تويت
التصوير الفوتوغرافي الحديث
تقنيات الطباعة المتقدمة
طباعة تصحيحية
دليل المراوغة
THE DODGING GUIDE
Whenever you are enlarging , your first print will be a straight trial print . The print of Figure 14 is such a trial print . Even a casual examination will tell you there is a lot of work to be done on it . In this particular case , the dodging requirements are quite complex . We have purposely chosen a complicated dodging job so we can cover the subject very thoroughly . Before any of this work is done , it is a good idea to make a dodging guide . This will consist of a sketch of the areas to be treated and notes on the desired treatment ( Figure 17 ) . Usually , however , the dodging to be done is quite simple , and you won't need a dodging guide .
If you have made the trial print previously so it is dry , you can make your notes right on the face of the print with a black crayon or soft pencil . If you prefer , you can work on the back of the print and make a simple , free - hand sketch of the picture . Outline all of the important areas and note what dodging is required . If the print is wet , make the dodging sketch on the back of a rejected print or a sheet of white paper .
In this Assignment , we will use the sketch method , and Figure 17 is the sketch we will use . The areas on the guide marked L are to be lightened . The areas marked D are to be darkened . The numbers after each letter indicate the dodging time in seconds on the basis of an overall basic exposure of 20 seconds .
For the purpose of this discussion , each area to be controlled is marked off and labeled with Roman numerals . While not necessary on your own guide , it makes it easier for us to explain the technique for printing to the correct density .
Now , after carefully examining the trial print , we have determined which areas should be lighter and which should be darker , and we have marked the dodging guide accordingly . Area I , marked L - 5 , will be exposed seconds less ( held back ) than the basic 20 - second exposure . Area II , marked L - 8 , will be
Figure 17 The dodging guide for corrective printing required to produce Figure 15 .
exposed eight seconds less than the basic exposure . Area III , marked D - 20 , will be exposed 20 seconds more ( printed - in ) than the basic exposure . Area IV , marked . D - 20 , will also be exposed 20 seconds more than the basic exposure . Areas V , VI , and VII , marked D - 10 , will be exposed ten seconds more than the basic exposure , and Area VIII , marked D - 5 , will be exposed five seconds more than the basic exposure .
In the areas to be printed - in , the lower right corner of the print will be exposed a total of 60 seconds ; 20 seconds for the basic exposure , 20 seconds for printing in Area III , and 20 seconds where Area IV overlaps Area III . Similar overlapping exposures will occur in each of the corners . This will darken the corners quite a good deal , but such darkening will help the compositional balance because the eye will then tend to move into the central picture area away from the dark sides and even darker corners .
When you make your own prints and must use your own judgment as to how much any area is to be made darker or lighter , bear the following in mind : any increase in exposure must always be considered in relation to the basic exposure . For example , with a basic exposure of 20 seconds , a printing - in time of 10 . seconds will result in a 50 % increase in exposure and produce noticeable darkening . The same 10 second printing - in time when the basic exposure is 60 seconds will result in an exposure increase of only 16-2 / 3 % , which is hardly noticeable . On the other hand , if the basic exposure is 5 seconds , a printing - in time of 10 seconds will triple the exposure and result in a considerable darkening . You must , therefore , always think of dodging time as a percentage or fraction of the basic exposure .
As a very rough guide , consider that a 25 % printing - in time will be barely noticeable , a 50 % printing - in time will produce quite noticeable darkening and a 100 % ( double ) printing - in time will produce strong darkening . The dodging times shown in the diagram of Figure 17 should be studied from that point of view .
THE VALUE OF THE DODGING GUIDE . If you have a complicated dodging job , it is a good idea to make a dodging guide . File it away with the negative . You will then always have it when you want to make another print . A dodging guide will save you a lot of time and paper . Without it , you will find it difficult to duplicate your pictures .
You can make a note on the dodging guide , giving the paper and developer used , as well as the enlarging exposures . It will still be necessary to make a test print to get the correct basic exposure for the current printing , but the exposure data will serve as a useful guide . Even if the same paper and developer are used , the times will not necessarily be identical , since paper speed varies between batches , and even changes with age in the same package . However , if the exposure is known for the first print , it narrows the guessing for the next .
