Tape Substrate. Video: Iden1fica1on & Risk Assessment. Physical examina1on of carriers. Physical Proper1es of Tape

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1 Video: Iden1fica1on & Risk Assessment Video: Iden1fica1on & Risk Assessment Howard Besser NYU Moving Image Archiving & Preserva1on Program hhp://besser.nyu.edu/howard hhp:// Physical examina1on of carriers Physical Proper1es of Tape Handling Tapes Tape Storage For both Tape & Film Macro Environment SeXng Priori1es 1 2 Physical examina1on of carriers Physical Proper1es of Tape 3 4 Structure of Tape Van Bogart Tape Substrate Binder--Functions as a carrier for the recording material & Bonds it to the substrate Substrate--Base material on which the recording material is coated (eg. an aluminum platter or a thin ribbon of polyester film) Early tape used cellulose acetate Moisture/hydrolysis Vinegar syndrome More recent tapes are polyester terephthalate (PET) or polyethylene napthalate (PEN) Chemically stable Resist hydrolysis and oxida1on 5 6 1

2 Magnetic Particles Store recorded information Change in magnetic properties can result in loss Magnetic remanence - ability to retain a magnetic field Coercivity - ability to resist demagnetization Magnetic deterioration of the metal particulate and chromium dioxide materials Binder Layer Holds the magne1c par1cles to the base Where the problems are likely to occur binder base adhesion oxide shedding dropoff hydrolysis s1cky shed magne1c head clog Tape baking as one solu1on 7 8 Video Cleaning Machine Longitudinal Recording Van Bogart Helical Scan Recording Van Bogart Handling Tape

3 Tape Pack Problems Van Bogart Tape Pack Problems 14 Packing problems can lead to playback problems Tracks for helical scan can be skewed Tape Storage Storing Tapes Tapes should be stored fully wound in one direc1on or the other Store tapes upright (like a book) Do not store near poten1al magne1c fields Storage cases should be opaque and kept away from source of light and humidity Do not store tapes in plas1c bags Exercise the tape every few years Temperature & Humidity for Tape Storage Variance of less than 2ºC and 5% RH per 24 hours Ideally 8ºC and 25% RH Other op1ons 20 C (68 F) and 20 30% RH 15 C (59 F) and 20 40% RH 10 C (50 F) and 20 50% RH Never store below 8ºC amianet.org 2003, & ISO

4 VidiPax Video Preserva1on (Internship) For Both Film & Tape Macro environment SeXng Priori1es Monitor Temp/Humidity Thermohygrograph Hampton Collec1on (atmosphere cntrl) Academy Atmosphere

5 Macro Environment IPI Storage Guide for Acetate Film Importance of temperature & humidity control Monitoring the environment dataloggers Climas less expensive solu1ons Controlling the environment Conserva1on survey assessments, periodic monitoring of items in the collec1on Decision making on priori1es and treatments IPI Preserva1on Index temperature/humidity, Years un1l no1ceable deteriora1on Academy vault staging % RH Tempera ture Cº 2º 7º 13º 18º 24º 29º 35º Improving storage outside the Can Jean-Louis Bigourdan, AMIA 1998 lowering temperature and/or rela1ve humidity can help reduce the rate of acidifica1on in degrading film trying to remove acid within the can does not outweigh the benefits of low temperature and humidity the greatest improvements in chemical stability can be achieved with cold temperatures SeXng priori1es

6 NYU University Archives Internship Project Acid Detec1on results/autocataly1c point readings University Archives Collections University Archives (in total) Total # of items % of % of % 75 19% Audio Visual % 25 23% Brademas Papers % 0 0% Classics Dept. Tapes % 1 1% SeXng Collec1on Priori1es You collec1on will always need more 1me than you can give Triage sexng priori1es Dept. of Athletics % 10 71% External Affairs % 0 0% Abby Weed Grey % 0 0% Alice V. Keliher % 0 0% Miscellaneous Films % 39 87% Annette Weiner % 0 0% Methodology for SeXng Priori1es (1/3) Iden1fy different groupings within your collec1on By sub collec1on By age By where they ve been stored By video format Methodology for SeXng Priori1es (2/3) Survey a Random Sample in each grouping Physically inspect each of the random samples, looking for metal oxide, tape packing problems, breakage, edge damage, stretching, curling, housing damage, or other signs of deteriora1on [play each tape] Methodology for SeXng Priori1es (3/3) Analyse the data you gathered Extrapolate from your sample to project how many total tapes in each category are likely to have each problem Combine this data with other informa1on (rela1ve value of each sub collec1on, replace ability of par1cular groups of tapes, how unique certain groups are, issues with reformaxng, special funding available for certain sub groups Set priori1es based on the above Collec1on Assessment Tools New York University Visual and Playback Inspec1on Ra1ngs System (ViPIRS): Tool for Evalua1ng Audiovisual Magne1c Media hhp://library.nyu.edu/preserva1on/movingimage/ vipirshome.html Columbia University Libraries: Audio/Moving Image Survey Database hhps://www1.columbia.edu/sec/cu/libraries/bts/ preserva1on/projects.html

7 Film & Video: Iden1fica1on & Risk Assessment Howard Besser NYU Moving Image Archiving & Preserva1on Program h#p:// hhp://besser.tsoa.nyu.edu/howard/talks/ hhp:// resources.html hhp:// hhp://sunsite.berkeley.edu/longevity/ hhp:// hhp:// hhp:// web.org/tc04/ hhp:// hhp:// 37 7