Cover Image

PART IV
Automatic


film processor






MODULE 11.0


Automatic film processor


Contents


a. General precautions
b. Preparation for maintenance
c. Daily maintenance
d. Weekly maintenance
e. Monthly maintenance
f. Quarterly maintenance
g. Annual inspection and service
h. Replacement parts schedule


Equipment required


■ An accurate thermometer (alcohol or electronic).
■ Hydrometer.
■ Sensitometer. (Or pre-exposed sensitometry film). *
■ Densitometer. (Or processed reference film for


comparison purposes). **
■ Chemical stirring rods. These may be stainless steel


or PVC. Important; the rods should be labelled
‘developer’ and ‘fixer’ to prevent cross contamina-
tion of chemicals.


■ Measuring cylinder. Graduated 100 ml glass or
plastic container.


■ Sodium hypochlorite bleach. (For monthly
maintenance).


■ Tank cleaning brushes, one each for developer and
fixer tanks.


■ Scouring pads. (Plastic or nylon type).
■ Clean disposable cloths.
■ Clean hand towels.
■ Plastic bucket.
■ Mop.


* A packet of pre-exposed sensitometry films may be
obtained from the film supplier.


** A previous processed sensitometry film may be used
as a reference.


PART IV. AUTOMATIC FILM PROCESSOR


147


Aim


The aim is to provide routine maintenance procedures
for the automatic film processor.This module presents
a series of regular maintenance schedules.When used
with sensitometry techniques, this module can be used
to implement a quality control programme.Repair pro-
cedures for the processor are provided in module 11.1
page 199.
(Note: Reference module page numbers refer to the
title page.)


Objectives


A processor maintenance schedule should be followed
regularly. Performing this maintenance will ensure
optimum quality of processed films, and allow detec-
tion of problems before they become serious. On com-
pletion of this module, the student will be familiar
with maintenance procedures for the automatic film
processor. These procedures should be used together
with the maintenance instructions in the operators’
manual. A routine maintenance check-sheet is pro-
vided in appendix ‘D’ page 186.


Note: This module is based on the procedures pre-
viously presented in the ‘Quality assurance workbook’.
As reference is made to sensitometry techniques, this
section from the WHO Quality assurance workbook is
included in appendix ‘A’ page 163.




a. General precautions


● Before removing any panels, ensure the processor
power is switched off. The processor power isolation
switch should also be turned off.


● All adjustable settings of the processor should be
recorded. This especially applies to microprocessor-
controlled systems. These have a large number of
settings, or options, and may develop an error. For
example, after a power failure, or due to incorrect
adjustment.


● The following items should be available for personal
protection.
i. Plastic apron.
ii. Coat to protect clothing from chemical splashes.
iii. Rubber gloves.
iv. Protective glasses and mask, to protect the face


from chemical splashes.
v. An emergency eye kit should be available in the


darkroom.
● Do not wear long loose clothing; this may become


caught in the rollers.
● Ensure that the darkroom is adequately ventilated.
● Clean up any spills or splashes.


b. Daily maintenance


● Before start up.
This assumes shutdown procedure was not perfor-
med, or the processor has been idle for some time.
i. Remove processor lid.
ii. Remove crossovers, and wash in warm water,


with a sponge or plastic cleaning pad. (Always
do developer first, then fixer, to avoid con-
tamination of developer.)


iii. Wash tank covers and splash guards.
iv. Wipe over all rack rollers that are above


solution levels.
v. Clean interior exposed surfaces.
vi. Check replenishment tanks/bottles levels.


Check for unusual colour or smell.
vii. Check replenishment hoses for possible leaks


or kinks.
viii. Replace the water drain standpipe, if


appropriate.
ix. Ensure the wash water drain valve is closed.


(Some processors may be fitted with an
automatic drain valve)


x. Turn on water, and check that wash tank is
filling. Time water flow if necessary.


xi. Note. Depending on make and model, water
flow will not commence until the unit is
powered up.


xii. Replace crossovers, and tank lids.


