OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success ALA June 25, 2006 OCLC Preservation Service Centers

OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success Kelly Barrall OCLC Brenda Bailey-Hainer Colorado State Library Henry Snyder California Newspaper Project ALA June 25, 2006

OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success Kelly Barrall, Manager Quality Assurance Joan DaShiell Sr. Digital Project Manager OCLC Preservation Service Centers ALA June 25, 2006

OCLC Online Computer Library Center Selecting Microfilm for a Digital Imaging Project  Microfilm Format  Film Generation  Determining Film Base & Polarity  Evaluating Technical Criteria  Microfilm To Digital – Tips For Success!

OCLC Online Computer Library Center Selecting Microfilm for a Digital Imaging Project 1 ST Step  Determine format of microfilm available

OCLC Online Computer Library Center Microfilm Format Determination 35 mm  Preservation microfilm  Larger frames/smaller reduction  Negative or positive  Acetate ?  Diazo/Vesicular  16mm/105mm

OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success 2nd step  Determine generation of microfilm

OCLC Online Computer Library Center Microfilm Generation Determination Archival Master  Camera film  1st generation  Negative  Acetate ?

OCLC Online Computer Library Center Microfilm Generation Determination Print Master  Duplicate copy  2nd generation  Negative  Acetate ?

OCLC Online Computer Library Center Microfilm Generation Determination Service Copy  Duplicate copy  3rd generation  Positive  Heavily used  Acetate ?

OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success 3rd step  Determine base and polarity of microfilm

OCLC Online Computer Library Center Acetate or Polyester Base? What’s better for digitization? Microfilm Base Determination

OCLC Online Computer Library Center Acetate  Deteriorating  Warped  Brittle  Curled Microfilm Base Determination  Dirty  Scratched  Unstable  Easy to tear

OCLC Online Computer Library Center Steps to determine if your film is acetate Hold a wound reel of film up to the light: If opaque (light will not pass through it) the film is most likely acetate Unwind several inches of film: acetate film tends to curl across the width of the film Acetic Acid is vinegar. Acetate film that is deteriorating most likely will have a vinegar odor present. VIEWCURLSMELL

OCLC Online Computer Library Center Polyester  Preservation  Stable  Durable Microfilm Base Determination

OCLC Online Computer Library Center Negative or Positive Polarity? What’s better for digitization? Microfilm Polarity Determination

OCLC Online Computer Library Center Positive  Usually 3rd generation  Lower resolution  More scratched Microfilm Format Determination

OCLC Online Computer Library Center Line that separates columns Heavy scratches Example: Heavily scratched positive microfilm

OCLC Online Computer Library Center Negative  Usually less noise  Better contrast for text and optical character recognition (OCR) Microfilm Format Determination

OCLC Online Computer Library Center Example: digitized from negative microfilm

OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success 4th step  Evaluate technical criteria

OCLC Online Computer Library Center Microfilm Technical criteria Reduction ratio  Newspapers filmed at 20:1 or lower are optimal  Newspapers filmed at a higher resolution could contain small text that is not legible

OCLC Online Computer Library Center Microfilm Technical Criteria Resolution  Focus achieved at the time of capture, measured with a 100X microscope  Poor resolution = fuzzy text = poor OCR

OCLC Online Computer Library Center Microfilm Technical Criteria Density Range  Film created to meet preservation guidelines  Film too light or too dark = poor OCR  Film with uneven lighting = poor OCR

OCLC Online Computer Library Center Example: Uneven lighting – lost text Lost text

OCLC Online Computer Library Center Review Steps  Microfilm Format— 35mm  Microfilm Generation— archival, print master, service copy  Microfilm Base & Polarity— acetate vs. polyester; negative vs. positive  Microfilm Technical Criteria— reduction, resolution & density

OCLC Online Computer Library Center Tips for a successful microfilm to digital project Know your microfilm  Quantity  Quality  Contents

OCLC Online Computer Library Center Tips for a successful microfilm to digital project Quantity  Frame count = 1up/2up  Targets  ISE intentional second exposures  Duplicates

OCLC Online Computer Library Center Tips for a successful microfilm to digital project Quality  Poor original  Poor filming  Poor condition of the film

OCLC Online Computer Library Center Tips for a successful microfilm to digital project Contents  Newspaper format  Size of the paper, including supplements and full page spreads  Was it filmed bound?  Title changes, should it be treated as one?

OCLC Online Computer Library Center Review tips for success!  Quantity – how many images do you really have  Quality – poor quality film = poor quality images  Contents – bound newspapers and title changes

OCLC Online Computer Library Center Microfilmed Newspapers: Selection for Digitization Success Microfilm to digital

OCLC Online Computer Library Center Digitization and imaging options  Duplicate to polyester  Image enhancement  Dynamic threshold adjustment

OCLC Online Computer Library Center Questions? Kelly Barrall/Joan DaShiell