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التصوير الفوتوغرافي الحديث
تقنيات الطباعة المتقدمة
مطبوعات كبيرة للغسيل والتجفيف
تقنيات التجفيف
DRYING TECHNIQUES
Since we are assuming that you do not have access to commercial print drying equipment as yet , we will confine our discussion of drying to methods which you may readily adapt to your specific circumstances . The number of prints to be dried , their size , whether they are dull or glossy , single or double weight , all affect the drying procedure . For that reason , no one method is recommended as best . Some of the more commonly used methods are discussed here .
To use a blotter roll , spread it open on a clean table or bench and place small weights at each end to hold it down so it doesn't curl . The corrugated paper should be at the bottom with the corrugated side up , followed by the linen - surfaced blotter with the cloth facing up . Now take the thoroughly washed prints one at a time , squeegee off all the surplus water on a sheet of plate glass or the bottom of a clean developing tray , and place the prints , face down , on the linen - surfaced blotter . Leave half an inch between small prints and a full inch between large all laid out , cover them with the unsurfaced blotter . Make sure the corrugated paper and the two blotters are lined up correctly , and then roll all three around the cardboard core . Tie a string around the bundle and set it aside for the prints to dry This usually takes overnight , unless the blotters are still damp from previous use .
Prints dried in a blotter roll have a slight outward curl at first , but this quickly disappears , leaving them flat and with no trace of warping or buckling .
DRYING GLOSSY PRINTS . If full gloss is not required , glossy prints may be dried in a blotter roll just as any others . The semi - gloss obtained in this way may be entirely satisfactory . If it is , the added trouble of ferrotyping can be avoided .. Generally speaking , however , glossy paper should be ferrotyped to give the maximum gloss .
Ferrotyping is the process of squeegeeing wet , glossy prints , face down , on an exceptionally smooth , flat plate so the soft emulsion dries perfectly shiny and even . The secret of successful ferrotyping is the use of a good , clean , ferrotype plate . Ferrotype plates come in two types : enameled and chromium plated . The enameled plate is cheaper and gives a slightly better gloss when new , but is easily scratched and dulled with use . Most photographers prefer the chromium plates .
If a ferrotype plate is new or has not been used for some time , it must first be washed thoroughly with soap and water . Dissolve enough soap flakes in warm water until the solution produces suds easily , and then wash the working surface of the plate . Rinse off the soap with plain water and dry with a clean cloth . Then apply a very thin coating of ferrotype polish with a dab of absorbent cotton and wipe it off again . This leaves a slight residue which prevents the prints from
sticking after they have been dried .
Figure 36 Placing washed but
undrained prints onto ferrotype plate .
Hold the polished ferrotype plate in the wash sink at a slight angle . Pick up the wet prints and quickly without draining place them face down on the ferrotype plate ( Figure 36 ) . If any print starts sliding off the plate , hold it a second or so until most of the surplus water drains off .
Put the plate down on a flat working surface and go over each print with a flat rubber squeegee as shown in Figure 37. If you do not have a rubber squeegee , use piece of heavy cardboard , but do not use a roller . It isn't necessary to use much pressure in squeezing out the surplus water - just enough to ensure good . contact between the print and the ferrotype plate . A hand roller cannot be relied upon to give positive contact . When the contact is poor , the dried prints will show small dull patches after they are dried .
Figure 37 Squeegeeing prints into firm contact with ferrotype plate .
Figure 38 After covering the ferrotype plate and prints , use a roller to dislodge any air bubbles that may be trapped under prints .
Drying may be hastened by blotting up all surface water or wiping it away carefully with a clean towel . In Figure 38 , surplus water is removed by placing a large blotter over the ferrotype plate and going over it with a print roller . The print roller in this case is used to help blot up the excess moisture and thus hasten drying . It is not relied on to insure perfect contact between the print and the ferrotype plate .
After that , lean the plate against a wall until the prints are dry . Drying can be hastened with a fan . In winter , when the relative humidity indoors is very low , the prints usually drop off by themselves when they are dry . They should be picked up immediately . If they are allowed to dry further , they curl badly . In summer , the dried prints may adhere lightly to the ferrotype plate , but should be peeled off as soon as they are dry . If allowed to remain on the plate too long , they may stick . The outer edges of a print dry first , the center last . If you try to peel a print from a ferrotype plate and you find that the center is stuck , the print probably is not completely dry . Wait a little longer and try again . If you peel off before it has dried thoroughly , the center will not have as full a gloss as the outer edges ..
There are a number of print dryers on the market which may be used quite successfully for small prints or a limited number of large ones . They consist of a chromium plated drum , or hollow platen , and a heavy canvas wrap - around . A heating element is built into the drum to hasten drying . Glossy prints are dried facing the chromium surface - others are dried facing the canvas . Drying time is usually quite short - generally a matter of minutes of large prints which can be accomodated at one time is not a particularly serious disadvantage for average use .
