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التصوير الفوتوغرافي الحديث
تقنيات الطباعة المتقدمة
طباعة تصحيحية
إجراءات المراوغة
DODGING PROCEDURE
It is usually more convenient to dodge first those areas which are to be held back , since this can be done best when the initial overall exposure is being made . In our illustration , there are two such areas , marked I and II on our dodging guide .
The dodging guide shows that Area I is to be held back five seconds and Area II eight seconds , out of a total basic exposure of 20 seconds . This means that we can give our entire print at least seven seconds exposure , and that we must hold back five seconds in one place and eight seconds in another while we are giving the remaining 13 seconds exposure .
HOLDING BACK AREAS I AND II .
Area 1. Hold the round dodging mask ready , turn on the enlarger , and give an overall exposure of seven seconds . Then quickly place the dodger in position ( Figure 18 ) , so it casts a shadow which exactly covers the area to be held back . If you haven't an oblong or elliptical dodger , use a round one , but tilt it so it throws an elongated shadow rather than a round one . Keep the dodger moving up and down slightly so the held - back area will not have a sharp outline . The wire handle of the dodger will not cast any perceptible shadow , but to play safe , keep it moving over a fairly wide arc during exposure . When five seconds have elapsed , swing the filter in front of the enlarger lens while you get ready for the next operation .
Area II . For holding back this area , you need a small and narrow dodging disk . If your dodging kit doesn't include one , cut it out of cardboard to the shape of Area II , but make it somewhat smaller in size , and mount it on a wire handle with a piece of cellulose tape . Naturally , this should be done before you start .
Figure 18 . Using a round dodging mask to lighten Area I of Figure 17 .
Figure 19 Using a small , narrow dodging mask to hold back Area II .
making the enlargement . Hold this dodger so it casts a shadow over Area II ( Figure 19 ) , and swing the filter out of the way . Expose for another eight seconds .
Now Area II has been exposed for 12 seconds seconds , plus five seconds ) , and Area I has been exposed for 15 seconds ( seven seconds , plus five seconds , plus eight seconds ) . As a result , Area II will be the lightest , Area I will be somewhat darker , and the remainder of the print will be normal . Our next step is to print - in those areas which need darkening .
PRINTING - IN AREAS III AND IV .
Area III . As a general rule , it makes little difference which areas you darken first , although it is usually best to start with those that require the most dodging . In this case it is Area III .
The natural lighting for this subject was evidently badly out of balance , so the trees to the right were overexposed . Since these trees serve as part of a natural frame to set off the clouds and distant view , they must be darkened considerably with a gradual and imperceptible transition from maximum density near the edge of the print right up to the undodged center . The transition in tone must be smooth , with no sharp breaks or tone changes . An abrupt and obvious dodging line would call attention to itself , defeating the purpose of the dodging operation .
Hold the dodging card in front of the enlarger lens , halfway between the lens and paper so as to cut off all light . Turn on the enlarger and slowly move the card back from the edge of the print to the position shown in Figure 20. Then , without any hesitation , start moving it back toward the edge of the print at the same rate until the paper is again completely shaded . Repeat this printing - in operation until 20 seconds have elapsed . This will give you a perfectly smooth variation in exposure with no discernible sudden shifts in density . Watch the projected image below the card to be sure you are uncovering exactly the area you want to print - in .
Since the outside edge should be printed - in somewhat deeper than normal , move the card a little more slowly when exposing this area . When the 20 seconds have elapsed and you have completed your outward and inward movements , bring the card quickly up to the lens to cut off all light . Swing the filter in front of the lens and get ready to start on the next area .
Figure 20 Using card to darken side .
Area IV . The foreground in this picture is rather uninteresting . It is of value only because it leads the eye into the picture and toward the distant view .
Hold the dodging card so it exposes only the foreground , and move it in and out slightly to avoid a sharp line between the dodged and undodged area . Every second or so , move the card out until the entire print is masked , and then back again . This will give you some progressive darkening toward the edge and will help in framing the important central area .
The lower right hand corner will receive a double dose of printing - in , since it was already exposed with the right side . But this is all to the good . It helps the general effect by subduing the unimportant corner and compels the eye to travel into the lighter and more attractive central area .
PRINTING - IN AREAS V , VI , AND VII .