● On start up.
i. With the top cover removed, switch on the


processor.
ii. Note. Some processors have sensors, or


microswitches, to ensure the cover is correctly
fitted.With the lid off, you will need to activate
these switches manually.


iii. Listen for any unusual noise or vibration.
iv. Check film transport system. Ensure all rollers


are operating normally.
v. If not previously filled, check that wash water


is now filling correctly.
vi. Check replenishment system is working.
vii. Replace processor lid.
viii. Feed in one unprocessed 35 ¥ 43cm film as a


clean-up film.
Note. Do not use processed film, as these are
harder, and contain fixer.


ix. Inspect processed ‘clean up film’. Feed in a
second film if necessary.


x. Clean exterior surfaces, including feed tray and
receiving bin. Pay extra attention to the feed
tray.


xi. Wipe over all darkroom surfaces.
xii. When the processor has reached normal oper-


ating conditions, a routine sensitometry test
may be carried out. See appendix ‘A’, page 163.


● Normal working.
i. Follow manufacturers operating instructions.


(Read the manual.)
ii. Be aware of any changes in operation, noises,


leaks, or deterioration of processed films.
iii. Do not pull processed films out till they are clear


of the rollers.
iv. Always wait for the ‘ready’ signal or light before


feeding the next film.
v. When feeding films, insert the wide side as the


leading edge.The film should be lined up against
one side of the tray, not in the centre.


vi. Do not allow anyone to stand next to, or lean
on, the processor.


vii. Ensure the darkroom ventilation is correct, and
there is no build up of humidity or fumes. This
especially applies where a bench top processor
is used.


● On shut down.
i. Remove processor lid.
ii. Note. Some processors have sensors, or


microswitches, to ensure the cover is correctly
fitted. With the lid off, you will need to
activate these switches manually. Some pro-
cessors have several lid safety switches.Please
refer to the operating or service manual.


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148




iii. Observe transport system.
iv. Listen for any abnormal noise or vibration.
v. Observe level of solutions and wash water.
vi. Switch off.
vii. Look for any leaks.
vii. Remove and wash all crossovers, splashguards


and tank lids.
ix. Wipe over all rack rollers above solution level.


(Always do developer first, then fixer, to avoid
possible contamination of developer.)


x. Inspect and wash roller drive-cogs and drive
mechanism where appropriate.


xi. Replace tank lids. (Do not install crossovers.)
xii. Turn off wash water, if appropriate.
xiii. Remove water drain standpipe, if appropriate.
xiv. Wash off all chemical splashes on interior


exposed surfaces.
xv. Wipe any splashes from exterior surfaces.
xvi. Replace processor lid. Leave it slightly raised


at one end, to avoid build up of fumes and
condensation.


xvii. The darkroom door should be left open, with
the ventilation fan operating. (Depending on
power constraints.)


xviii. Place crossovers on top of processor, with
drain standpipe if appropriate, and cover with
a cloth; or store in a cupboard set aside for
that purpose.


xix. Observe levels of replenishment tanks. If
required prepare a fresh solution.


xx. Observe stocks of films, chemicals, or other
depleted supplies.Restock or order as required.


xxi. Record all restocking.
xxii. Report any problem or fault areas. See


module 11.1 page 151.
xxiii. Update the logbook


c.Weekly maintenance


● Follow manufacturers’ recommendations.
● Perform a sensitometry test. (For best control, this


should be performed as a daily routine.)
● Check solution temperatures, in particular devel-


oper temperatures. This is usually around 34~36
degrees Celsius
i. Note. Allow time for the temperature to fully


stabilize first.
ii. Compare with any readout on the processor


panel, and manufacturers’ recommendations.
iii. If outside the specified temperature limits,


compare to results previously recorded in the
logbook. Adjust if necessary.


iv. In case a drift of temperature is observed,
investigate further. Use the manufacturers


maintenance manual as a guide. See module
11.1 page 151.


