Understanding Black and White Photographic Paper
Black and white photographic paper works similar to film. The paper contains silver halide crystals that turn black when exposed to light and developed. Parts that receive more light turn darker, resulting in an image with various monochrome tones from white to dark black. Although it's possible to use color photographic enlarging paper for black and white printing, you'll obtain better results from the different grades of black and white enlarging paper.
Choosing the Right Contrast Paper
High-contrast paper results in prints with strong black and white shades, with hardly any gray tones. Conversely, low-contrast paper has lots of gray with limited black and white tones. Paper grades are zero for low, three for medium, and five for high-contrast paper. Many photographers pick a paper grade that improves contrast; for example, choosing a high-contrast paper to boost a low-contrast negative. Alternatively, it's possible to use a variable contrast paper with magenta filters to obtain the best contrast.
Types of Photo Printing Paper
There are two main types of enlarger paper—resin-based and fiber-based. Resin-based paper develops quickly, and it's possible to use a roller dryer for fast drying, so it's ideal for low-cost, high-volume printing. Fiber-based paper takes longer to develop, and dries slowly because the chemicals saturate the paper, but its tones and colors are better, and the paper is more stable. A third, less common option is cotton-based enlarger paper used as darkroom display materials and specialty paper.
Effect of Different Paper Finishes
Glossy photo paper has a smooth, reflective surface that's suitable for highlighting fine details and emphasizing contrast. On the other hand, the coarse texture of matte photo paper softens images and hides minor imperfections. Between these two extremes is a range of semi-gloss photo papers with names such as satin, pearl, oyster, and velvet. They offer a nice compromise between the sharpness of a high-gloss finish and the softer characteristics of a full-matte finish.
Retouching Black and White Photo Paper
When enlarging small negatives, it's almost inevitable that there will be tiny imperfections caused by marks and specks of dirt on the negatives, especially when making large prints. You can remove defects with retouching supplies such as brushes or cleaning wipes. With care, you'll be able to hide or remove most defects. Thanks to a wide range of retouching inks, markers, pens, and pencils, it's possible to mask defects on lighter parts of prints, or even to remove them from negatives.