Available online
Description
The chemistry of developing film and forming pigments in a transparency or print.
The chemistry of developing film and forming pigments in a transparency or print.
| Module code and title: | S304, The nature of chemistry |
|---|---|
| Item code: | S304; 17; 1978 |
| First transmission date: | 1978 |
| Published: | 1978 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:00 |
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| Producer: | David Jackson |
| Contributors: | Judith Bogie; Len Haynes |
| Publisher: | BBC Open University |
| Keyword(s): | Aromaticity; Chemistry; Colour; Film developing; Dyes; Light; Photography; Printing; Chemical reactions |
| Footage description: | Footage - Precipitation of silver bromide (0'14"-0'56") - Mock-up of Scheele's process (1'50"-3'10") - Silver halide particles exposed to light. Portrait of Sir John Hershel (3'23"-4'15") - Plate camera (4'50"-5'02") - Gelatin, silver nitrate & potassium bromide mixed to give silver halide, then melted and spread on cellulose-acetate (5'03"-6'08") - Negative illuminated on light box. Negative used to develop print (6'14"-8'04") - Graphic of equation silver halide acting as oxidising agent. Developing bath. Washing print. Fixing bath (8'19"-9'48") - Old faded print (10'20"-10'34") - Pyrogallic acid (10'40"-10'55") - Graphic of pyragallol formula. Print having silver bleached out. Graphic of reaction between oxidised developer and gelatin (11'07"-12'00") - Experiment to make yellow dye. Experiment to make yellow strip of film (12'22"-15'25") - Graphic of structure of cyan dye. Experiment to make cyan dye, then magenta dye. Graphic of structure of magenta dye (15'38"-17'17"). Composite picture made from three troughs of yellow, magenta & cyan dye (17'18"-18'15") - Projectors giving blue, green & red light (18'16"-19'03") - Camera from the turn of the century (19'25"-19'43") - Halide crystals (20'20"-20'44") - Graphic of layers of tripac film. Absorbed blue light. Red, green and blue light superimposed (20'59"-23'20"). |
| Master spool number: | 6HT/72427 |
| Production number: | 00525_1319 |
| Videofinder number: | 1267 |
| Available to public: | no |
