Paper, binding and materials

A photobook is a physical object, and its materials shape the reader's experience before a single image registers: the weight in the hands, the sound of a page turning, the way the book opens, the sheen or softness of the paper, the smell of ink. Materials also determine how images reproduce, how much the book costs to make and ship, and how long it lasts. PHOT-301 covered inkjet papers for fine prints; book papers for offset and digital presses are a different family, with different specifications and trade-offs. This lesson covers coated and uncoated book papers, how paper weight and thickness are specified in metric and North American systems, opacity, shade and grain, coatings and finishes, the main binding methods and cover options, and how to calculate spine width and book weight.

Coated and uncoated papers

Book papers fall into two broad families. Coated papers have a surface layer, usually of clay or calcium carbonate, that holds ink on the surface. This keeps ink dots sharp and produces rich blacks, saturated color and fine detail. Uncoated papers absorb ink into the fibers, so dots spread, colors look softer and blacks are less deep, but the paper feels natural, warm and tactile.

Choosing paper is a balance between reproduction quality and feel. A project of subtle tonal landscapes may need silk coated paper to hold shadow detail; a project about memory may gain meaning from a soft uncoated stock even if some detail is lost. Many books combine papers, for example silk for the plates and uncoated for an essay section. Always see printed samples on the actual paper; printers and paper merchants provide sample books and printed swatches.

Paper weight in grams and pounds

In Canada, Europe and most of the world, paper weight is given in grams per square meter (gsm or g/m²), a direct measure of mass per area. In the United States, and still widely in Canadian printing, paper is also described by basis weight in pounds: the weight of 500 sheets of the paper's basic sheet size. The basic size differs by grade, which is why a "100 lb text" paper and a "100 lb cover" paper are very different. Text papers use a basic sheet of 25 × 38 in; cover papers use 20 × 26 in.

Weight is not the same as thickness. Two papers of the same weight can differ in thickness, depending on fiber and surface; uncoated and bulky papers are thicker for their weight than coated papers. Thickness, called caliper, is measured in micrometers (µm) or millimeters in metric specifications and in thousandths of an inch, sometimes called points or mils, in North America.

Opacity, shade and show-through

Opacity is how much a paper blocks light. Low-opacity paper lets images on the reverse side show through, which is distracting in photobooks with dark images. Heavier, coated and bulkier papers tend to be more opaque. Paper specifications list opacity as a percentage; above about 94 percent is usually comfortable for photographic books with images on both sides of a leaf. If images print on only one side, as in books with blank versos, lower opacity may be acceptable, though the image can still ghost through to the blank page.

Shade is the color of the paper itself. Bright blue-white papers make colors look crisp and contrasty; natural or cream papers look warmer and softer. Many bright papers contain optical brightening agents, which fluoresce under ultraviolet light and can make the paper look different under daylight and gallery lighting. PHOT-301 discussed brighteners for inkjet papers; the same consideration applies to book papers, though books are usually viewed under mixed light at home.

Grain direction

Paper fibers line up along the direction the paper traveled through the papermaking machine. This is the grain direction. Paper folds and bends more easily along the grain, and it expands and contracts more across the grain with humidity. In a well-made book, the grain runs parallel to the spine. Cross-grain pages resist turning, crack when folded, and can cause the book to warp or the pages to wave. Printers manage grain direction when choosing press sheets, but custom sizes or unusual sheet layouts can force cross-grain pages. Ask your printer to confirm grain direction, especially for heavy papers and covers.

Coatings, varnishes and finishes

Printed pages and covers can be finished with coatings for protection or effect.

• Aqueous coating: a water-based clear coating applied on press that protects ink from scuffing and speeds drying.
• Varnish: an oil-based or UV-cured coating, either over the whole sheet (flood) or only on selected areas (spot), to add sheen or protection.
• Spot UV: a glossy, raised coating on selected areas, often used on covers for contrast with a matte background.
• Lamination: a thin plastic film bonded to the cover for durability, in gloss, matte or soft-touch finishes. Lamination adds plastic to the book, which some publishers now avoid for environmental reasons.
• Foil stamping, embossing and debossing: metallic or colored foil pressed into the cover, or raised and recessed shapes made with a die, common on cloth hardcovers.

