Quality Control Practices for Archival Microfilm Production

This guide lists routine quality control practices for each area of a microfilm lab so that the images produced are always reliable and meet archival standards.

Highlights

• Process control three times a day with at least three control strips
• Daily check of chemical specific gravity and Scratch Test on processors
• Monthly replacement of water and chemical filters
• Daily cleaning with a lint-free, slightly damp cloth in all areas
• Periodic resolution, density and safelight tests

Processing

Practice	Frequency	Notes
Process control strips and record densities on form A-1630	3 times a day	At least 3 control strips each time
Methylene Blue test (residual thiosulfate analysis)	1 to 3 times a day	Keep test equipment outside the processing room
Measure solution temperatures with a hand thermometer suitable for chemicals	3 times a day	Do not rely on the processor temperature display
Check developer and fixer specific gravity	Daily	Developer @ 1:7 = 1.045 to 1.055; Fixer @ 1:3 = 1.080 to 1.105
Scratch Test on each processor	Daily	If scratching persists, also test cameras and duplicators
Quality Monitoring, Methylene Blue and Fixer tests under the INFOGUARD program	Monthly	Send to the Quality Assurance Lab
Replace chemical and water filters	Monthly	Water filter 5 microns, chemical filter 30 microns

Darkroom

• Clean the film loading area daily with a lint-free, slightly damp cloth to remove dirt and static
• Monthly safelight filter test: Camera Neg films with KODAK 3, Silver Dupe films with KODAK 1, 2 or OA, and COM films with KODAK 1 or 2

Inspection and lab area

• Clean the film inspection area daily
• Check or calibrate the densitometer monthly with the manufacturer's calibration strip

Filming

• Vacuum inside and outside microfilm equipment daily
• Hold film horizontally (flange up) when loading in subdued room light to reduce edge fog
• Daily resolution and density tests on all equipment

Duplication

• Clean the duplicator film transport path daily
• Avoid leaving unused film in room light for long periods to prevent density changes
• Daily resolution and density tests, and checks of platen and cylinder cleanliness and film slippage
• Print test daily for production and quarterly for monitored film testing
• Monthly safelight test for Silver Duplicators

Raw stock storage

• Camera film: 70°F (21°C) and 50% relative humidity
• Duplicating film: 55°F (13°C) and 50% relative humidity
• Rotate stock on a FIFO basis to keep film fresh