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الخطوة 4 : تحويل المطبوعات والشرائح .. معالجة الألوان والطباعة .. المرشد خطوة بخطوة للتصوير الفوتوغرافي
STEP 4 : CONVERTING PRINTS AND SLIDES
The type of film you use does not determine the form of your final image completely . You can make color slides and black and white or color prints from both color nega- tive and color slide film , although some- times with a loss in quality .
You can make color slides from color negatives by printing them on a print film . This film is like color paper but has a clear base . You can contact print or enlarge on to it like regular color paper - using similar filtering techniques . The resulting trans- parency should be processed in a similar way to a normal color print .
To make black and white prints from color negatives , you simply enlarge the negatives on to regular black and white printing paper . However this may distort the tonal reproduction of some colors . For the best results , you should use panchro- matic printing paper .
Slides can be made into color prints by making an intermediate color negative . This is formed by re - photographing the slide on to regular color negative film with copying equipment , shown below right . Some com- mercial processors will make negatives from slide film on special low contrast color inter- negative film ( this material is too complex for home use ) . You can also print color slides directly by using a special reversal printing material , explained on pages 173-5 .
Finally , black and white negatives can be made from slides by either copying direct or contact printing on normal , panchro- matic black and white film . ( If you slightly overexpose and underdevelop the film , this may compensate for the relatively high con- trast of the slides . ) Then the negatives can be printed on to regular bromide paper .
Color slides
You can make color slides from color negatives by using print film such as Ektacolor slide film or Ektacolor print film .
Black and white prints
Black and white prints can be made from color negatives by using regular or panchromatic bromide paper . From color slides you should make an intermed- iate black and white negative on a slow or medium speed film by copying , and print from this .
Color prints
Color prints can be made from color slides by enlarging them on to reversal printing materials ( see pp . 173-5 ) . Alternatively you can make an intermediate negative by copying the slide on color negative film , and then printing on to normal color paper .
Making black and white prints from color negatives
Regular bromide paper
If you enlarge a color negative on to regular bromide paper as in the picture , left , you should give three times the normal exposure for a black and white negative . There is some distortion in translating the colors into gray tones , because bromide paper is blue sensitive . In this print , red parts of the subject are much darker and blues are lost or are much lighter than they would normally be in black and white .
Panchromatic bromide paper
In the picture , left , the same color negative as above was printed on panchromatic paper . This paper reproduces the colors in the same tone values they would normally have on black and white film . The blue stripes in the background , for example , are now clearly visible . Panchromatic paper must be hand- led and processed in absolute dark- ness or dark green safelighting . As a result it should be processed in a developing drum .
Slide copying
The equipment below will copy slides same - size on black and white or color film . The copying tube , below left , has a close - up lens element which you attach over the camera lens . The color slide is held at the other end . The bellows copier , below right , in- cludes two adjustable bellows . One fits between the camera body and the lens , and the other between the lens and slide holder . This allows you to copy small areas , as well as complete slides .
Both units should be pointed toward an even light source . If color film is being exposed , the light source must be the correct color temperature for the type of film you are using .
Copying tube
Bellows extension copier
STEP 4 : CONVERTING PRINTS AND SLIDES
The type of film you use does not determine the form of your final image completely . You can make color slides and black and white or color prints from both color nega- tive and color slide film , although some- times with a loss in quality .
You can make color slides from color negatives by printing them on a print film . This film is like color paper but has a clear base . You can contact print or enlarge on to it like regular color paper - using similar filtering techniques . The resulting trans- parency should be processed in a similar way to a normal color print .
To make black and white prints from color negatives , you simply enlarge the negatives on to regular black and white printing paper . However this may distort the tonal reproduction of some colors . For the best results , you should use panchro- matic printing paper .
Slides can be made into color prints by making an intermediate color negative . This is formed by re - photographing the slide on to regular color negative film with copying equipment , shown below right . Some com- mercial processors will make negatives from slide film on special low contrast color inter- negative film ( this material is too complex for home use ) . You can also print color slides directly by using a special reversal printing material , explained on pages 173-5 .
Finally , black and white negatives can be made from slides by either copying direct or contact printing on normal , panchro- matic black and white film . ( If you slightly overexpose and underdevelop the film , this may compensate for the relatively high con- trast of the slides . ) Then the negatives can be printed on to regular bromide paper .
Color slides
You can make color slides from color negatives by using print film such as Ektacolor slide film or Ektacolor print film .
Black and white prints
Black and white prints can be made from color negatives by using regular or panchromatic bromide paper . From color slides you should make an intermed- iate black and white negative on a slow or medium speed film by copying , and print from this .
Color prints
Color prints can be made from color slides by enlarging them on to reversal printing materials ( see pp . 173-5 ) . Alternatively you can make an intermediate negative by copying the slide on color negative film , and then printing on to normal color paper .
Making black and white prints from color negatives
Regular bromide paper
If you enlarge a color negative on to regular bromide paper as in the picture , left , you should give three times the normal exposure for a black and white negative . There is some distortion in translating the colors into gray tones , because bromide paper is blue sensitive . In this print , red parts of the subject are much darker and blues are lost or are much lighter than they would normally be in black and white .
Panchromatic bromide paper
In the picture , left , the same color negative as above was printed on panchromatic paper . This paper reproduces the colors in the same tone values they would normally have on black and white film . The blue stripes in the background , for example , are now clearly visible . Panchromatic paper must be hand- led and processed in absolute dark- ness or dark green safelighting . As a result it should be processed in a developing drum .
Slide copying
The equipment below will copy slides same - size on black and white or color film . The copying tube , below left , has a close - up lens element which you attach over the camera lens . The color slide is held at the other end . The bellows copier , below right , in- cludes two adjustable bellows . One fits between the camera body and the lens , and the other between the lens and slide holder . This allows you to copy small areas , as well as complete slides .
Both units should be pointed toward an even light source . If color film is being exposed , the light source must be the correct color temperature for the type of film you are using .
Copying tube
Bellows extension copier
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