RADIOGRAPHIC FILM PROCESSING

DARKROOM

THE PROCESSING AREA

• PROCESSING AREA

• VIEWING SECTION

VIEWING AREA

PROCESSING AREA

VIEWING SECTION VIEWBOX ILLUMINATION INTENSITY-500-1000 FOOT CANDLES

PHOTOMETER IS USED TO MEASURE VIEWBOX

ILLUMINATION INTENSITY

VIEWING STATION

VIEWBOX LIGHT

IF ONE BULB IS BLOWN ALL BULBS HAVE TO REPLACED

VIWBOXES

• TO BE CLEANED ONCE EVERY 6 MONTHS

• IF USED 24/7 – BULBS CHANGES ONCE A YEAR

• IF USED 12/7 BULBS CHANGED ONCE EVERY TWO YEARS

VIEWING AREA HOT LIGHT

MOST OF MODERN MEDICAL IMAGING DEPARTMENTS USE AUTOMATIC PROCESSORS—

MOST OF THOSE ARE DAYLIGHT PROCESSORS

AUTOMATIC DAYLIGHT PROCESSORS

AUTOMATIC DARKROOM PROCESSORS

AUTOMATIC DARKROOM PROCESSORS

MANUAL PROCESSING

DARKROOM

BASIC COMPONENTS OF DARKROOM

STORAGE SHELVES

WORKBENCH

BASIC COMPONENTS:PROCESSOR

BASIC COMPONENTS:CHEMISTRY MIXING TANKS

BASIC COMPONENTS:FILM DUPLICATOR

DUPLICATING FILM EXPOSED TO ULTRAVIOLET RADIATION

BASIC COMPONENTS:FILM FLASHER

BASIC COMPONENTS:SILVER RECOVERY SYSTEM

BASIC COMPONENTSFILM BIN

FILM BIN AUDIO ALARM

FILM BIN ANATOMY

CONTAINS INDIVIDUAL SLOTS THAT HOLD FILMS OF DIFFERENT SIZES

TYPICAL DARKROOM FILM BIN

14 x 17

FRONT

11 x 14

10 x 12

8 x 10

OTHER FILMS

RADIOGRAPHIC FILM SIZES

• 14 X17 • 11 x 14• 10 x 12• 8 x 10• 7 x 17• 6 x 12• 14 x 36

• 35 x 43• 28 x 35• 25 x 30• 20 x 25• 18 x 43• 15 x 30• 35 x 91

DARKROOM LIGHT

• WHITE LIGHTS

• SAFELIGHTS

WHITE LIGHT IS USED FOR:

EQUIPMENT REPAIR AND DARKROOM CLEANING

SAFELIGHTS USED

DURING FILM PROCESSING

SAFELIGHT BULBSINCANDESCENT RECESSED WITHIN METALLIC LIGHT

FIXTURE• RED FILTER-- KODAK GBX-2 OR GS-1

• AMBER FILTER --WRATTEN 6B

SAFELIGHTS

• RED—GREEN LIGHT SENSITIVE FILM ORTHOCHROMATIC

• AMBER –BLUE LIGHT SENSITIVE FILM

• TOTAL DARKNESS FOR PANCHROMATIC FILM

FILM TRAY

7.5 W

AT LEAST 3 FEET FROM THE FILM TRAY

FILM TRAY

15 W

AT LEAST 4 FEET FROM THE FILM TRAY

LATENSIFICATION

INCCREASED SENSITIVITY TO SAFELIGHT ILLUMINATION AFTER FILM WAS EXPOSED

DARKROOM DESIGN

LEAD SHIELDING IF ADJACENT TO X-RAY ROOM

• 1/16 INCH OF LEAD IN THE WALLS ALL THE WAY TO THE CEILING.

IF ADJACENT TO X-RAY ROOMS

• PASS-BOXES NEEDED TO PASS FILMS DIRECTLY FROM THE X-RAY ROOM TO DARKROOM

VENTILATION

• SYSTEM MUST BE LIGHTPROOF AND ABLE TO FILTER OUT DUST

HUMIDITY

• 40-60%

• > 60%--FILM FOG

• <40% STATIC ARTIFACTS

SIZE

• BIG ENOUGH!!!?

COLOR

• WALLS AND CEILING CAN BE PAINTED IN ANY COLOR

TEMPERATURE

• 50-70 º F FOR FILM STORAGE– TO SLOW DOWN THE AGING PROCESS OF THE FILM

WOULD YOU STORE IT LIKE THIS???