Finishes should support the work. A soft-touch laminated cover feels luxurious but scuffs and shows fingerprints over time; an uncoated cover with a debossed title ages gracefully but marks more easily. Many photobooks use a simple uncoated cover or a cloth case with a printed tipped-on image, because these suit the reader's expectation of a crafted object.

Binding methods

Binding holds the pages together and determines how the book opens, how durable it is and how much it costs.

Saddle stitching suits zines up to about 64 pages on light paper; beyond that the fold becomes bulky. Perfect binding suits inexpensive softcovers but is the weakest choice for photobooks that need to open flat; PUR adhesive improves both strength and opening. Section sewing, where folded signatures are stitched together through the fold before gluing, is the traditional quality method and allows spreads to open well. Case binding produces a hardcover that protects the book and signals value. Swiss binding, where the cover is attached only at the back and the sewn spine is exposed, opens beautifully and has become popular in independent photobooks. Lay-flat bindings, common in print-on-demand photo books, open completely flat so images can cross the gutter without loss.

Covers and cases

Softcovers use a single heavy sheet, usually 250 to 350 gsm, scored and folded around the book block. French flaps, where the cover extends and folds inward at the front and back, add substance and a place for text. Hardcovers use rigid boards, commonly 2 to 3 mm thick, covered with printed paper (paper-over-board), cloth or other materials, with endpapers connecting the case to the book block. A dust jacket adds protection and a second layer of design, often carrying the title and blurb while the cloth case beneath stays simple. Slipcases, boxes and wraparound bands are used for special editions.

Each layer adds cost and weight. A cloth-covered hardcover with foil stamping, printed endpapers and a jacket may cost several times more to bind than a softcover. For a first self-published book, a well-made sewn softcover or Swiss binding often gives most of the quality at a fraction of the cost of a hardcover.

Calculating spine width

The spine width must be known before the cover can be designed, because the cover wraps around it. For a softcover, spine width is roughly the thickness of the book block plus a small allowance for the cover; for a hardcover, the case spine also allows for the boards and the rounding of the block. Printers supply exact figures after they choose the paper, but you can estimate early.

Here \( P \) is the number of pages, \( t \) is the caliper of one leaf (a leaf is two pages, front and back), and \( a \) is an allowance for cover and glue, typically about 0.5 to 1 mm for softcovers. North American printers often specify paper by pages per inch (PPI), the number of pages, counting both sides, in one inch of thickness. Then spine width in inches is approximately pages divided by PPI.

Book weight and shipping

Weight matters because shipping is a large part of the cost of selling books, especially across the border between Canada and the United States and to international buyers. Postal services and couriers price by weight and size bands, and a book that is slightly too heavy or thick can jump to a more expensive band. You can estimate the weight of the book block from the page area and paper weight.

Here \( A_{\text{page}} \) is the trimmed page area in square meters and \( g \) is the paper weight in grams per square meter. Add the cover and, for a hardcover, the boards and endpapers.

Sustainability and certification

Paper is the largest material component of a book, so paper choice matters most for environmental impact. Certifications such as the Forest Stewardship Council (FSC) and the Program for the Endorsement of Forest Certification (PEFC) indicate that fiber comes from responsibly managed sources; recycled papers reduce the use of virgin fiber. A printer must hold chain-of-custody certification to use the FSC logo on the book. Other choices include avoiding plastic lamination and shrink-wrap, using vegetable-based inks, and choosing a size and weight that reduce freight. Print the run you can realistically sell or distribute; unsold books that are pulped waste all the materials and energy that went into them.

Testing materials before committing

Before finalizing materials, ask the printer for a blank dummy: an unprinted copy made with your exact paper, extent, binding and cover. Hold it, open it, check how it lies on a table, feel its weight and see the spine width. Ask for printed samples of similar images on your chosen paper, ideally from books the printer has produced. If possible, visit a bookshop or library and handle books made with the papers and bindings you are considering. Materials that look good in a swatch book can feel different in a finished object.