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Improving poor negatives
Technical mistakes which spoil your nega- tives are not always without remedy . As long as the image is not underexposed - and is therefore lacking in any detail ― or out - of- focus , or uneven in density , you may well be able to compensate after processing .
Underdevelopment , due to a timing error inaccurate processing temperatures , or ex- hausted processing solutions , may produce a pale , low contrast negative with almost ghost shapes . If you print such a negative on even the hardest grade paper it will give poor tonal range and contrast . To improve it you can use intensifying chemicals to bring out faint detail , improve contrast , and strengthen the image .
Hazy subject conditions , or overexposure combined with underdevelopment , may create a dark negative with low contrast . You can improve such results only by treating them with a chemical that reduces the overall density of the image .
Overdevelopment or harsh subject light- ing , or both , will produce very contrasty negatives . These will give hard , stark prints even on the softest grade printing paper . You can remedy this by combining the negative with a very pale positive image of itself , contact printed on film . This will mask out the harsh contrast in subsequent prints . Another remedy is to use a proportional reducing chemical on the negative which has most effect on the darkest parts of the image , reducing the contrast .
Before you give a negative extra chemical treatment , ensure the film is fully fixed and washed . All the chemicals for treating the negative can be used in normal lighting . If an entire film needs treatment , load it on to a developing tank reel and pour the solution into the tank . To treat a single negative , attach a clip to one corner so you can hold it in the solution .
Information for making up reducers and intensifiers is shown on page 213. Some intensifying and reducing chemicals are toxic . Handle them carefully and keep the solutions out of reach of children .
Reducing a dark negative
To lighten a dark , flat negative . such as shown top right , and im- prove its contrast , you can use ferricyanide " Farmer's reducer " . It reduces every tone by the same amount , as shown center right . Leave the negative in the solution for about five seconds , then rinse and examine . Repeat this until the density is correct .
Where less contrast is required , use a proportional reducer . This dissolves most silver from the dark- est areas of the negative , as shown right . It has a very slow action , taking about 20-30 minutes .
Intensifying a pale negative
To increase the density of a pale negative with faint detail , such as shown top right , use a chromium intensifier solution . This builds up the metallic silver image . Leave the film in the intensifier until it has bleached yellow . Wash the film and then transfer it to a tray of print developer for about 5 minutes to re - darken the image . Finally wash the film again . Intensification has a proportional result , having most effect on the darkest tones , as shown bottom right . Contrast is increased in the negative as well as density .
Negative masking
An alternative method for reduc ing contrast in a print , such as shown near right , is to mask the negative during printing . Make an underexposed contact print of the negative on to continuous tone . film , preferably a type such as Kodak Gravure Positive . Under- develop the contact print in diluted developer and process it - it will be a very weak , gray positive image , as shown bottom right . When printing combine this image in register with the original nega- tive . This will add tone to the shadows , giving a less contrasty print , as shown far right .
Improving poor negatives
Technical mistakes which spoil your nega- tives are not always without remedy . As long as the image is not underexposed - and is therefore lacking in any detail ― or out - of- focus , or uneven in density , you may well be able to compensate after processing .
Underdevelopment , due to a timing error inaccurate processing temperatures , or ex- hausted processing solutions , may produce a pale , low contrast negative with almost ghost shapes . If you print such a negative on even the hardest grade paper it will give poor tonal range and contrast . To improve it you can use intensifying chemicals to bring out faint detail , improve contrast , and strengthen the image .
Hazy subject conditions , or overexposure combined with underdevelopment , may create a dark negative with low contrast . You can improve such results only by treating them with a chemical that reduces the overall density of the image .
Overdevelopment or harsh subject light- ing , or both , will produce very contrasty negatives . These will give hard , stark prints even on the softest grade printing paper . You can remedy this by combining the negative with a very pale positive image of itself , contact printed on film . This will mask out the harsh contrast in subsequent prints . Another remedy is to use a proportional reducing chemical on the negative which has most effect on the darkest parts of the image , reducing the contrast .
Before you give a negative extra chemical treatment , ensure the film is fully fixed and washed . All the chemicals for treating the negative can be used in normal lighting . If an entire film needs treatment , load it on to a developing tank reel and pour the solution into the tank . To treat a single negative , attach a clip to one corner so you can hold it in the solution .
Information for making up reducers and intensifiers is shown on page 213. Some intensifying and reducing chemicals are toxic . Handle them carefully and keep the solutions out of reach of children .
Reducing a dark negative
To lighten a dark , flat negative . such as shown top right , and im- prove its contrast , you can use ferricyanide " Farmer's reducer " . It reduces every tone by the same amount , as shown center right . Leave the negative in the solution for about five seconds , then rinse and examine . Repeat this until the density is correct .
Where less contrast is required , use a proportional reducer . This dissolves most silver from the dark- est areas of the negative , as shown right . It has a very slow action , taking about 20-30 minutes .
Intensifying a pale negative
To increase the density of a pale negative with faint detail , such as shown top right , use a chromium intensifier solution . This builds up the metallic silver image . Leave the film in the intensifier until it has bleached yellow . Wash the film and then transfer it to a tray of print developer for about 5 minutes to re - darken the image . Finally wash the film again . Intensification has a proportional result , having most effect on the darkest tones , as shown bottom right . Contrast is increased in the negative as well as density .
Negative masking
An alternative method for reduc ing contrast in a print , such as shown near right , is to mask the negative during printing . Make an underexposed contact print of the negative on to continuous tone . film , preferably a type such as Kodak Gravure Positive . Under- develop the contact print in diluted developer and process it - it will be a very weak , gray positive image , as shown bottom right . When printing combine this image in register with the original nega- tive . This will add tone to the shadows , giving a less contrasty print , as shown far right .
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