Printing - Black and White in Photoshop CS4 and Photoshop Lightroom - page 254

last as long as the blacks. There is some concern that over time the color inks
will fade at dif erent rates than the blacks. Depending on the purpose of the
print, this may or may not be a concern for you.
Grayscale
Mostly known today as Quadtone and Piezography, these are gray ink sets
designed to replace the color inks with various shades of gray in desktop
printers. Most of these grayscale inks use carbon as the pigment for the
black ink and create the lighter inks with various dilutions of the black
inkjet. These grayscale ink sets can produce astounding results, maintaining
neutrality throughout the entire tonal scale. As the carbon base is one of the
oldest photographic materials, grayscale ink sets have marked longevity -
considerably over 125 years. Although these ink sets can be purchased in
warm or cool tones, one is limited to the single tonality of the ink sets as
these inks are not easily toned in any other manner. Another consideration is
that Quadtone and Piezography inks are not yet distributed by major printer
manufacturers and must be obtained from third-party distributors, whereby
typically voiding your warranty on the printers if utilized. These inks also
require custom proi les. Some manufactures will provide them for certain
printer and paper combinations, while others do not.
Issues with Ink
Neutrality and Metamerism
As inkjet printers use a mixture of the colored inks in an attempt to create the
black and white tones, pigment inks historically tended to introduce slight
color casts to the prints, giving the inks the reputation of having an incapacity
for neutrality. Another issue for the black and white printer was the problem of
metamerism. Viewed under dif erent light sources of dif erent temperatures,
the ef ect of metamerism was to cause prints to dramatically shift color.
For example, a print could have a greenish cast when viewed in daylight, a
brownish cast under tungsten light on the market today and a magenta cast
when viewed under l uorescent lighting. The latest generation of pigment
inks on the market today, however, have improved tremendously. The days of
metamersim are mostly behind us and the capacity for printing neutral tones
from our desktop printers with the latest professional models has truly arrived.
Image Permanence
Image permanence, also referred to as longevity and stability, has always
been an important consideration in digital print making since the i rst i ne
art digital prints were created in 1989. Since then, there have been many
signii cant advances in the development of more permanent inks, making the
question of longevity less pertinent.
Today, the very best ink and paper combinations are rated at well over 100
years under normal display conditions and over 200 years in controlled
storage environments with acid-free materials.