● Check replenishment rates.
i. Remove processor lid
ii. Locate lid safety switches, if fitted. Place a


small weight, or else a small packing piece held
with tape, to keep these switches operated.


iii. Switch processor on.
iv. Divert the developer inlet to the tank, into a


100ml measuring-cylinder.
v. On some bench top processors, this may not be


possible. In which case divert the flow of used
developer from the tank, which would other-
wise go to the waste tank or the drain.
However, pass a least one film in first, to ensure
excess developer has commenced to flow.
Discard this initial measurement.


vi. Pass five 35 ¥ 43cm fresh films through the
processor. Do not use previously processed
films, as these are harder, and contain fixer.


vii. Divide the measuring cylinder contents by five,
to find the replenishment rate.


viii. Note. The above procedure is required for some
processors, which may not add individual
replenishment for each film inserted.This espe-
cially applies for microprocessor-controlled
units, which calculate several other factors
besides film size.


ix. Repeat the above for the fixer tank.
x. Record the results.
xi. Check with previous results for any significant


variation, or drift.
xii. Adjust if necessary.


● Remove and wash all deep rack rollers in warm
water
i. Particularly for the developer section, the rollers


may develop a layer of chemical crystals.A nylon
or plastic cleaning pad will assist in the removal
of these crystals, or ‘encrustation’.


ii. Inspect for correct function, wear or damage.
iii. Rinse and install.


● Check main drive shaft and chains or drive belt.
● Carry out any other maintenance recommended by


the manufacturer.
● Report any problem or fault areas. See module 11.1


page 151.
● Update the logbook


d. Monthly maintenance


● Follow manufacturers’ recommendations.
● Perform weekly maintenance.
● Inspect all racks and component parts during


cleaning.


PART IV. AUTOMATIC FILM PROCESSOR


149




● Clean filters.
● Drain all and clean all tanks.


i. Pay special attention to the wash water tank.
ii. The tanks may be filled with a dilute concen-


tration of 0.5% hypochlorite solution. An alter-
native is a system-cleaner chemical kit.This is a
two-part mix, plus a neutralizer, which is added
to the water when flushing out the cleaner.


iii. Let the solution sit in the system for no longer
than 30 minutes.


iv. Rinse the solution from the system,and dislodge
‘bio-growth’ or algae. Use a clean stiff brush or
other recommended tools to clean the surface.


v. Rinse the system thoroughly.
vi. Caution. Do not allow concentrated sodium


hypochlorite to come in contact with fixer or
developer. Dangerous fumes can result.


● Do not forget to add starter to the developer
tank.


● Manufacturers recommend replacement of all
chemicals on a monthly basis. This will especially
apply to developer, where oxidation continues even
when not in use. If recharging is not economic, then
inspect the condition of the solutions in the replen-
ishment tanks, and change as felt necessary.


● Carry out any other maintenance recommended by
the manufacturer, or felt necessary.


● Report any problem or fault areas. See module 11.1
page 151.


● Update the logbook.


e. Quarterly maintenance


● Follow manufacturers’ recommendations.
● Perform weekly and monthly maintenance.
● Discard remaining chemicals in replenishment tanks.
● Note. This especially applies to developer,which may


be oxidised. The developer will start to turn brown.


● Dispose of chemicals as required by local regula-
tions. Do not flush down the drain. Especially do not
discard so that seepage may end in a well, or in the
irrigation water.


● Wash out replenishment tanks, and flush hoses.
● Mix a fresh solution of developer and fixer.
● Note. Only mix sufficient developer to suit short


to medium term requirements. This will reduce
deterioration due to oxidation.


