IMAGE ACQUISITION

1
IMAGE ACQUISITION

• FILM SCREEN SYSTEM

2
PROCESSING THE LATENT IMAGE

• AUTOMATIC
• DARKROOM PROCESSOR
• DAYLIGHT PROCESSOR
• 45 SECONDS TO 3.5 MINUTE PROCESSORS
• PROCESSOR CAPACITY OF FILMS THAT CAN BE
  PROCESSED PER MINUTE
• LARGER FILM SIZES TAKE LONGER TO GO THROUGH THE
  PROCESSING CYCLE

3
FOUR STAGES OF PROCESSING

• DEVELOPER
• FIXER
• WASH
• DRY

4
DEVELOPER

• LATENT TO MANIFEST IMAGE
• AMPLIFY AMOUNT OF ATOMIC SILVER AT SENSITIVITY
  SPECK
• REDUCE THIS SILVER TO METALLIC SILVER

• METALLIC SILVER TRANSLATES TO VARIOUS
  RADIOGRAPHIC DENSITIES
• UNEXPOSED SILVER HALIDE DOES NOT REACT TO THE
  DEVELOPING CHEMICALS UNLESS

5
DEVELOPER CONT.

• THE FILM STAYS IN THE DEVELOPING CYCLE TOO LONG
• OR
• THE DEVELOPING TEMP. IS TOO HIGH
• WHAT MIGHT CAUSE A FILM TO STAY TOO LONG IN THE
  DEVELOPER?

6
DEVELOPING AGENTS

• YESYOU NEED TO KNOW AGENTS BUT YOU DO NOT NEED
  TO KNOW THE SPECIFIC CHEMICALS
• DEVELOPING OR REDUCING AGENTS
• ACCELERATOR OR ACTIVATOR
• ALKALINE
• RESTRAINER
• PRESERVATIVE
• HARDENER

7
FIXING

• PRIMARY FUNCTION?
• FIXING AGENT
• ACIDIFIER
• PRESERVATIVE
• HARDENER
• SOLVENT
• HYPORETENSION

8
THE PROCESSOR

• FEED TRAY
• ENTRANCE ROLLER ASSEMBLY
• AUDIBLE SIGNAL
• ACTIVATES REPLENISHMENT SYSTEM (CIRCULATORY
  SYSTEM)
• TRANSPORT ROLLERS
• SQUEEGIE ASSEMBLY
• TURNAROUND ROLLER
• CROSSOVER ROLLER
• GUIDE PLATES

9
MORE TERMS

• MICROSWITCH
• REPLENISHMENT
• OXIDATION
• AERIAL/USE
• FILM ORIENTATION
• TEMPERATURE
• 93 DEGREES TO 95 DEGREES
• 50 HUMIDITY-DARKROOM
• ARTIFACTS PGS 218-221

10
DIGITAL ACQUISITION

• DYNAMIC RANGE RANGE OF VISIBLE IMAGES
• MATRIX AND PIXELS
• THE LARGER THE MATRIX THE SMALLER THE PIXEL SIZE
• THE LARGER THE MATRIX THE GREATER THE NUMBER OF
  PIXELS

11
DIGITAL ACQUISTION - CR

• IMAGING PLATE IS PLACED INTO A READER
• INSIDER THE READER THE PLATE IS SCANNED BY A
  LASER WHICH RELEASES THE TRAPPED X-RAY ENERGY AS
  VISIBLE LIGHT
• THE PMT (PHOTOMULTIPLIER TUBE) COLLECTS,
  AMPLIFIES AND CONVERTS THE LIGHT INTO AN
  ELECTRICAL SIGNAL

12
DIGITAL ACQUISTION - CR

• SIGNAL IS ANALYZED TO THE PREPROGRAMMED
  INFORMATION
• ELECTRIC SIGNAL IS CONVERTED FROM ANALOG DATA TO
  DIGITAL DATA
• LASER SCANS PLATE TO ERASE THE PLATE THOROUGHLY
  FOR NEXT EXPOSURE

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DIGITAL ACQUISTION - DR

• CCD
• FLAT PANEL
• INDIRECT CONVERSION DETECTORS
• DIRECT CONVERSION DETECTORS

14
DIGITAL ACQUISTION ADDITIONAL TERMS

• HISTOGRAM
• ALGORITHMS
• POST PROCESSING
• WINDOW LEVEL
• WINDOW WIDTH
• NOISE
• DICOM
• PACS