تقنيات الطباعة المتقدمة
مطبوعات كبيرة للغسيل والتجفيف
تقنيات التجفيف
DRYING TECHNIQUES
Since we are assuming that you do not have access to commercial print drying equipment as yet , we will confine our discussion of drying to methods which you may readily adapt to your specific circumstances . The number of prints to be dried , their size , whether they are dull or glossy , single or double weight , all affect the drying procedure . For that reason , no one method is recommended as best . Some of the more commonly used methods are discussed here .
To use a blotter roll , spread it open on a clean table or bench and place small weights at each end to hold it down so it doesn't curl . The corrugated paper should be at the bottom with the corrugated side up , followed by the linen - surfaced blotter with the cloth facing up . Now take the thoroughly washed prints one at a time , squeegee off all the surplus water on a sheet of plate glass or the bottom of a clean developing tray , and place the prints , face down , on the linen - surfaced blotter . Leave half an inch between small prints and a full inch between large all laid out , cover them with the unsurfaced blotter . Make sure the corrugated paper and the two blotters are lined up correctly , and then roll all three around the cardboard core . Tie a string around the bundle and set it aside for the prints to dry This usually takes overnight , unless the blotters are still damp from previous use .
Prints dried in a blotter roll have a slight outward curl at first , but this quickly disappears , leaving them flat and with no trace of warping or buckling .
DRYING GLOSSY PRINTS . If full gloss is not required , glossy prints may be dried in a blotter roll just as any others . The semi - gloss obtained in this way may be entirely satisfactory . If it is , the added trouble of ferrotyping can be avoided .. Generally speaking , however , glossy paper should be ferrotyped to give the maximum gloss .
Ferrotyping is the process of squeegeeing wet , glossy prints , face down , on an exceptionally smooth , flat plate so the soft emulsion dries perfectly shiny and even . The secret of successful ferrotyping is the use of a good , clean , ferrotype plate . Ferrotype plates come in two types : enameled and chromium plated . The enameled plate is cheaper and gives a slightly better gloss when new , but is easily scratched and dulled with use . Most photographers prefer the chromium plates .
If a ferrotype plate is new or has not been used for some time , it must first be washed thoroughly with soap and water . Dissolve enough soap flakes in warm water until the solution produces suds easily , and then wash the working surface of the plate . Rinse off the soap with plain water and dry with a clean cloth . Then apply a very thin coating of ferrotype polish with a dab of absorbent cotton and wipe it off again . This leaves a slight residue which prevents the prints from
sticking after they have been dried .
Figure 36 Placing washed but
undrained prints onto ferrotype plate .
Hold the polished ferrotype plate in the wash sink at a slight angle . Pick up the wet prints and quickly without draining place them face down on the ferrotype plate ( Figure 36 ) . If any print starts sliding off the plate , hold it a second or so until most of the surplus water drains off .
Put the plate down on a flat working surface and go over each print with a flat rubber squeegee as shown in Figure 37. If you do not have a rubber squeegee , use piece of heavy cardboard , but do not use a roller . It isn't necessary to use much pressure in squeezing out the surplus water - just enough to ensure good . contact between the print and the ferrotype plate . A hand roller cannot be relied upon to give positive contact . When the contact is poor , the dried prints will show small dull patches after they are dried .
Figure 37 Squeegeeing prints into firm contact with ferrotype plate .
Figure 38 After covering the ferrotype plate and prints , use a roller to dislodge any air bubbles that may be trapped under prints .
Drying may be hastened by blotting up all surface water or wiping it away carefully with a clean towel . In Figure 38 , surplus water is removed by placing a large blotter over the ferrotype plate and going over it with a print roller . The print roller in this case is used to help blot up the excess moisture and thus hasten drying . It is not relied on to insure perfect contact between the print and the ferrotype plate .
After that , lean the plate against a wall until the prints are dry . Drying can be hastened with a fan . In winter , when the relative humidity indoors is very low , the prints usually drop off by themselves when they are dry . They should be picked up immediately . If they are allowed to dry further , they curl badly . In summer , the dried prints may adhere lightly to the ferrotype plate , but should be peeled off as soon as they are dry . If allowed to remain on the plate too long , they may stick . The outer edges of a print dry first , the center last . If you try to peel a print from a ferrotype plate and you find that the center is stuck , the print probably is not completely dry . Wait a little longer and try again . If you peel off before it has dried thoroughly , the center will not have as full a gloss as the outer edges ..
There are a number of print dryers on the market which may be used quite successfully for small prints or a limited number of large ones . They consist of a chromium plated drum , or hollow platen , and a heavy canvas wrap - around . A heating element is built into the drum to hasten drying . Glossy prints are dried facing the chromium surface - others are dried facing the canvas . Drying time is usually quite short - generally a matter of minutes of large prints which can be accomodated at one time is not a particularly serious disadvantage for average use .
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