● Do not forget to add starter to the developer tank.
● Remove processor panels. Inspect carefully for any


leaks around pumps.
● Check overall condition of processor.
● Report any problem or fault areas. See module 11.1


page 151.
● Update the logbook.


f. Annual inspection and service


Even if you do not have a maintenance contract with
a service company, it is advisable to have the unit fully
inspected and serviced at least once each year. This
service should ensure that the processor is performing
to full specification. In addition, wear items such as
pump valves, especially for the fixer pump, can be
replaced. This service will also enable a new set of
reference sensitometry films to be obtained. Prior to
such service, it is recommended to have a fresh supply
of chemicals available. If film has been stored in
suspect conditions, a fresh pack of film should also be
on hand, to allow accurate calibration.


g. Replacement parts schedule


Manufacturers usually recommend replacement of
items subject to wear or deterioration. This should be
carried out at regular intervals. A typical example of
these items is provided in table 11–a.


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150


Table 11–a. A typical replacement parts schedule


Replace Each month Three months Six months Each year


Chemicals, developer and fixer. •


Replace fixer rack roller-springs. •


Replace entry, developer, wash •
and drying rack roller springs.


Replace developer rollers. •


Replace ‘poppet’ valves in •
replenishment pumps.


Developer filters. •


‘E’ rings. •




MODULE 11.1


Automatic film processor


sitometry is regularly performed during maintenance,
then deviations from the recorded characteristic curve
will aid diagnosis of film problems. The sensitometry
section from the WHO Quality assurance workbook is
included in appendix ‘A’ page 210.


Contents


a. Electrical precautions
b. Plumbing precautions
c. Suggestions for processor service or repair
d. The processed film appears dirty
e. Pressure marks on the film
f. Film is scratched or jammed
g. Film appears under developed
h. Uneven developing across the film
i. Film has high base fog and excessive contrast
j. Films appear poorly fixed
k. Films are discoloured. May appear ‘sticky’
l. Insufficient or uneven drying
m. Bands across the film, perpendicular to the film


transport direction
n. Film ‘fogging’
o. Static electricity marks


PART IV. AUTOMATIC FILM PROCESSOR


151


Aim


Many problems with the automatic film processor are
avoided by routine maintenance. Unfortunately, routine
maintenance may not be performed properly, or not at
all. This module provides a list of common problems
that may occur, and their solutions. Routine mainte-
nance procedures for the processor are provided in
module 11.0 page 147.
(Note: Reference module page numbers refer to the
title page.)


Objectives


On completion of this module, the student will be
familiar with film processor problems,and what to look
for when correcting these problems. In the event of a
problem, look also in the operation manual, for the
manufacturers advice.


(Task 16. ‘Films appear too dark’, and task 17 ‘Films
exhibit symptoms of low fixer’, should be attempted
on completion of this module).


Note: Detailed instructions for sensitometry are pro-
vided in the ‘WHO Quality assurance workbook’. If sen-


a. Electrical precautions


● Before removing any panels, or performing any
internal repair, ensure the processor power is
switched off. The processor power isolation switch
should also be turned off.


● An electrician or electronics technician should
perform any electrical tests or adjustments.


● If testing or replacing a fuse, see module 5.0 page
65.


● To make adjustments, it may be is necessary to
remove a module or printed circuit board (PCB),and
reconnect it with an extension board. This should
only be attempted on advice from the service
department.
i. Take care that power is switched off, before


proceeding.


ii. Before removing a module or PCB, touch the
processor frame. This is to discharge any static
electricity.


iii. Take note of plugs or sockets that may need to
be removed or reconnected. Do not rely on
memory. Make a diagram of the connections.
If connections or wires are not marked, attach
a temporary label.


iv. When a PCB is fitted to an extender card, take
care not to bump or dislodge it once power is
restored. Damage can result.


b. Plumbing precautions


Many plumbing problems in a processor may be
attended to, providing due care is taken. This can
include:




● Attention to plumbing or piping leaks.
● Replacement of replenishment-pump valves.
● Replacement of replenishment or recirculation


pumps.


Before attempting any repairs where the internal
piping or plumbing may be disconnected, take the
following precautions.


