Test 4 Unit 5 Flashcards
Basic rules of film processing
standardize procedures
keep clean and well maintained
location
adjacent to exposure room
radiation protection
ensure no exposure to the darkroom
size
6’x8’
environment
tight light
work area
dry and wet areas. Formica tabletop.
plumbing
hot and cold for mixing chemicals and cleaning processor. hardness of water can affect film
electrical
110V to operate
ventilation
should ventilate chemical vapors/odors
film storage
clean, dry, low humidity. 50-70 degrees. Stand on edge, not stacked or flat
commercial film bin
many have a security systems that prohibits bin from being opened with light on
passbox
metal lined box installed in the darkroom wall to safely pass exposed and unexposed cassettes
Chemical protection
rubber gloves, aprons, eye wash, MSDS sheets
Exam room Walls
primary 1/16” lead, 7 ft tall
secondary 1/32” to the ceiling
dark room entrances
maze, rotatrek, double door, single door
Patient ID marking system
patient ID info is flashed onto film after it has been exposed and before processing
wall color
light colors reflect light which help keep safelight intensity to a minimum
types of light needed
overhead - higher than usual
safelight - lower at regular level
safelight
red. GBX-2 filter is common for both blue and green sensitive film
exposed film is _____ x more sensitive to light of all wavelengths
10
Post Exposure Fog (PEF)
results from exposure to the film after initial X-ray exposure but before processing
Ways to reduce PEF
safelight wattage below 15W (preferred 7.5W)
4’ distance to work area, indirect lighting
use a single safelight
eliminate white leaks
Kodak Safelight Test
designed to determine the safe handling time of unexposed and exposed film under safelighting conditions. Prexpose half of 8x10.
Processing time is determined by…
developer temperature and concentration
an increase in temperature =
shorter developing time
a decrease in concentration=
shorter developing time
automatic processing
mechanized, faster, less variable, more initial expense
manual processing
hand tanks, time consuming, variable, lower start up costs
Autoprocessor components
roller transport system temperature control system chemical system replenishment system circulation/filtration system drying system electrical system
The processing cycle
Develop
Fix
Wash
Dry
transport system
1”&3” rollers that move film in and out of tanks.
entrance roller
grabs film
deep racks
move film through solutions
turnaround rollers and guide shoes
push film upward
crossover
moves film to next tank
squeegee
removes excess liquid before drying
Developer
turns latent image into manifest image. film density and contrast established here, odorless and clear with a light amber appearance. temp should be monitored on daily start up
primary wall
directly behind bucky
secondary wall
to the right or left of bucky
hydroquinone
reducing agent. slow acting agent responsible for dark tones on film. Time and temperature sensative
phenidone
reducing agent. fast acting agent responsible for gray tones on film. works on lighter areas of exposure. time and temperature sensitive
Glutaraldehyde
hardener. keeps emulsions from over-swelling
reducing agents
in developer. responsible for building film density and contrast
Fixer
- stops developing process
- removes undeveloped silver from the film
- shrinks and hardens the emulsion
acetic acid
acidifier. stops the developing process on contact
aluminum chloride
hardener. shrinks and hardens emulsion
dryer
infrared dryer operating at 120F. dries film in under minute
temperature control system
developer heater core and a thermal sensor in the developer tank, and a modular control unit.
a ____ % swing in temp is enough to double or cut film density in half
3
how long to table top processors take to stabilize developer temperatures?
15-20 minues
Never insert a _______ thermometer into the processor
mercury
recirculation
agitates developer solution. stabilizes temperature. should be between 90-95F. filters sediment
