkroom tents.
1889George Eastman introduced the box camera with the slogan “You push the button and we do the rest” thus openingthe world of photography to the masses.
1924Oskar Barnack invented the first 35 mm camera
Physical Structure
Photos are composed of three layers:
1.Support Layer2.Binder Element3.Final Image Material
Support Layer
Can be made up of:PaperResin-coated paperPlastic filmGlass
Binder Element
Usually made of gelatinBut…Could also be composed of:Albumen or collodion
(This layer holds the image-forming substanceor final image material to the support layer)
Final Image Material
This layer is made of:Color dyesSilverPigment particles
(Typically suspended in the binder or emulsion layer)
Means of IdentificationIn the past, optical microscopy has typically beenThe main tool used for identification of photos.However, there are some newer forms of photo identification:
XRF- X Ray Fluorescence
ATR-FTIR Spectrometer(Attenuated Total Reflection Fourier Transform Infrared)
ICP-MS(Inductively Coupled Plasma Mass Spectrometry)
Arrrrrggggh!
Salvaging your photos when disaster strikes
Caveat
• Always contact a conservator first.
• They have fancy methods for salvaging photos.
Flood
Floods Happen
• River overflow• Hurricanes• Tornados• Storms• Leaking pipes
• Photos must be treated within the first 24 to 72 hours (estimates vary).
• Call a conservator.• If you can’t treat, freeze.• Otherwise:
• Mold grows within 48 hours.• Photographic emulsions and binder layers may soften and
dissolve• Stacked photographs and/or photographs in albums may
permanently adhere to each other.
Step One: Act Fast
Step Two: Prioritize• Black-and-white prints are more resistant to
damage than color.• Photographic film-based negatives can survive
longer than prints.• Some photographic materials (such as salted
paper, albumen, platinum, cyanotype, and most photomechanical processes) can survive water immersion for 48 hours.
• So: Salvage prints prior to negatives and color materials prior to black-and-white.
Step Three: Deal With the Conditions
• Increase air circulation.
• Decrease humidity.
• Turn off heat.
• Open windows and doors.
• Use fans and dehumidifiers.
Step Four: Rinse and Clean
• Remove mud and debris from photos by rinsing them gently in a bath of cold water.
• Hold photos on the edge.• Change water frequently to keep it clean.• Gently pull-apart photos from each other or
from albums.• Do not try to rub dirt off.
Step Five: Dry
Two basic options:
Air drying
Vacuum freeze drying
Air Drying
• Works for small numbers of damp photos.• Most gentle and least damaging of the drying
methods.• Labor and space intensive.• The process:
• Place each photo on a clean absorbent paper, face up.
• Replace paper every hour.
• Use a fan to speed up the process.
Vacuum Freeze Drying
• Good method for large collections of negatives.• This process may actually damage photos, but
won’t affect a negative’s ability to make a photo.
• The process:• Place materials in a vacuum chamber.• Dry photos at temperatures below freezing.• This may take several weeks.• Re-humidify to prevent embrittlement.
Fire
Fire Damage Includes:
• Plastic supports and frames become deformed.• Photographic emulsion becomes embrittled.• Paper supports get stained by soot and smoke.• Plastic enclosures melt and adhere to the
photos.• Everything gets water damaged.
What to Do:
• Call a conservator.
• Put aside photos that are dry but damaged by soot. You can deal with them later.
• Follow “Flood” instructions for photos that are water damaged.
For Dry Photos
• Use a soft brush (such as a Hake brush) to brush loose debris off photos into a vacuum cleaner nozzle.
• Tip: Put gauze over the nozzle and open the vent to reduce suction.
• Pick soot off the photos by rolling a kneadable eraser across them.