● Ensure the relevant processor tank has been
drained of any solution.


● Flush the system to remove any residual solution.
● Ensure the power is turned off, also at the power


isolation switch.
● Turn off the water supply to the processor.
● Make a diagram of piping connections before


removing. Attach labels for identification.
● Take care when disconnecting piping, not to lose


small ‘O’ rings. These can be hidden inside the
connection, and fall out later.


● When piping is disconnected, residual flushing
water will drain out. Be prepared, and place cloth,
or a towel, under the pipe before disconnecting.


● Have a bucket, or container, available for any
unexpected problem.


● Wear suitable protection clothing and gloves. See
module 11.0 page 147.


c. Suggestions for processor service or repair


● When diagnosing a problem, refer also to the oper-
ators or service manual for the processor. If in
doubt of the cause of a problem, request advice
from the manufacturers service division.


● Hint. When trying to locate a part in the processor,
refer to the diagrams in the parts manual.


● When replacement of a part is required, include any
auxiliary components that may be required. For
example, if replacing a faulty recirculation pump,
include replacement ‘O’ rings for the piping
connections.


● Place any small screws or parts in a container, to
avoid loss.


● All adjustable settings of the processor should be
recorded. This especially applies to microprocessor-
controlled systems. These have a large number of
settings, or options, and may develop an error. For
example, after a power failure, or due to incorrect
adjustment.


d.The processed film appears dirty


● The processing tank rollers are dirty.
i. Carry out the recommended weekly maintenance.


● Dirt or algae contamination of the wash water.
i. Replace wash water.
ii. Ensure wash water trough is clean.
iii. Examine the water supply filter, and either ‘back


flush’, or exchange the filter element.
iv. Check the water flow rate.
v. Check operation of the automatic drain valve.


(This is not fitted to all processors)
● Dirt or contamination of the processor solutions.


i. Carry out a complete cleaning procedure. See
module 11.0 page 147.


ii. Replace processor solutions. Make up a com-
plete fresh batch. Ensure filtered water is used.
Do not forget to add starter.


iii. Developer and fixer recirculation filters may be
fitted on some processors. These should be
cleaned weekly as part of routine maintenance.


iv. Some processors have a separate developer filter,
not installed in the tank. Depending on proces-
sor make or model, this filter should be changed
each year. If suspect, change immediately.


● A cleaning-film procedure has not been carried out.
i. This should be carried out each morning.
ii. Use a full size unprocessed film.


● The feed tray is dirty.


e. Pressure marks on the film


● Clean the film rollers.
● Pay special attention to developer rollers.
● Replace any rollers that do not have a smooth


surface, after cleaning.
● A pair of developer or fixer rollers may have


developed a flat, or uneven, area.
i. Test by slowly rolling along a flat surface. Feel


for any ‘bumps’ as the roller is rotated.
ii. Place a light behind the roller. Move the roller


along a flat surface. Look for any gaps as the
roller is rotated.


f. Film scratched or jammed


● With the top cover removed, feed a test film
through the processor.
i. Listen carefully for any unusual noise.
ii. Does the film jerk, or not move smoothly in any


area?
iii. Does the film exit partly rotated?


● Racks incorrectly installed.
i. Check the position and seating of the racks. Pay


careful attention to guide marks or grooves.
ii. Check that racks are not distorted, or bent out


of shape.


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152




● Loose or damaged roller pressure springs.
i. These are coiled springs shaped in the form of


a loop.They pull the rollers together, and provide
the correct pressure on the film.


ii. If springs are damaged, or have uneven tension,
then the rollers can feed the film at an angle.


iii. Compare the suspect spring to other springs.
Replace with a new pair, one on each side of the
rollers.


● Film crossover guides not properly installed or
faulty.
i. Examine the area around the guides for any


sharp edges, or scratched sections.
ii. Check the rollers. Ensure free movement of the


rollers.
iii. Check crossover alignment. Ask the service


department for advice, before making any
adjustment.


iv. Check crossover guides are correctly seated, no
distortion or cracks.


