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التصوير الفوتوغرافي الحديث
التقنيات المهنية المتقدمة ..
تحسين الطباعة ..
تطبيق FERRICYANIDE محليًا على المطبوعات
APPLYING FERRICYANIDE LOCALLY TO PRINTS
Ferricyaniding finds its greatest application in the treatment of local areas . It is easy to add accent lights to a portrait or perk up the clouds in a dramatic landscape by simply applying ferricyanide locally with a dab of cotton or spotting brush .
As in overall reduction , the hypo - ferricyanide reducer is recommended because it combines the advantages of ease of application , freedom from staining ( if properly used ) , and controllable action . Also , as in overall reduction , either the hypo and ferricyanide may be combined in one solution which is prepared just before use , or the print may be soaked in hypo and the ferricyanide applied separately . The choice between the two methods is determined by personal preference or the amount of work to be done . For only a slight amount of reduction , the hypo - laden print may be worked on while it is still fixing . For more extended work , it is best to dry the print so it can be examined more critically , after which it can be re - soaked and reduced with hypo - ferricyanide . solution . Both methods will be described .
REDUCING HYPO - LADEN PRINTS . For this you will need , in addition to the hypo tray , a glass squeegee plate or a steel enameled tray without chips or cracks , a small graduate or other container for the ferricyanide solution , some absorbent cotton , two spotting brushes - one large , the other small - and a soft rubber squeegee . ( See Figure 14 ) .
Figure 14 Equipment needed for local print reduction .
WORKING UP LARGE AREAS . For local reduction , a much stronger ferricyanide solution can be used than is required for overall reduction because the chemical action can be controlled more accurately . You will find a 20 to 1 dilution of the 10 % ferricyanide solution about as strong as you can safely control . You can use a stronger solution after a little experience , particularly if reduction is to be carried pretty far , but you will find it safer to start with a 20 or even 40 to I dilution . A 20 to 1 formula is obtained by putting one - fourth ounce of stock solution into 5 ounces of water ( 5 cc ferricyanide solution in 95 cc of water ) . This quantity of solution is more than you will require at any one session because a little ferricyanide goes a long way when applied with a swab of cotton .
Drop a small swab of cotton into the graduate of ferricyanide working solution so it is always ready for use , and keep a much larger swab of cotton immersed in a large tray of running water so you can rinse the ferricyanide off the print in a hurry when its action has gone far enough . Now proceed as follows :
Lift the print from the hypo tray and let it drain thoroughly . Place it face up . on the squeegee plate or bottom of the enameled steel tray and remove all surplus hypo with the rubber squeegee . This step is quite important . If you leave a pool of hypo over the area to be worked on , the action will be slowed up and reduction will extend beyond the desired zone .
Pick up the swab of ferricyanide laden cotton and squeeze most of the surplus back into the graduate so that the cotton is wet , but not dripping . Now touch the cotton to the center of the area you intend to lighten ( Figure 15 ) and , immediately on contact , start moving the cotton in a rotary or spiral motion , working from the inside out . This will prevent your work from showing , since the outer zones will have been in contact with the ferricyanide least , and so being least reduced , will blend in with the rest of the picture very smoothly .
Figure 15 Applying ferricyanide solution with a cotton swab .
In two or three seconds if you use a strong solution , or in five seconds if you use a weaker solution , douse the worked - up area with the dripping water - laden cotton swab or direct a stream of running water on it ( Figure 16 ) , and squeegee the print again . Be sure you do not leave any drops of water on the print , since they may contain enough ferricyanide to reduce the image and cause large round spots which you will find quite difficult to retouch .
If you have used a fairly strong ferricyanide solution , or if you have allowed it to work for a relatively long time so that it has soaked into the emulsion fairly well , it is best to repeat the swabbing with water - otherwise once is enough .
Figure 16 Rinsing off the ferricyanide solution .
Now examine the print to see if it has been sufficiently reduced . Watch the highlights carefully for the first signs of clear paper and a grainy image . When they appear , it is always a sure indication that you have gone too far . If more reduction is necessary , apply more ferricyanide , swab with water , and check again . After about three applications of ferricyanide , it is best to rinse the print thoroughly with lots of water , or better still , play the hose on it , drain and put it back in the hypo for a minute to soak up fresh hypo .
The procedure just outlined is used in working up fairly large areas . For smaller and more clearly defined areas , you can use a small swab of cotton pressed almost dry or a spotting brush . The brush will be found quite useful in taking out unwanted wrinkles and shadows in portraiture or putting in highlights along the forehead , the bridge of the nose and the chin .
Dip the spotting brush into the ferricyanide solution , wipe the surplus off on the side of the graduate so that the brush can come to a fine point , and then carefully apply the ferricyanide just where it is wanted . Hold the brush almost vertically so that you can control the area of contact with the paper more accurately . Do not press down too hard in an unconscious effort to speed up action you will only flatten the brush and spread the ferricyanide beyond the area you want to reduce . Instead , work the brush lightly up and back over the same spot for a few seconds . It is the chemical action and not the pressure that dissolves the image .
The few ounces of solution you started with will last for quite a long time , since it contained no hypo at first . However , as you use it , small quantities of hypo will be picked up from the prints , so that it will start to discolor after a time . When this begins to happen and the original bright lemon yellow becomes greenish , throw away the old solution and prepare a fresh batch .