STORE YOUR FILMS STANDING ON THE EDGE TO AVOID

PRESSURE MARKS. USE FILM STORAGE CARTS OR SHELVES

COLOR OF THE MAZE

DARK-- NOT OT REFLECT WHIT LIGHT INTO THE DARKROOM

DARKROOM TESTING

• WHITE LIGHT LEAKS

• SAFELIGHT FOG

SAFELIGHT TEST

SENSITOMETRY

SENSITOMETRY-QUANTITATIVE MEASUREMENT OF FILM RESPONSE

TO EXPOSURE & DEVELOPMENT

FILM DEVELOPMENT

SENSITOMETRIC STRIPS

PRODUCING STRIP WITH PENETROMETER

PRODUCING STRIP WITH PENETROMETER

X-RAY TUBE

PRODUCING STRIP WITH SENSITOMETER

PRODUCING STRIP WITH SENSITOMETER

VISIBLE LIGHT

MEASURING DENSITY WITH DENSITOMETER

MEASURING DENSITY WITH DENSITOMETER

VISIBLE LIGHT

I o

I t

OD OPTICAL DENSITY

OD= LOG Io/I t

0.3 = 2 X DENSITY

OD vs % OF LIGHT TRANSMISSION

• 0• 1• 2• 3• 4

• 100• 10• 1• 0.1• 0.01

OD % TRANSMISSION

Characteristic curveCharacteristic curve, a curve used to show the exposure properties of a film or a film screen system. The characteristic curve, which was described in 1890 by Hurter and Driffield, is a representation of how the exposure of the film is related to the measurable signal, i.e. the blackening of the film, or film density. The characteristic curve is different for different film types but has a general shape as shown in Fig.1. The base and fog density is measured on an unexposed film. The shape of the characteristic curve tells the user the contrast properties (slope of the linear part) and the useful exposure range (length of the linear part). It also will indicate the speed of the film (or film-screen system), which can be judged from the curve's position along the horizontal axis. The speed class can also be found from the characteristic curve

SENSITOMETRIC CURVE

• H & D CURVE

• D Log E CURVE

• CHARACTERISTIC CURVE

SOLARIZATION

SYNERGISTIC REACTION

PHENIDONE

HYDROQUINONE

SOLARIZATION

FILM DUPLICATION

EXPOSURE TIME DENSITY

Base Plus Fog ( GROSS FOG, D min 0.15 -.20 OD)

The density of the unexposed film base plus any chemical fogging that may occur during

processing

Inertia Point

TRESHOLD

The point at which the film has absorbed sufficient light energy to start forming a

latent image.

ToeA non-linear region where shadow detail is recorded in negative materials (Highlight

detail in print material). Compression of the density differences occur and contrast is

decreased.

Straight Line Portion( GAMMA, SLOPE)

The linear section where most of the information is recorded. This section is used

to determine the processed contrast of the film.

RANGE OF USEFUL DENSITIES

0.25-2.0

Shoulder

A non-linear section. Compression of density differences occur and contrast is decreased. It

is unusual to record information on this region of the curve, however this region may

be reached with overexposure or extended development such as push processing to

increase effective film speed

QUANTITATIVE DATA OBTAINED FROM H&D CURVE

• FILM SPEED

• FILM CONTRAST

• B+F ( BASE PLUS FOG)

• EXPOSURE LATITUDE

FILM SPEED

SLOWSLOW

FASTFAST

FILM CONTRAST AVERAGE GRADIENT

A.G.= (OD2 – OD1)/ (LRE2 –LRE1)

FILM CONTRAST

STEEPNESS OF THE SLOPE

FILM CONTRAST AVERAGE GRADIENT

D2D2

D1D1

LRE2LRE2LRE1LRE1

FILM LATITUDE

LATITUDELATITUDELATITUDELATITUDE

CONTRAST VERY HIGH VISIBILITY OF DETAIL

VISIBILITY OF DETAIL vs CONTRAST

HIGH CONTRAST

LOW CONTRAST

PROCESSOR MONITORING

• DEVELOPER TEMP

• DEVELOPMENT TIME

.