● Damaged gears.
i. A previous jammed film may result in broken or


damaged gear teeth. This can cause erratic or
stopped rotation of the rollers.


ii. A gear is not sitting in the correct position on
the shaft. Check for a missing retaining clip.
(Circlip).This fits in a groove of the shaft, to keep
the gear in position. Some gears have a plastic
retaining clip as part of the gear moulding. If
broken, the gear must be replaced.


● Incorrectly set drive shaft.
● Timing belt or chain incorrectly installed or broken.
● Sharp or damaged edges in the film entrance table.
● Incorrectly adjusted film entrance table.
● On systems with a micro-switch for film size


sensing, the actuation lever may be damaged.
● Films are fed too close together.


i. Does a warning light operate, until ready for the
next film?


ii. Does a chime sound when the processor is ready
for the next film?


g. Film appears under developed


● Operator error.
i. Wrong X-ray exposure setting.
ii. Incorrect cassette. Detail instead of normal


screens.
iii. Excessive starter was added after service.


● Insufficient developer replenishment. Check the
replenishment flow rate.
i. Replenishment pump not working.
ii. A leaky valve in the replenishment pump.


iii. The replenishment feed line is blocked. (Or
twisted and ‘kinked’)


iv. Faulty film size detection.
● The developer supply is oxidized or depleted.


i. Replace the developer supply, if more than one
month old.


ii. Test specific gravity. Use the temperature
correction chart, Fig C–1 page 177.


● Incorrect developer temperature.
i. Compare the temperature to the previous


recorded value, when the processor was last
serviced.


ii. Monitor developer temperature during the day.
Look for excessive temperature drift.


● Film transport speed has increased.
i. Check for incorrect settings in the processor


computer.
ii. Measure film transport time.
iii. Note. If transport speed is incorrect, this will


also affect fixing and drying.


h. Uneven developing across the film


● Recirculation pump not working.
● Partially blocked developer filter. Clean as part of


weekly maintenance.
● Damaged or blocked recirculation pipe lines.


i. Film has high base fog and excessive
contrast


● Operator error
i. Starter was not added after service. (Or


insufficient starter.)
ii. Add starter.


● Incorrect developer temperature.
i. Compare the temperature to the previous


recorded value, when the processor was last
serviced. Reset if required.


ii. Monitor developer temperature during the day.
Look for excessive temperature drift.


● Developer over concentrated.
i. Check supply specific gravity. Use the tempera-


ture correction chart, Fig C–1 page 177.
ii. Check replenishment rate.
iii. Add starter.


● Film transport speed has decreased.
i. Operator error. The speed adjustment was left


on low speed, after processing single emulsion
films.


ii. Check for incorrect settings in the processor
computer.


iii. Measure the film transport time.


PART IV. AUTOMATIC FILM PROCESSOR


153




iv. Motor speed may be reduced due to incorrectly
fitted racks.


v. Or motor speed may be reduced due to stiff
bearings. Lubricate the bearings. (The bearings
may be noisy).


j. Films appear poorly fixed


● Insufficient fixer replenishment.
i. Check the replenishment flow rate.
ii. Adjust the flow rate or pump operation time.
iii. Replenishment pump not working. Some


processors have two fixer replenishment pumps
working in parallel. One may be faulty.


iv. Faulty ‘Poppet’ valves on the replenishment
pump. Replace.


v. Replenishment feed line blocked. (Or twisted
and ‘kinked’)


vi. Faulty film size detection.
● Fixer supply incorrectly mixed.Check specific gravity.
● Fixer is contaminated, replace with a fresh solution.
● Fixer temperature too low. This may apply where


the processor has separate heaters for fixer and
developer.


