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Methods of printing color photos - 1 - How to process photos .. Photography book

How to process photos
Methods of printing color photos

- The deletion method

This method requires only one exposure. It is preferred by professionals because it allows them to use normal techniques for enlargement, i.e. makeup.

The laboratory equipment for working with this method is more important than it is in the addition method. If you choose this method, the enlarger must be equipped with either a colored head with filters or a filter drawer (yellow - dark red - blue).

The enlargement process requires colored filters that enable the adjustment of the proportions of the primary colors present in the light source of the enlarger so that the color characteristics of the paper are consistent with the characteristics of the negative image. By means of the colored head, the filter values ​​​​appear on a disc, while if you use the filter drawer, you must form a collection of the necessary filters.

Before printing the final enlargement, a completely balanced experiment (color and density) must be conducted, and the experiments are conducted either by touch or by mosaic and finally by a color analyzer.

- Realization of experiments:

The set of experiments allows you to visually estimate the necessary filtration and exposure to obtain magnification: a principle similar to that of black and white. Each part of the experiment is large enough to judge the colors and quality of the image. For this, choose a distinct colored part.

- The first experiment - above - will be realized based on the filtration instructions given by the manufacturer of the paper and materials used. The experiment will be made with successive exposures (see page 190). This experiment will probably represent a dominant color.

- For the second experiment, adjust the filtration by adding the filter or filters whose color produces twice the dominant color in the first experiment. There will undoubtedly be a new value for exposure that must be calculated according to the instructions given. After processing, this second experiment should be approximately correct in terms of color and density.

- An insufficient adjustment of the dominant color will usually produce a color that is similar to that of the first experiment but less pronounced. Correction. Additional brings an additional dominant color: In this case, pull a filter value from the filter group. Same as the second experiment: The third experiment is often the best.

- When in doubt, make a fourth experiment so that a slight adjustment in the filter and/or exposure does not give a better result. Never enlarge the image before you have a complete and completely perfect experiment.

- The elimination method:
The elimination method consists of extracting the primary components of the white color. For example: A blue filter reduces part of the primary red light, but without stopping the green and blue lights. The percentage of light absorbed by the filter depends on the density of this filter.

- Magnifiers:
Most current amateur magnifiers are equipped with a drawer for filters for decreasing printing. A drawer located above the negative holder and the condenser.
The yellow, magenta (dark red) and blue decreasing filters are adjusted and placed in a drawer that adjusts the color of the white light source coming from the magnifier.
Some enlargers have changeable capacitors or can receive a broadcast filter: with broadcast light they are almost invisible: minor faults on the surface of the negative are visible with broadcast magnification, minor faults on the surface of the negative are almost invisible with magnification. Many manufacturers offer a colour head that is mounted on the enlarger or is part of it. The colour head is equipped with three buttons that allow the desired filter values ​​to be announced on dials.

Above - In most enlargers the filters can be placed between the negative and the light box and some have glass filters.
- Above and below -