PreservingNegatives & Photographs
Negatives
• Cellulose Acetate
• Cellulose Nitrate
• Glass Plate
Wyoming State Archives
Storage
• Sleeves
• Acid Free Box
• Away From Photographs
Wyoming State Archives
Handling Negatives
• White Gloves
• Support the Negative
• Minimize Exposure to Light
Photographs Storage
• Sleeves
• Archival Boxes
• Hard Anodized Metal Shelving
• Map Cases
Wyoming State Archives
Wyoming State Archives
Storing Photographs& Negatives
• Store Photographs and Negatives Separately
• Environmental Control
• Monitor Humidity and Temperature
Wyoming State Archives
Personal Collection
• Take Photographs Out of Basement
• Acid Free Boxes
• Keep Negatives Apart from Pictures
Causes of Deterioration
The Photo• Composite of several different layers
– Support– Binder– An image forming component
• Each one reacts different to the immediate environment and in some cases to each other
The Photo Cont…• The “support” of a photograph
– ceramic, glass, metal, paper, plastic, wood, or a variety of other media.
• The “binder” carries the image. – gelatin, gum Arabic, albumen, collodion, or starch.
• The image– based on organic dyes or silver-sensitive salts.
– organic dyes are susceptible to a wide range of pollutants and prone to chemical degradation.
Photo Deterioration
• A chemical reaction - off gassing
• poorly stored photos
• residual processing chemicals
• Acid migration • sulfur interacts with
silver compounds which forms silver sulfide causing the image to turn brownish yellow.
Chemical Reaction
Handling Photos• May cause scratches, tears, creases, broken
images. • Oils and chemicals from the human skin can
cause permanent damage by way of residual effects.
• Improper handling • at the corners rather than supporting the photo
underneath.
• crack the emulsion
Exposure to Light
• Ultra Violet Rays cause photos to fade. • light intensity multiplied by time.
• Displayed photos are more susceptible to damage and fading by light levels and exposure time than temperature and humidity.
Light Exposure
Inadequate Washing
Temperature & Humidity
• Temperature should not exceed 70 degrees • Increase the rate of chemical reactions
• Temperature should not fall below 60 degrees• e.g., plastic enclosures may trap moisture and
cause ferrotyping, which means “sticking resulting in shiny areas.” This is due to areas of high-humidity or in water-related disasters.
Temperature & Humidity
• Relative humidity in excess of 60 percent can cause more damage to a photo than heat.
• High relative humidity and heat are more damaging together than alone.• Mold and fungus• Decay of mounting boards
Storage• Wooden shelves, cabinets and drawers
• plywood, • pressboard, or • chipboard
• wood contains lignin, peroxide, and formic acid, which could leach out in interact with the chemicals in your photos.
• Wood also absorbs and retains moisture which causes swelling, warping, and mildew.
• Photographs stored near or around overhead steam or water pipes, or other sources of water may risk exposure to these harmful elements.
Storage damage
Other Threats
• Fire
• Flood
• Earthquakes
• Bugs
• War
• Vandalism
References
• Badger, G. (2003). Collecting Photography. London: Mitchell Beazley.
• DePew, J.N. (1991). A library, media, and archival preservation handbook. California: ABC-CLIO, Inc.
• Eaton, G. (1970). Preservation, deterioration, restoration of photographic images. In H. W. Winger & R. D. Smith (Eds.), Deterioration and preservation of library materials (pp. 85-98). Chicago: University of Chicago Press.
• Films for the Humanities and Sciences (1995). Preserving works of art. VHS, 23 minutes.
References• Interview with Roger Joyce at Wyoming State
Archive, March 7, 2008• Kodak. (1979). Preservation of Photographs.
New York: Eastman Kodak Company.• Taylor, M.A. (2001). Preserving your family
photographs: How to organize, present and restore precious family images. Cincinnati, Ohio: Betterway Book.
• Tuttle, C.A. (1995). An ounce of prevention: A guide to the care of papers and photographs. Denver: Rainbow Books, Inc.
References• http://www.naa.gov.au/services/family-
historians/looking-after/fire.aspx#section5• http://www.ccaha.org/pdf/salvage%20photos--
SMALL.pdf• http://www.loc.gov/loc/lcib/0105/
conservation_corner.html• http://www.restorationsos.com/education/water-
damage/recovering-from-water-damage/cleaning-repairing-and-disinfecting/clean-dry-repair-and-disinfect-paper/photos.asp
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