● Poor ‘squeegee’ action of rollers as film exits the
developer tank. This leaves excessive developer on
the film, preventing proper contact with the fixer.
i. Clean the rollers.
ii. Examine the roller compression springs; ensure


correct fit and tension.
ii. Some processors have a ‘mini wash area’, with


the crossover rollers, where the film is trans-
ported between tanks. Ensure water level is
correct, and is circulated.


k. Films are discoloured. May appear ‘sticky’


● Fixer temperature too low. This may occur if
the processor has separate heaters for fixer and
developer.


● Fixer is depleted. See ‘Films appear poorly fixed’
● Wash water temperature too low.
● Film transport speed has increased.


i. Check for incorrect settings in the processor
computer.


ii. Measure the film transport time.
iii. Note. If transport speed is incorrect, this will


also affect developing and drying.


l. Insufficient or uneven drying


● Incorrect temperature setting. Temperature may
need to be increased if humidity level is high.


● The drying heater is faulty.
i. If more than one element, an element may be


burnt out.
ii. Faulty operation of the over-temperature safety


thermostat.
iii. Power fuse to the heater is open circuit.


● The drying fans are faulty. Possible failure of one fan
only.


● The drying thermostat is faulty.
● Fixer may be depleted, or at too low a temperature.
● Wash water temperature low.


m. Bands across the film, perpendicular to the
film transport direction


● Dirty rollers
i. Clean the rollers.The rollers may develop a layer


of chemical crystals. A nylon or plastic cleaning
pad will assist in the removal of these ‘crystals’,
or encrustation.


ii. Replace any rollers that do not have a smooth
surface after cleaning.


iii. Check for damage or flat areas on the rollers.
iv. Test by slowly rolling along a flat surface. Feel


for any bumps as the roller is rotated.
v. Position a light behind the roller. Move the roller


along a flat surface. Look for any gaps as the
roller is rotated.


● Rollers do not rotate smoothly.They stop and start.
i. The drive belt or chain may be loose. Adjust


according to the maintenance manual.
ii. Incorrect positioning of rack or rollers.
iii. A bearing may require cleaning, or lubrication.
iv. Damage to a gear tooth.


● Film is slipping in the rollers.
i. Examine roller compression springs; ensure


correct fit and tension.
ii. Look for missing springs.


The following film problems may not be due to the
processor.


n. Film fogging


● Darkroom safe light is faulty.
i. Test by leaving film on bench for a short time,


then processing. Next, place film directly into
processor, but keep safe light off.


ii. Aim the light upwards, away from the work-
bench or processor film table.


iii. Has the globe been replaced with a wrong type?
iv. Has the film been changed to orthochromatic


film? Contact the film supplier for advice. Obtain
correct filters for the safe light.


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154




● Damaged cassette, allowing light to enter.
i. Test by inserting a film in the suspect cassette,


with the safelight switched off. Then place the
cassette in different positions, in normal room
lighting.


ii. Process the film.
● All films appear fogged.


i. The film has been stored under excessive tem-
perature, or humidity conditions.


ii. The film has passed its expiration date.
● Film has intermittent fogging.Artefacts can also be


observed.
i. Scatter radiation is entering the cassette


storage area.
ii. Possible fault with radiation shield. Test by


placing a test cassette for a while in the suspect
area.


● Film exhibits fogging towards one edge only. All
films of the same size have a similar problem.
i. The film storage bin has been opened under full


lighting conditions.


ii. Possible light leak into the film storage bin.
Check for proper closing and operation of the
film bin.


iii. Improper light shielding of films, due to torn
packaging etc.


o. Static electricity marks


● These appear as ‘branched’, or ‘dotted’ areas on the
film.
i. This is due to a static discharge, as the film is


handled.
ii. A common cause is dry, or low humidity


conditions. Some floor coverings, and type of
shoes, can also cause this problem.


iii. Before handling the film, discharge yourself by
touching the metal tray of the processor.


iv. Use anti-static cleaners for the cassette
intensifier screens.


