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Reversible drawing .. How to process images .. Book of photography

How to process images
Reversible drawing

From positive images we can draw images directly onto paper or make second copies using reversible paper or film.

To make second copies of positive images, a piece called (reproduce) is required, or a reproducible, which is attached to the machine and there are various models of it. The simplest is the regular lens of the machine, while the most perfect uses a lens specially created for good color correction. If you only print second copies of positive images on special occasions, use ordinary reversible color film at medium speed. For more important production, it is better to buy a special film by the meter used for second copies: it is more economical and often gives better results.

Images are printed either on reversible paper or on paper called (color-killing paper). They are two completely different methods. Reversible paper has a similar concept to conventional color positive paper, while the other method uses pre-printed paper that contains colorants in each of its three layers: therefore, the unexposed paper is black. After exposure under a magnifier, the treatment partially destroys the colorants, but the unexposed colorants in each of the three layers form the color positive image.

Development is quite different from one method to another, so you must carefully follow the appropriate method of use.

- Completing images:

A color image can be rubbed, scraped and retouched as in black and white images. To scrape a color image for retouching, use a grayscale colorant because the grayscale white is invisible in the middle of a colored area. Tinting or shading a light secondary part or a touch of color on an insufficiently colored area can improve the final result. Depending on the technique, we can use liquid colors in tubes or in disc form.

- Reproducing positive images:
Clean the positive images you want to copy from after removing the protective cardboard if the reproducibility requires it.

Fix your camera on the reproducibility, which can accept most types of 24 x 36.

Make several different images - at least three - of each scene you want to copy. The film back.

- Printing on reversible paper:
Clean the positive image you want to enlarge carefully and then place it in the plate holder in the enlarger.

Expose the paper to the light. Some papers require correction by filtering. Refer to the manufacturer's list.

Appears in the recommended solutions. Some papers require re-exposure to white light during processing.

- Dry retouching:
We use colorants in tablet form for this. Several layers can be applied to obtain the desired color and value and we can also lighten or remove the color with (reducer). An additional color cancels out a colored reflection and an even similar color enhances the color value.

- Wet retouching:
This method is similar to watercolor painting: the sensitive surface absorbs the liquid that is placed on it, making any correction very difficult to stick. It is possible to re-wash the image to remove the colorants, but some papers change color when wet with water.

- Airbrush:
Using colors requires great skill and experience, we can get a wide or narrow area with this machine, this machine is available at painting equipment sellers.

- Using the air brush
Change the nozzle of the brush according to the desired line width and then protect the outer sections with a piece of cardboard.

Let the colors stick to the image with steam. Let it dry before starting your work again.

- Dry retouching:
Blow on the disc and then dip a piece of cotton in the now damp material.

Adhere the colorant to the surface of the image. Wipe off the excess with a rod with cotton tips dipped in (reducer).

Use steam to adhere the colorant to the image. Let it dry before working again.

Gently adhere the liquid colorant with a soft brush.

For large areas, use a wider brush filled with liquid.

Place the image in the fixative until the sensitive surface hardens. This fixative will not dissolve the colors if the immersion time is too short.