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استخدام الفيلم بعناية .. اختيار الفيلم .. كيفية التقاط وتطوير الصور الملونة
CAREFUL FILM USE
Film always needs special care ; it is more delicate than any piece of camera equipment , and can easily be damaged by poor storage and careless handling . Colour film is more susceptible than black - and - white , as its colour balance depends on three layers of emulsion each being in perfect condition .
KEEPING FILM
The main precaution to guard against is ageing , which is accelerated by high temperature and humidity . In general , keep all unprocessed film cool and dry , and process it as quickly as possible . The best conditions for storing are below 16 ° C ( 60 ° F ) with a relative humidity between 40 and 60 % . For long - term storage , 4 ° C ( 40 ° F ) in a refrigerator is ideal , while a freezer set at -18 ° C ( 0 ° F ) will virtually halt any ageing . However , when you take the film out of really cold storage , do not open the film can immediately , but give it time ( up to an hour if it has been in a freezer ) to warm up gradually . Otherwise , condensation may form on the emulsion . Try not to keep film longer than the date marked on the packet , unless you freeze it as described .
If you are travelling with film , these conditions are not usually possible . In hot weather , a good alternative is a styrofoam picnic box , but in any case , keep the film out of direct sunlight , both to avoid overheating and to lessen the risk of light leaking onto the edges of the film ( this is more of a risk with 120 and 220 rollfilm than with 35mm ) . If the weather is humid as well , pack a sachet of silica gel crystals , which absorb moisture ; if film suffers from too much humid- ity , the emulsion becomes soft and swells .
X - RAYS
Security checks at airports are an unavoidable aspect of travelling with cameras and film . X - rays can fog film , and the effects are very similar to the fogging caused by light , but the doses given by most airport machines are too low if the film passes through only once . However , after several flights and X - ray checks before each one , then there is a real risk , particularly with high - speed colour film . Keep your film with you in your hand luggage and ask for an inspection by hand . In the United States and some other countries , you are entitled to this by law , but in most you have to rely upon the goodwill of the security staff . Lead - lined envelopes can be bought at photographic stores , but they are best as an emergency safeguard rather than as a regular procedure .
ABOVE A mobile refrigerator or electric cool box is ideal for keeping films cool on location . Unprocessed films should as a rule be kept at temperatures below 16 ° C ( 60 ° F ) , while a freezer set at -18 ° C ( 0 ° F ) should halt virtually any ageing . Even a styrofoam picnic box can prove a useful tool in keeping film cool .
LEFT While there remains debate over the extent of the damage caused by X - rays , there is no doubt that professional films in particular can be ruined by exposure to them . This chart shows the visual density changes in films caused by X - rays .
Visual density change in a film to one MR dose of ( based on Eastman Kodak Data ) X - rays
Note : The smallest Noticeable change is about 0.01
LOADING AND UNLOADING
Develop a set procedure , and do not rush . The greatest danger in loading is when the film tongue does not fit firmly in the groove of the take - up spool ; check that the film is running by watching the rewind knob as you wind the film on each time it should move . Having loaded the film , check that the film speed dial on the camera has been set correctly . Always load and unload in subdued light at all costs out of direct sunlight Remember that you can tell whether a camera contains film by twisting the rewind knob ; you will feel tension if it is loaded .
Loading
1. Open the camera back and pull out the rewind knob . In subdued light insert the film cassette so that the protruding end of the spool is at the bottom . Push back the rewind knob .
2. Pull out the film leader , and by rotating the take - up spool insert the end of the film into one of the slots , making sure that the perforations engage the lower sprocket .
3. Wind on the film until the top row of perforations engage the upper sprocket and the film is tensioned across the film guide rails .
4. Close the camera back and gently turn the film rewind knob in the direction of the arrow until you feel resistance . This is to check that the film is fully tensioned .
5. Advance the film two frames , making two blank exposures . The frame counter should now read " 0 " , Advance the film one more time and the first frame is ready for exposure .
6. Tear off the end of the film carton and place it in the holder on the back of the camera to remind you what type of film you are using .
Unloading
1. Press the rewind button . Unfold the film rewind crank and rotate it in the direction of the arrow . Continue to do this until you feel the tension ease . This indicates that the film has been fully rewound .