• SPEED

• FOG

• CONTRAST

• FOG

• SPEED

• CONTRAST

THE AUTOMATIC PROCESSOR

AUTOMATIC PROCESSOR DAYLIGHT SYSTEM

PROCESSOR

SECTIONS OF THE PROCESSOR

DF

W

D

ENTRANCE ROLLERS

ENTRANCEROLLER

ENTRANCEROLLER

FILMS ORIENTATION ON THE TRAY

14 X 1711 X 1410 X 128 X 107 X 17

PROCESSOR SYSTEMS & SUBSYSTEMS

• TRANSPORT

• TEMP. CONTROL

• RECIRCULATION

• REPLENISHMENT

• DRYER

• ELECTRICAL

TRANSPORT

TRANSPORT FILM THROUGH PROCESSOR, REGULATION OF

IMMERSION TIME, AGITATE SOLUTIONS

TRANSPORT

ROLLER

GUIDE SHOE

RACKS

TURNAROUND ASSEMBLY

MASTER

GUIDE SHOE

TURNAROUND ASSEMBLY

MASTER ROLLER

GUIDE SHOE

SQUEEGE ROLLER

TEMPERATURE CONTROL—DRYER AND SOLUTION

TEMPERATURE

ELECTRICAL HEATER

TEMPERATURE VARIATION +- 5 DEG. FARENHEIT

TEMPERATURE

• DEVELOPER

• FIXER

• WASH

• DRYER

• 95 DEG F

• 95 DEG. F

• 90-95 DEG. F

• 135 DEG. F

TEMP. CONTROL

DRYER TEMP.

DRYER BLOWER RECIRCULATION

RECIRCULATION –AGITATION OF SOLUTIONS+ FILTRATION

PUMP

FILTER

RECIRCULATION

REPLENISHMENT SYSTEM

REPLENISHMENT

REPLENISHMENT PUMP

D F

REPLENISHMENT RATESFOR EVERY 14 IN. OF FILM

• 60-70 ML OF DEVELOPER

• 100-110 ML OF FIXER

PROCESSING TIME

+- 2 % VARIATION

• 45 SEC-210 SEC.

• MOST PROCESSORS DROP TIME 90 SEC.

RADIOGRAPHIC ARTIFACTS

TYPES OF ARTIFACTS

• PROCESSING

• EXPOSURE

• HANDLING AND STORAGE

PROCESSING ARTIFACTS

• HYPORETENTION• PI-LINES• GUIDE SHOE MARK• STATIC • ENTRANCE ROLLER MARK• CRINKLE MARK• FINGER MARKS• EMULSION PICK-OFF• WATER STAIN

EXPOSURE ARTIFACTS

• MOTION• IMPROPER POSITIONING• POOR FILM SCREEN CONTACT• DOUBLE EXPOSURE• FOREIGN OBJECTS• BACK-SCATTER• CASSETTE UPSIDE-DOWN• BROKEN CASSETTE• IMPROPER USE OF GRID

HANDLING & STORAGE ARTIFACTS

• LIGHT FOG

• RADIATION FOG

• STATIC

• SCRATCHES

• HYPORETENTION

FILMS STUCK TO EACH OTHER DURING PROCESSING

HYPORETENTION

PI-LINE

GUIDE SHOE MARK

STATIC

STATIC

STATIC

ROLLER MARKS

FINGER MARKS

CRIMPING MARK

PICK-OFF

WATER STAIN

WATER STAIN

POOR FILM SCREN CONTACT

H.T. (High Voltage) CABLES

DOUBLE EXPOSURE

BACKSCATTER OR CASSETTE UPSIDE-DOWN

BACKSCATTER

BACKSCATTER OR CASSETTE UPSIDE-DOWN

MOIRE EFFECT

WARPED CASSETTE-LIGHT LEAK

HAIR BUN

CLOTHES RIBBING

GRID CUT-OFF

JEWELLERY

SCATTER FOG

SANDBAG

FOGGING

KYPHOSIS-CHIN

STRAP

Q.A. TESTS

• COLLIMATION

• FOCAL SPOT SIZE

• KVP CALIBRATION

• EXPOSURE LINEARITY

• EXPOSURE REPRODUCIBILITY

• FILM-SCREEN CONTACT

• PROTECTIVE APPAREL INTEGRITY

COLLIMATION(LIGHT FIELD/RADIATION

FIELD CONGRUENCY)

• SEMI-ANUALLY

• NINE PENNY TEST OR SPECIAL TOOL TEST

• +- 2% OF SID

FOCAL SPOT SIZE

• ANNUALLY

• PINHOLE CAMERA, SLIT CAMERA, STAR PATTERN

• +- 50%

STAR PATTERN

LINE PAIR TEST TOOL

KVP CALLIBRATION

• ANNUALLY

• KVP METER

• +- 10%

KVP METER

EXPOSURE LINEARITY

• ANNUALLY

• DOSIMETER

• +- 10%

EXPOSURE REPRODUCIBILITY

• ANNUALLY

• RADIATION DOSIMETER

• +-5%

FILM/SCREEN CONTACT

• ANNUALLY

• WIRE MESH

• NO DARK AREAS PRESENT ON THE FILM

WIRE MESH

HOW USE WIRE MESH TO TEST FILM SCRREN CONTACT

CASSETTE

PROTECTIVE APPAREL

• ANNUALLY

• FLUORO

• NO CRACKS OR HOLES