التقنيات المهنية المتقدمة ..
تحسين الطباعة ..
تطبيق FERRICYANIDE محليًا على المطبوعات
APPLYING FERRICYANIDE LOCALLY TO PRINTS
Ferricyaniding finds its greatest application in the treatment of local areas . It is easy to add accent lights to a portrait or perk up the clouds in a dramatic landscape by simply applying ferricyanide locally with a dab of cotton or spotting brush .
As in overall reduction , the hypo - ferricyanide reducer is recommended because it combines the advantages of ease of application , freedom from staining ( if properly used ) , and controllable action . Also , as in overall reduction , either the hypo and ferricyanide may be combined in one solution which is prepared just before use , or the print may be soaked in hypo and the ferricyanide applied separately . The choice between the two methods is determined by personal preference or the amount of work to be done . For only a slight amount of reduction , the hypo - laden print may be worked on while it is still fixing . For more extended work , it is best to dry the print so it can be examined more critically , after which it can be re - soaked and reduced with hypo - ferricyanide . solution . Both methods will be described .
REDUCING HYPO - LADEN PRINTS . For this you will need , in addition to the hypo tray , a glass squeegee plate or a steel enameled tray without chips or cracks , a small graduate or other container for the ferricyanide solution , some absorbent cotton , two spotting brushes - one large , the other small - and a soft rubber squeegee . ( See Figure 14 ) .
Figure 14 Equipment needed for local print reduction .
WORKING UP LARGE AREAS . For local reduction , a much stronger ferricyanide solution can be used than is required for overall reduction because the chemical action can be controlled more accurately . You will find a 20 to 1 dilution of the 10 % ferricyanide solution about as strong as you can safely control . You can use a stronger solution after a little experience , particularly if reduction is to be carried pretty far , but you will find it safer to start with a 20 or even 40 to I dilution . A 20 to 1 formula is obtained by putting one - fourth ounce of stock solution into 5 ounces of water ( 5 cc ferricyanide solution in 95 cc of water ) . This quantity of solution is more than you will require at any one session because a little ferricyanide goes a long way when applied with a swab of cotton .
Drop a small swab of cotton into the graduate of ferricyanide working solution so it is always ready for use , and keep a much larger swab of cotton immersed in a large tray of running water so you can rinse the ferricyanide off the print in a hurry when its action has gone far enough . Now proceed as follows :
Lift the print from the hypo tray and let it drain thoroughly . Place it face up . on the squeegee plate or bottom of the enameled steel tray and remove all surplus hypo with the rubber squeegee . This step is quite important . If you leave a pool of hypo over the area to be worked on , the action will be slowed up and reduction will extend beyond the desired zone .
Pick up the swab of ferricyanide laden cotton and squeeze most of the surplus back into the graduate so that the cotton is wet , but not dripping . Now touch the cotton to the center of the area you intend to lighten ( Figure 15 ) and , immediately on contact , start moving the cotton in a rotary or spiral motion , working from the inside out . This will prevent your work from showing , since the outer zones will have been in contact with the ferricyanide least , and so being least reduced , will blend in with the rest of the picture very smoothly .
Figure 15 Applying ferricyanide solution with a cotton swab .
In two or three seconds if you use a strong solution , or in five seconds if you use a weaker solution , douse the worked - up area with the dripping water - laden cotton swab or direct a stream of running water on it ( Figure 16 ) , and squeegee the print again . Be sure you do not leave any drops of water on the print , since they may contain enough ferricyanide to reduce the image and cause large round spots which you will find quite difficult to retouch .
If you have used a fairly strong ferricyanide solution , or if you have allowed it to work for a relatively long time so that it has soaked into the emulsion fairly well , it is best to repeat the swabbing with water - otherwise once is enough .
Figure 16 Rinsing off the ferricyanide solution .
Now examine the print to see if it has been sufficiently reduced . Watch the highlights carefully for the first signs of clear paper and a grainy image . When they appear , it is always a sure indication that you have gone too far . If more reduction is necessary , apply more ferricyanide , swab with water , and check again . After about three applications of ferricyanide , it is best to rinse the print thoroughly with lots of water , or better still , play the hose on it , drain and put it back in the hypo for a minute to soak up fresh hypo .
The procedure just outlined is used in working up fairly large areas . For smaller and more clearly defined areas , you can use a small swab of cotton pressed almost dry or a spotting brush . The brush will be found quite useful in taking out unwanted wrinkles and shadows in portraiture or putting in highlights along the forehead , the bridge of the nose and the chin .
Dip the spotting brush into the ferricyanide solution , wipe the surplus off on the side of the graduate so that the brush can come to a fine point , and then carefully apply the ferricyanide just where it is wanted . Hold the brush almost vertically so that you can control the area of contact with the paper more accurately . Do not press down too hard in an unconscious effort to speed up action you will only flatten the brush and spread the ferricyanide beyond the area you want to reduce . Instead , work the brush lightly up and back over the same spot for a few seconds . It is the chemical action and not the pressure that dissolves the image .
The few ounces of solution you started with will last for quite a long time , since it contained no hypo at first . However , as you use it , small quantities of hypo will be picked up from the prints , so that it will start to discolor after a time . When this begins to happen and the original bright lemon yellow becomes greenish , throw away the old solution and prepare a fresh batch .
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