2 In subdued light , open the camera back . Pull out the rewind knob and take out the film cassette .
CAREFUL FILM USE
Film always needs special care ; it is more delicate than any piece of camera equipment , and can easily be damaged by poor storage and careless handling . Colour film is more susceptible than black - and - white , as its colour balance depends on three layers of emulsion each being in perfect condition .
KEEPING FILM
The main precaution to guard against is ageing , which is accelerated by high temperature and humidity . In general , keep all unprocessed film cool and dry , and process it as quickly as possible . The best conditions for storing are below 16 ° C ( 60 ° F ) with a relative humidity between 40 and 60 % . For long - term storage , 4 ° C ( 40 ° F ) in a refrigerator is ideal , while a freezer set at -18 ° C ( 0 ° F ) will virtually halt any ageing . However , when you take the film out of really cold storage , do not open the film can immediately , but give it time ( up to an hour if it has been in a freezer ) to warm up gradually . Otherwise , condensation may form on the emulsion . Try not to keep film longer than the date marked on the packet , unless you freeze it as described .
If you are travelling with film , these conditions are not usually possible . In hot weather , a good alternative is a styrofoam picnic box , but in any case , keep the film out of direct sunlight , both to avoid overheating and to lessen the risk of light leaking onto the edges of the film ( this is more of a risk with 120 and 220 rollfilm than with 35mm ) . If the weather is humid as well , pack a sachet of silica gel crystals , which absorb moisture ; if film suffers from too much humid- ity , the emulsion becomes soft and swells .
X - RAYS
Security checks at airports are an unavoidable aspect of travelling with cameras and film . X - rays can fog film , and the effects are very similar to the fogging caused by light , but the doses given by most airport machines are too low if the film passes through only once . However , after several flights and X - ray checks before each one , then there is a real risk , particularly with high - speed colour film . Keep your film with you in your hand luggage and ask for an inspection by hand . In the United States and some other countries , you are entitled to this by law , but in most you have to rely upon the goodwill of the security staff . Lead - lined envelopes can be bought at photographic stores , but they are best as an emergency safeguard rather than as a regular procedure .
ABOVE A mobile refrigerator or electric cool box is ideal for keeping films cool on location . Unprocessed films should as a rule be kept at temperatures below 16 ° C ( 60 ° F ) , while a freezer set at -18 ° C ( 0 ° F ) should halt virtually any ageing . Even a styrofoam picnic box can prove a useful tool in keeping film cool .
LEFT While there remains debate over the extent of the damage caused by X - rays , there is no doubt that professional films in particular can be ruined by exposure to them . This chart shows the visual density changes in films caused by X - rays .
Visual density change in a film to one MR dose of ( based on Eastman Kodak Data ) X - rays
Note : The smallest Noticeable change is about 0.01
LOADING AND UNLOADING
Develop a set procedure , and do not rush . The greatest danger in loading is when the film tongue does not fit firmly in the groove of the take - up spool ; check that the film is running by watching the rewind knob as you wind the film on each time it should move . Having loaded the film , check that the film speed dial on the camera has been set correctly . Always load and unload in subdued light at all costs out of direct sunlight Remember that you can tell whether a camera contains film by twisting the rewind knob ; you will feel tension if it is loaded .
Loading
1. Open the camera back and pull out the rewind knob . In subdued light insert the film cassette so that the protruding end of the spool is at the bottom . Push back the rewind knob .
2. Pull out the film leader , and by rotating the take - up spool insert the end of the film into one of the slots , making sure that the perforations engage the lower sprocket .
3. Wind on the film until the top row of perforations engage the upper sprocket and the film is tensioned across the film guide rails .
4. Close the camera back and gently turn the film rewind knob in the direction of the arrow until you feel resistance . This is to check that the film is fully tensioned .
5. Advance the film two frames , making two blank exposures . The frame counter should now read " 0 " , Advance the film one more time and the first frame is ready for exposure .
6. Tear off the end of the film carton and place it in the holder on the back of the camera to remind you what type of film you are using .
Unloading
1. Press the rewind button . Unfold the film rewind crank and rotate it in the direction of the arrow . Continue to do this until you feel the tension ease . This indicates that the film has been fully rewound .
2 In subdued light , open the camera back . Pull out the rewind knob and take out the film cassette .
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