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التطوير والتثبيت .. المعالجة والطباعة بالأبيض والأسود .. المرشد خطوة بخطوة للتصوير الفوتوغرافي
Developing and fixing
Once the film is in the tank , you can carry out the processing in normal lighting . Have all the necessary equipment , shown right , ready before you start ; follow the manu- facturer's instructions for diluting and mixing the developer and , if necessary , the fixer . If your developer , fixer , or stop bath are re - usable , keep a record of the number of films they have processed .
The solutions must be kept at about 68 ° F ( 20 ° C ) during processing ; this can be done by standing them and the loaded tank in a tray of water at this temperature . Before starting , set the timer to the develop- ing time recommended for your film .
Equipment ready for processing
Thermometer
Tray containing water at 68 ° F ( 20 ° C )
Concertina bottle with funnel
Graduate containing developer
Rubber gloves
Stop bath
Fixer
Timer
Cap
Loaded developing tank
The processing sequence
1. Pour the developer in , holding the tank at an angle to allow air to escape .
2. Start the timer , then follow the tank manufacturer's instruc- tions for agitating the developer . Usually , you must tap the tank to dislodge air bubbles ; then put the cap on and at half , minute intervals turn the tank over and back , twice , throughout the development time .
3. At the end of the development time pour the developer out .
4. Fill the tank with stop bath , and agitate for 10 seconds , then leave the tank to stand in the tray of warm water for about one minute .
5. Pour out the stop bath . Water at 68 ° F ( 20 ° C ) , may be used instead of stop bath - fill the tank and agitate for 10 seconds empty and repeat .
6. Pour in fixer and agitate once every minute . Fixing time is usually at least 10 minutes . Return the fixer to its bottle ; the film must now be washed .
If you are using a plastic tank , agitate the solutions with the agitator rod . During the develop- ment time turn the rod alternately both ways for five seconds every half minute .
What happens during processing
When the exposed film is first removed from the camera , no record of the image is visible . This is because the film only receives enough exposure in the camera to form minute atoms of black silver in the light-sensitive silver halides . Processing acts as a form of amplification . Chemicals in the developer en- courage the formation of tiny filaments of black metallic silver so that the image appears .
The latent image
Before processing , a negative has an invisible , latent image of the picture which was ex- posed in the camera .
Development begins
Gradually those parts of the image which received most light appear as gray tones .
Full development
Mid - tones and shadow have now appeared ; highlights are much darker .
Stop bath or rinse
This stops further development by neutralizing or washing away the developer .
Fixing
The fixing solution dissolves the remaining undeveloped silver halides into colorless salts not sensitive to light .
The final image
The negative image has now cleared and can be looked at in normal light .
Developing and fixing
Once the film is in the tank , you can carry out the processing in normal lighting . Have all the necessary equipment , shown right , ready before you start ; follow the manu- facturer's instructions for diluting and mixing the developer and , if necessary , the fixer . If your developer , fixer , or stop bath are re - usable , keep a record of the number of films they have processed .
The solutions must be kept at about 68 ° F ( 20 ° C ) during processing ; this can be done by standing them and the loaded tank in a tray of water at this temperature . Before starting , set the timer to the develop- ing time recommended for your film .
Equipment ready for processing
Thermometer
Tray containing water at 68 ° F ( 20 ° C )
Concertina bottle with funnel
Graduate containing developer
Rubber gloves
Stop bath
Fixer
Timer
Cap
Loaded developing tank
The processing sequence
1. Pour the developer in , holding the tank at an angle to allow air to escape .
2. Start the timer , then follow the tank manufacturer's instruc- tions for agitating the developer . Usually , you must tap the tank to dislodge air bubbles ; then put the cap on and at half , minute intervals turn the tank over and back , twice , throughout the development time .
3. At the end of the development time pour the developer out .
4. Fill the tank with stop bath , and agitate for 10 seconds , then leave the tank to stand in the tray of warm water for about one minute .
5. Pour out the stop bath . Water at 68 ° F ( 20 ° C ) , may be used instead of stop bath - fill the tank and agitate for 10 seconds empty and repeat .
6. Pour in fixer and agitate once every minute . Fixing time is usually at least 10 minutes . Return the fixer to its bottle ; the film must now be washed .
If you are using a plastic tank , agitate the solutions with the agitator rod . During the develop- ment time turn the rod alternately both ways for five seconds every half minute .
What happens during processing
When the exposed film is first removed from the camera , no record of the image is visible . This is because the film only receives enough exposure in the camera to form minute atoms of black silver in the light-sensitive silver halides . Processing acts as a form of amplification . Chemicals in the developer en- courage the formation of tiny filaments of black metallic silver so that the image appears .
The latent image
Before processing , a negative has an invisible , latent image of the picture which was ex- posed in the camera .
Development begins
Gradually those parts of the image which received most light appear as gray tones .
Full development
Mid - tones and shadow have now appeared ; highlights are much darker .
Stop bath or rinse
This stops further development by neutralizing or washing away the developer .
Fixing
The fixing solution dissolves the remaining undeveloped silver halides into colorless salts not sensitive to light .
The final image
The negative image has now cleared and can be looked at in normal light .
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