Darkroom

Question 1

what should the darkroom look like?

Answer 1

clean, lightproof, and free of chemical color
there is a wet side of the room and a dry side
walls and ceiling should be painted a light reflective color to maximize light from the safelight

Question 2

what is the dry side of the darkroom used for?

Answer 2

loading and unloading film from the cassette and for storage of unexposed films

Question 3

what is the wet side of the darkroom used for?

Answer 3

film that is being processed and hung to dry

Question 4

what should the door to the darkroom be able to do?

Answer 4

lock and open outward

Question 5

what are the two methods for the safelight in the darkroom?

Answer 5

direct lighting: safelight hung from wall facing workbench
indirect lighting: used when light is placed close to the ceiling and reflective paint helps light the room

Question 6

what are the two types of light filters?

Answer 6

blue light filters: filters out blue and ultraviolet light
green light filters: filters out blue and green light

Question 7

what type of light bulb should be used as the safelight in the darkroom?

Answer 7

a frosted 7-10 watt light bulb

Question 8

why should a ventilation fan be used in the darkroom?

Answer 8

to remove fumes and maintain temperature and humidity levels

Question 9

what does the automatic processor consist of?

Answer 9

film tray, developer, fixer and wash baths, dryers, rollers, basic gears, and replenishing pumps

Question 10

how do you process film?

Answer 10

1. place film into the tray
2. roller grabs it and sends it to the developing bath
3. moves to the fixer
4. moves to the wash bath
5. moves to the dryer
6. replenishing pump releases old developer and fixer

Question 11

how long does it usually take to process film?

Answer 11

90-120 seconds

Question 12

what does the developer do?

Answer 12

converts sensitized silver halide crystals into black metallic silver

Question 13

what are the components of the developer?

Answer 13

1. developing agents: phenidone (produces gray densities on the film), hydroquinone (increases contrast)
2. activator: sodium bicarbonate assists in maintaining pH of developer (should be alkaline)
3. restrainer: potassium bromide prevents developing agents from affecting crystals that weren’t activated by x-ray
4. preservative: sodium and potassium sulfite helps decrease risk of oxidation
5. hardener: adheres emulsion in film to base of film (prevents scratching and distortion)
6. solvent: distilled/ filtered water makes up 95-98% of the developer

Question 14

what does the fixer do?

Answer 14

removes unchanged halide crystals and stops the developing process

Question 15

what are the ingredients in the fixer?

Answer 15

1. fixing agent: made from sodium or ammonium thiosulfate
2. acidifier: made of acetic or sulfuric acid
3. preservative: made of sodium sulfite
4. hardener: made of potassium aluminum
5. solvent: water

Question 16

what do silver halide recovery units do?

Answer 16

remove the silver from the fixer as it leaves the processor
fixer flows from the machine into a jar where silver replaces iron in the steel wool through the release of electrons to silver halide which allows it to fuse to the iron in the steel wool

Question 17

what are a couple artifacts of processing film?

Answer 17

good density/ poor contrast: safelight error, light leaking into darkroom
poor density/ poor contrast: exhausted chemicals, chemical temperature is too cold