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التبييض والتلوين .. تقنيات الغرف المظلمة المتقدمة .. المرشد خطوة بخطوة للتصوير الفوتوغرافي
Bleaching and toning
After processing the print there are still some chemical treatments you can use to alter its appearance . The two most important of these are bleaching and toning , both of which can be done in normal room lighting .
There are two useful bleachers - ferri- cyanide and iodine . You use ferricyanide to slightly reduce the density of dark areas of the print ; iodine erases parts of the image completely , leaving white paper . Toners change the black silver in the print into a compound of another color . They enable you to tint part of the image , leaving some areas black and white , or the whole image . Formula for making up bleachers and toners are shown in the table on page 213 .
Improving print contrast
You can apply ferricyanide ( " Far- mer's reducer " ) directly to prints , to make tones lighter . In the pic- ture , left , the sailboat needed to be picked out more strongly . The print was difficult to shade accurately while enlarging . So a straight . dark print was made and the sail was lightened , as shown below , by applying ferricyanide .
Local bleaching with ferricyanide
1. Make up the ferricyanide bleacher check its strength on a scrap print . Dampen your print and apply the bleacher on a brush or cotton swab .
2. Almost immediately swill over the print with water . Repeat this bleaching and washing until the area is the tone you want . Then re - fix and wash your print .
Bleaching areas from the print
You can use iodine bleacher to bleach out parts of the image from the print completely . You may want to isolate one element in a picture , like the two children shown left . The result , after bleaching , is a much stronger image , shown below . After applying the bleacher prints must be re - fixed and washed .
Bleaching out an image
1. Soak your print in water before applying the iodine solution . Use a cotton swab for treating broad areas and a brush for working in small areas .
2. You can see the area fading under the yellow stain of the iodine . When it is clear , remove the stain by re - fixing the print for 5 minutes , then wash .
Toning
Toning first bleaches the black image on a print , then , after wash- ing , re - darkens it in a chemical solution and adds an overall color , as shown far right . Sepia is the most popular and permanent toning color , although you can also buy toner kits for blue , green and other colors . Some of these may only color the print temporarily - in time the color fades . Prints chosen for sepia toning should have a rich range of tones with good blacks . The process lightens the image so make your print slightly dark .
Making a sepia - toned print
1. Immerse the print in the sepia toner bleach solution for 2-3 minutes until only a pale yellow- brown image remains .
2. Rinse the print and place it in the toner solution for 5 minutes . Finally wash and dry the print thoroughly .
Localized toning
A print will only accept tone where it has been bleached first . So by bleaching only limited areas you can add tone selectively . You can apply the bleach using a swab or brush , as shown right , or you can leave the print in the bleacher for a very short time , so that the darkest shadows remain black . Always rinse the print before placing it in the toner .
Assignment : Manipulating the print
Select several negatives which contain images that you feel may be combined to illustrate a theme , such as " nightmare " or " childhood " . Make prints that illustrate the theme in the following ways :
A. Sandwich two negatives together and enlarge them as one . You may find one suitable negative , then have to take a second picture specially . This enables you to get the subject at the right size and position in the frame .
B. Make a photogram and sandwich it with a negative for a combination print .
C. Print two or more negatives on to one piece of printing paper . Consider using images of very different scales .
D. Choose one negative and , using the intermediate film method , make sola- rized prints using different fogging times .
E. Using one of the prints produced above make a solarized print by contact printing the image on to printing paper .
F. Enlarge a slide ( either color or black and white ) and a black and white negative sandwiched together or separately on to a sheet of bromide paper .
With all the prints you produce con- sider using bleachers or toners , either selectively or overall to improve the image .
Bleaching and toning
After processing the print there are still some chemical treatments you can use to alter its appearance . The two most important of these are bleaching and toning , both of which can be done in normal room lighting .
There are two useful bleachers - ferri- cyanide and iodine . You use ferricyanide to slightly reduce the density of dark areas of the print ; iodine erases parts of the image completely , leaving white paper . Toners change the black silver in the print into a compound of another color . They enable you to tint part of the image , leaving some areas black and white , or the whole image . Formula for making up bleachers and toners are shown in the table on page 213 .
Improving print contrast
You can apply ferricyanide ( " Far- mer's reducer " ) directly to prints , to make tones lighter . In the pic- ture , left , the sailboat needed to be picked out more strongly . The print was difficult to shade accurately while enlarging . So a straight . dark print was made and the sail was lightened , as shown below , by applying ferricyanide .
Local bleaching with ferricyanide
1. Make up the ferricyanide bleacher check its strength on a scrap print . Dampen your print and apply the bleacher on a brush or cotton swab .
2. Almost immediately swill over the print with water . Repeat this bleaching and washing until the area is the tone you want . Then re - fix and wash your print .
Bleaching areas from the print
You can use iodine bleacher to bleach out parts of the image from the print completely . You may want to isolate one element in a picture , like the two children shown left . The result , after bleaching , is a much stronger image , shown below . After applying the bleacher prints must be re - fixed and washed .
Bleaching out an image
1. Soak your print in water before applying the iodine solution . Use a cotton swab for treating broad areas and a brush for working in small areas .
2. You can see the area fading under the yellow stain of the iodine . When it is clear , remove the stain by re - fixing the print for 5 minutes , then wash .
Toning
Toning first bleaches the black image on a print , then , after wash- ing , re - darkens it in a chemical solution and adds an overall color , as shown far right . Sepia is the most popular and permanent toning color , although you can also buy toner kits for blue , green and other colors . Some of these may only color the print temporarily - in time the color fades . Prints chosen for sepia toning should have a rich range of tones with good blacks . The process lightens the image so make your print slightly dark .
Making a sepia - toned print
1. Immerse the print in the sepia toner bleach solution for 2-3 minutes until only a pale yellow- brown image remains .
2. Rinse the print and place it in the toner solution for 5 minutes . Finally wash and dry the print thoroughly .
Localized toning
A print will only accept tone where it has been bleached first . So by bleaching only limited areas you can add tone selectively . You can apply the bleach using a swab or brush , as shown right , or you can leave the print in the bleacher for a very short time , so that the darkest shadows remain black . Always rinse the print before placing it in the toner .
Assignment : Manipulating the print
Select several negatives which contain images that you feel may be combined to illustrate a theme , such as " nightmare " or " childhood " . Make prints that illustrate the theme in the following ways :
A. Sandwich two negatives together and enlarge them as one . You may find one suitable negative , then have to take a second picture specially . This enables you to get the subject at the right size and position in the frame .
B. Make a photogram and sandwich it with a negative for a combination print .
C. Print two or more negatives on to one piece of printing paper . Consider using images of very different scales .
D. Choose one negative and , using the intermediate film method , make sola- rized prints using different fogging times .
E. Using one of the prints produced above make a solarized print by contact printing the image on to printing paper .
F. Enlarge a slide ( either color or black and white ) and a black and white negative sandwiched together or separately on to a sheet of bromide paper .
With all the prints you produce con- sider using bleachers or toners , either selectively or overall to improve the image .
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