Areas V and VI . Now darken the left side and top , using the same procedure as for Area III , but keep the dodging as uniformly progressive as possible . It is usually a good idea to darken all four sides of practically every pictorial print to serve as a definite yet imperceptible frame . The human eye is attracted to the light and will always move from dark to light . Highlighted areas are areas of emphasis , and their effect is always increased when they stand out in contrast to darker areas . Motion pictures made of people's eyes looking at a picture with a uniform white streak running through it show that the eye keeps coming back to the disturbing streak and travels up and down it in a confused effort to decide which way to go . When the streak is darkened progressively toward one end , the eye moves along it in only one direction - toward the light . The result is a strong line of movement which helps the composition . This is clearly illustrated in Figure 21 .
The same effect , although on a much more gentle scale , is produced when the four sides of a print are darkened slightly . The eye is helped into the picture . where it belongs , and is not permitted to wander about unguided . Since a corner is always a stronger part of the picture than a side and is farther away from the center , the corners should be darkened even more than the sides .
Print - in the four sides one at a time at first . While this may take longer than the short cuts to be discussed later , it is much easier and permits more accurate . dodging . The four sides usually require different printing - in exposures , and it is rather difficult without considerable experience to print - in two or four sides at once and still keep their relative exposures correct . After a little practice , however , you can try dodging all four sides at one time by using a round or oblong disk on a wire .
Following the procedure for holding back areas as illustrated in Figure 18 , move the dodging disk through quite a distance between the lens and the paper to produce a gradual change in density from the edges to almost the center of the print . Twist or tilt the dodging disk if you want an elongated shadow instead of a round one . Similarly , if the bottom half of the print requires more printing - in than the top , which is usually the case , hold the dodger so its shadow is off center toward the top edge of the print , thus giving the bottom foreground a relatively longer printing - in time . With practice , you should be able to control dodging so well that you can give each of the four sides a different exposure if necessary .
Area VII . The upper right hand corner must be darkened considerably in order to complete the natural arch of the two trees coming together overhead . Ordinarily , printing - in the top and right side would darken the corner sufficiently ,
Figure 21 Progressively darkening upper part of this print prevents eye from following bright columns up and out of picture .
Figure 22 Using a card for progressive darkening of a corner ..
since it would be getting a double exposure but , in this instance , it is necessary to go much further . The same technique should be used as in darkening the top and bottom , except that the card should be held diagonally to the print as shown in Figure 22 .
تقنيات الطباعة المتقدمة
طباعة تصحيحية
إجراءات المراوغة
DODGING PROCEDURE
It is usually more convenient to dodge first those areas which are to be held back , since this can be done best when the initial overall exposure is being made . In our illustration , there are two such areas , marked I and II on our dodging guide .
The dodging guide shows that Area I is to be held back five seconds and Area II eight seconds , out of a total basic exposure of 20 seconds . This means that we can give our entire print at least seven seconds exposure , and that we must hold back five seconds in one place and eight seconds in another while we are giving the remaining 13 seconds exposure .
HOLDING BACK AREAS I AND II .
Area 1. Hold the round dodging mask ready , turn on the enlarger , and give an overall exposure of seven seconds . Then quickly place the dodger in position ( Figure 18 ) , so it casts a shadow which exactly covers the area to be held back . If you haven't an oblong or elliptical dodger , use a round one , but tilt it so it throws an elongated shadow rather than a round one . Keep the dodger moving up and down slightly so the held - back area will not have a sharp outline . The wire handle of the dodger will not cast any perceptible shadow , but to play safe , keep it moving over a fairly wide arc during exposure . When five seconds have elapsed , swing the filter in front of the enlarger lens while you get ready for the next operation .
Area II . For holding back this area , you need a small and narrow dodging disk . If your dodging kit doesn't include one , cut it out of cardboard to the shape of Area II , but make it somewhat smaller in size , and mount it on a wire handle with a piece of cellulose tape . Naturally , this should be done before you start .
Figure 18 . Using a round dodging mask to lighten Area I of Figure 17 .
Figure 19 Using a small , narrow dodging mask to hold back Area II .
making the enlargement . Hold this dodger so it casts a shadow over Area II ( Figure 19 ) , and swing the filter out of the way . Expose for another eight seconds .
Now Area II has been exposed for 12 seconds seconds , plus five seconds ) , and Area I has been exposed for 15 seconds ( seven seconds , plus five seconds , plus eight seconds ) . As a result , Area II will be the lightest , Area I will be somewhat darker , and the remainder of the print will be normal . Our next step is to print - in those areas which need darkening .
PRINTING - IN AREAS III AND IV .
