Film Development Objectives: Describe what happens during the process of developing & fixing film Mix and store chemicals for darkroom Load tank in complete darkness Process film with developer , stop bath , fixer Wash /dry film

Development With chemicals in complete darkness After film goes through development – known as negative Light areas are dark, dark areas are light An error here can ruin film

developer stop bath fixer 3 basic chemicals Always In this order for film and paper

2. Dev causes emulsion to swell for better absorption of developer Developer changes exposed silver salts into black metallic silver that can be seen (gelatin silver print) Emulsion- dull side of film More fragile when wet Emulsion contains your image 1. Dev absorbs chemicals released during the change of salts to metallic silver 2. Dev causes emulsion to swell for better absorption of developer

Developer 68° ideal Develop longer if less than 68° . Cooler dev temp : add 1 min. per degree Develop shorter time if more than 68°. Warmer dev subtract : 1 min. per degree. Stop and Fix temps not as critical as DEV but should be within 3-5 ° of DEV temp. Black & white is forgiving. Your temps can be between 65 and 72 degrees. Adjust temp with tub warm or cool water to regulate the chemical temps Thermometer.

Stop bath= 30sec. Neutralizes, prevents further development of film. Weak acid solution – after developer Acetic acid Color indicator- yellow to purple

Fixer Fix dissolves all unexposed silver salts in the emulsion Makes images permanent! After fixing, film no longer reacts to light. Image can be seen Sometimes called “HYPO” sodium hyposulphite/ammonium thiosulphate rapid fixers, works faster

Fixer Do not expose film to light until fixing cycle is complete Fixer contain hardener (potassium alum) –firms and toughens emulsion Regular fixer 5-10minutes, rapid fixers 2-5 minutes Wash 60-75° water 10 minutes

Hypo clear Reduce wash time Saves water

Chemical terms Working life -period of time chemical retains it’s usefulness Stock solution- concentrate, that is, a solution to be diluted to some lower concentration for actual use Replenishers- to extend working life

Film grain

Dilution factors - with diluted developed, better grain results =Longer developing time Extreme temperatures cause graininess and uneven development

Dev tanks can be metal or plastic Plastic: have Ratchet type reel Exposed film is wound on reel in darkness

Put all equipment in changing bag. Remove film from canister with can or film opener. Tanks are light tight when put together correctly.

Agitate initially: 30 sec. Agitation= Rotation of the tank, for even development Cycle Agitate initially: 30 sec. Then 3 turns every 30 sec.

Stop -30 seconds, save Fix – 2 min., save Wash -10 min, cool water Hypo clear- removes fix chemically- discard & wash Wetting agent – (Kodak) photo flo prevents beading , watermarks- spots

Squeegee between fingers Dry film: clip both ends to reduce curl , dry 30min w/heat Keep film dust free (Even small specks of dust can scratch negative) Cut into 4-6 frame length Store in sleeves Hold film by edges Negative Care No finger prints!

Developing times for D-76 film developer 68 degrees Stock solution (no water) 6.5 min. Working solution : mix 1:1, 9.5 min.