PART IV. AUTOMATIC FILM PROCESSOR


155




TASK 16


Films appear too dark


You have just returned from holidays. On using your normal exposure techniques, the films appear too dark. Your
assistant informs you she has also been having a problem, to obtain the correct exposures.


You suspect a problem with the processor. However, list possible reasons, not caused by the processor, which might
cause dark films.


Make a list of possible processor problems, which could cause a dark film. Indicate on this list the order in which
you would check these items.


Carry out suitable tests. Describe these tests and their results.


What action is needed to correct the problem?


Tutor’s comments


Satisfactory/Unsatisfactory


Signed Date


Tutor


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TASK 17


Films exhibit symptoms of
low fixer


After carrying out initial tests, you replaced the fixer, and adjusted the fixer pump. However, as several days go by
the problem repeats itself.
You come to the decision that the fixer pump is faulty and requires attention.


What were the original symptoms?


Describe the tests carried out, and action taken to correct the problem.


The problem has now repeated itself. You have contacted the processor agents, and discussed the problem. They
recommend you replace the pump valves, suspected leaking.You now have the replacement valves and are about
to affect a replacement.
Describe some important precautions before attempted disassembly


Reassembly has been successful. At the beginning you made some adjustments in an attempt to correct this
problem. Now with the processor powered up, and charged with fresh chemicals, what adjustment should again
be checked?


Tutor’s comments


Satisfactory/Unsatisfactory


Signed Date


Tutor


PART IV. AUTOMATIC FILM PROCESSOR


157




MODULE 11.2


The film ID printer


a. Operation of a film printer


The basic film printer consists of a lamp, which deliv-
ers a brief burst of light through the paper ID strip
onto the film. In its simplest form, a capacitor is
charged to a preset voltage. On closing the printer lid,
a microswitch connects the capacitor to the lamp,
producing a brief flash of light. A potentiometer con-
trols the voltage level on the capacitor, which in turn
controls the lamp output. Additions may include pre-
heating the lamp filament, or providing a flash timer.
Later versions replaced the lamp with a xenon flash
tube, similar to those employed in a camera. Due to
the simplicity of the design, very little can go wrong.
However, some problems may still occur.


b. Precautions for replacing the lamp


Before opening the cover ensure the printer is discon-
nected from the power point. Take care not to touch
any of the internal wiring, as there may be significant
voltage stored in a capacitor.


The replacement lamp should have a similar power
rating. Depending on the actual mode of operation,
changing to a higher rated lamp could produce a lower
flash intensity.


c. Failure to print


Before investigating, ensure the printer is unplugged
from the power point.


● Is the globe faulty? Try a replacement globe.
● Can you hear a small ‘click’ as the lid is closed?


If not the expose switch may need adjustment.
Otherwise the switch may be faulty.


● Does the power cord have a broken connection?
Check both at the plug end and where the cord
enters the printer. Repairs to the power cord or plug
should be performed by an electrician.


● Is the power point faulty? Check the printer in a
known good outlet.


● Has the print density control developed a bad
connection? Try adjusting to a different position.


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Aim


Film ID printers range from basic versions where the
film is first removed from the cassette,and then placed
in the printer, to motorized versions; which print the
film through a ‘window’ in the cassette. The sugges-
tions made here are for the basic version only.


Objectives


After completion of this module, simple repairs to a
basic film printer may be achieved.Assistance from an
electrician is recommended.


Contents


a. Operation of a film printer
b. Precautions for replacing the lamp
c. Failure to print
d. The printing is too light




d.The printing is too light


● Did this occur after changing the globe? Check to
ensure the correct type was fitted.


● Has the type of paper used for the patient ID been
changed to a different version?


● If the first printing attempt is light, but an attempt
at printing shortly after produces better results,


then a pre-heat resistor or adjustment may be
faulty. Have an electrician check for this possibility.
Do not attempt this by yourself; there may be a high
voltage charge on a capacitor.


PART IV. AUTOMATIC FILM PROCESSOR


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