Area III . As a general rule , it makes little difference which areas you darken first , although it is usually best to start with those that require the most dodging . In this case it is Area III .
The natural lighting for this subject was evidently badly out of balance , so the trees to the right were overexposed . Since these trees serve as part of a natural frame to set off the clouds and distant view , they must be darkened considerably with a gradual and imperceptible transition from maximum density near the edge of the print right up to the undodged center . The transition in tone must be smooth , with no sharp breaks or tone changes . An abrupt and obvious dodging line would call attention to itself , defeating the purpose of the dodging operation .
Hold the dodging card in front of the enlarger lens , halfway between the lens and paper so as to cut off all light . Turn on the enlarger and slowly move the card back from the edge of the print to the position shown in Figure 20. Then , without any hesitation , start moving it back toward the edge of the print at the same rate until the paper is again completely shaded . Repeat this printing - in operation until 20 seconds have elapsed . This will give you a perfectly smooth variation in exposure with no discernible sudden shifts in density . Watch the projected image below the card to be sure you are uncovering exactly the area you want to print - in .
Since the outside edge should be printed - in somewhat deeper than normal , move the card a little more slowly when exposing this area . When the 20 seconds have elapsed and you have completed your outward and inward movements , bring the card quickly up to the lens to cut off all light . Swing the filter in front of the lens and get ready to start on the next area .
Figure 20 Using card to darken side .
Area IV . The foreground in this picture is rather uninteresting . It is of value only because it leads the eye into the picture and toward the distant view .
Hold the dodging card so it exposes only the foreground , and move it in and out slightly to avoid a sharp line between the dodged and undodged area . Every second or so , move the card out until the entire print is masked , and then back again . This will give you some progressive darkening toward the edge and will help in framing the important central area .
The lower right hand corner will receive a double dose of printing - in , since it was already exposed with the right side . But this is all to the good . It helps the general effect by subduing the unimportant corner and compels the eye to travel into the lighter and more attractive central area .
PRINTING - IN AREAS V , VI , AND VII .
Areas V and VI . Now darken the left side and top , using the same procedure as for Area III , but keep the dodging as uniformly progressive as possible . It is usually a good idea to darken all four sides of practically every pictorial print to serve as a definite yet imperceptible frame . The human eye is attracted to the light and will always move from dark to light . Highlighted areas are areas of emphasis , and their effect is always increased when they stand out in contrast to darker areas . Motion pictures made of people's eyes looking at a picture with a uniform white streak running through it show that the eye keeps coming back to the disturbing streak and travels up and down it in a confused effort to decide which way to go . When the streak is darkened progressively toward one end , the eye moves along it in only one direction - toward the light . The result is a strong line of movement which helps the composition . This is clearly illustrated in Figure 21 .
The same effect , although on a much more gentle scale , is produced when the four sides of a print are darkened slightly . The eye is helped into the picture . where it belongs , and is not permitted to wander about unguided . Since a corner is always a stronger part of the picture than a side and is farther away from the center , the corners should be darkened even more than the sides .
Print - in the four sides one at a time at first . While this may take longer than the short cuts to be discussed later , it is much easier and permits more accurate . dodging . The four sides usually require different printing - in exposures , and it is rather difficult without considerable experience to print - in two or four sides at once and still keep their relative exposures correct . After a little practice , however , you can try dodging all four sides at one time by using a round or oblong disk on a wire .
Following the procedure for holding back areas as illustrated in Figure 18 , move the dodging disk through quite a distance between the lens and the paper to produce a gradual change in density from the edges to almost the center of the print . Twist or tilt the dodging disk if you want an elongated shadow instead of a round one . Similarly , if the bottom half of the print requires more printing - in than the top , which is usually the case , hold the dodger so its shadow is off center toward the top edge of the print , thus giving the bottom foreground a relatively longer printing - in time . With practice , you should be able to control dodging so well that you can give each of the four sides a different exposure if necessary .
Area VII . The upper right hand corner must be darkened considerably in order to complete the natural arch of the two trees coming together overhead . Ordinarily , printing - in the top and right side would darken the corner sufficiently ,
Figure 21 Progressively darkening upper part of this print prevents eye from following bright columns up and out of picture .
Figure 22 Using a card for progressive darkening of a corner ..
since it would be getting a double exposure but , in this instance , it is necessary to go much further . The same technique should be used as in darkening the top and bottom , except that the card should be held diagonally to the print as shown in Figure 22 .
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