تقنيات الطباعة المتقدمة
طباعة تصحيحية
دليل المراوغة
THE DODGING GUIDE
Whenever you are enlarging , your first print will be a straight trial print . The print of Figure 14 is such a trial print . Even a casual examination will tell you there is a lot of work to be done on it . In this particular case , the dodging requirements are quite complex . We have purposely chosen a complicated dodging job so we can cover the subject very thoroughly . Before any of this work is done , it is a good idea to make a dodging guide . This will consist of a sketch of the areas to be treated and notes on the desired treatment ( Figure 17 ) . Usually , however , the dodging to be done is quite simple , and you won't need a dodging guide .
If you have made the trial print previously so it is dry , you can make your notes right on the face of the print with a black crayon or soft pencil . If you prefer , you can work on the back of the print and make a simple , free - hand sketch of the picture . Outline all of the important areas and note what dodging is required . If the print is wet , make the dodging sketch on the back of a rejected print or a sheet of white paper .
In this Assignment , we will use the sketch method , and Figure 17 is the sketch we will use . The areas on the guide marked L are to be lightened . The areas marked D are to be darkened . The numbers after each letter indicate the dodging time in seconds on the basis of an overall basic exposure of 20 seconds .
For the purpose of this discussion , each area to be controlled is marked off and labeled with Roman numerals . While not necessary on your own guide , it makes it easier for us to explain the technique for printing to the correct density .
Now , after carefully examining the trial print , we have determined which areas should be lighter and which should be darker , and we have marked the dodging guide accordingly . Area I , marked L - 5 , will be exposed seconds less ( held back ) than the basic 20 - second exposure . Area II , marked L - 8 , will be
Figure 17 The dodging guide for corrective printing required to produce Figure 15 .
exposed eight seconds less than the basic exposure . Area III , marked D - 20 , will be exposed 20 seconds more ( printed - in ) than the basic exposure . Area IV , marked . D - 20 , will also be exposed 20 seconds more than the basic exposure . Areas V , VI , and VII , marked D - 10 , will be exposed ten seconds more than the basic exposure , and Area VIII , marked D - 5 , will be exposed five seconds more than the basic exposure .
In the areas to be printed - in , the lower right corner of the print will be exposed a total of 60 seconds ; 20 seconds for the basic exposure , 20 seconds for printing in Area III , and 20 seconds where Area IV overlaps Area III . Similar overlapping exposures will occur in each of the corners . This will darken the corners quite a good deal , but such darkening will help the compositional balance because the eye will then tend to move into the central picture area away from the dark sides and even darker corners .
When you make your own prints and must use your own judgment as to how much any area is to be made darker or lighter , bear the following in mind : any increase in exposure must always be considered in relation to the basic exposure . For example , with a basic exposure of 20 seconds , a printing - in time of 10 . seconds will result in a 50 % increase in exposure and produce noticeable darkening . The same 10 second printing - in time when the basic exposure is 60 seconds will result in an exposure increase of only 16-2 / 3 % , which is hardly noticeable . On the other hand , if the basic exposure is 5 seconds , a printing - in time of 10 seconds will triple the exposure and result in a considerable darkening . You must , therefore , always think of dodging time as a percentage or fraction of the basic exposure .
As a very rough guide , consider that a 25 % printing - in time will be barely noticeable , a 50 % printing - in time will produce quite noticeable darkening and a 100 % ( double ) printing - in time will produce strong darkening . The dodging times shown in the diagram of Figure 17 should be studied from that point of view .
THE VALUE OF THE DODGING GUIDE . If you have a complicated dodging job , it is a good idea to make a dodging guide . File it away with the negative . You will then always have it when you want to make another print . A dodging guide will save you a lot of time and paper . Without it , you will find it difficult to duplicate your pictures .
You can make a note on the dodging guide , giving the paper and developer used , as well as the enlarging exposures . It will still be necessary to make a test print to get the correct basic exposure for the current printing , but the exposure data will serve as a useful guide . Even if the same paper and developer are used , the times will not necessarily be identical , since paper speed varies between batches , and even changes with age in the same package . However , if the exposure is known for the first print , it narrows the guessing for the next .
تعليق