Panasonic 8420 Reference Guide

							51 Managing Print Jobs
Using Fiery WebDownloader
Using Fiery WebDownloader, you can send PostScript or text files to the 
KX-P8420 without first opening the file in an application. 
NOTE:
•Fiery WebDownloader cannot be used on Macintosh computers.
A downloaded file can be sent to the Direct connection or to the Print or 
Hold queues. 
NOTES:
•The Direct connection can be used on printers without a hard disk drive or 
additional memory; however use of the Print and Hold queues requires a 
printer with a hard disk drive and 32 MB of memory.
•Files sent to the Direct connection are printed as soon as the printer is 
free to accept a print job. 
•Files sent to the Print queue are spooled to the printer’s hard disk drive. 
•Files sent to the Hold queue remain on the printer’s hard disk drive until 
they are moved to the Print queue or deleted. 
•PS or text files can be sent, but PCL files cannot.
•Font downloading is not available. 
						

							52 Managing Print Jobs
Downloading a file to the printer:
1Specify a file to download to the printer: 
Enter a path to the file you want to download to the printer in the 
Source File text field. Or click Browse to navigate to the file you want 
to download.
2From the Print Connection menu, select the connection 
to which you want to download.
If your printer does not have an optional hard disk drive, Print and 
Hold Queue options are dimmed in the Print Connection menu.
3Click the Send file button. 
The file is downloaded to the printer.  
						

							Chapter 5
53Working with Color
This chapter introduces concepts that are basic to color theory. You will 
encounter some of these concepts (such as hue, saturation, and 
brightness) when you work with color in applications; others provide useful 
background information. 
Color is a complex topic, so consider this a starting 
point for experimentation and further research.
The properties of color
What we call “color” is really a perceptual ability unique to humans and a 
small number of animal species. Color theory is an attempt to systematize 
the properties of color perception, which by nature is relative and 
changeable. A color appears different depending on the other colors around 
it, and individuals vary in their abilities to perceive color. 
The human eye can see electromagnetic radiation at wavelengths between 
400 nanometers (purplish blue) and 700 nanometers (red). This range is 
called the visible spectrum of light. We see pure spectral light as intensely 
saturated or pure colors. Sunlight at midday, which we perceive as white or 
neutral light, is composed of light from across the visible spectrum in more 
or less equal proportions. Shining sunlight through a prism separates it into 
its spectral components, resulting in the familiar rainbow of colors.
Like the sun, most light sources we encounter in our daily environment emit 
a mixture of many light wavelengths, although the particular distribution of 
wavelengths can vary considerably. Light from a tungsten light bulb, for 
example, contains much less blue light than sunlight. Tungsten light 
appears white to the human eye which, up to a point, can adjust to the 
different light sources. However, color objects appear different under 
tungsten light than they do under sunlight because of the different spectral 
makeup of the two light sources.
The mixture of light wavelengths emitted by a light source is reflected 
selectively by different objects. Different mixtures of reflected light appear 
as different colors. Some of these mixtures appear as relatively saturated 
colors, but most appear to us as grays or impure hues of a color.
The physics 
of color 
						

							Working with Color
54
In the 1930s, the Commission Internationale de l’Eclairage (CIE) defined a 
standard color space, a way of defining colors in mathematical terms, to 
help in the communication of color information. This color space is based on 
research on the nature of color perception. 
By mixing any two spectral colors in different proportions, we can create all 
the colors found between them. For example, it is possible to create the 
same gray by mixing blue-green and red light or by mixing yellow-green and 
blue-violet light. This is possible because of a phenomenon peculiar to color 
vision called metamerism. The eye does not distinguish individual 
wavelengths of light. Therefore, different combinations of spectral light can 
produce the same perceived color. 
A color can be described in terms of three varying characteristics: 
•Hue, or tint (the qualitative aspect of a color—red, green, or orange)
•Saturation, or the purity of the color
•Brightness, or relative position between white and black. 
Many computer applications include dialog boxes in which you select colors 
by manipulating hue, saturation, and brightness. For example, Photoshop 
uses a square Color Picker which can be reconfigured according to your 
preference.
CIE color model
Hue, saturation, 
and brightness 
						

							55 Working with Color
Color devices used in desktop publishing and printing simulate the range of 
visible colors using a set of primary colors that are combined to create other 
colors. There are two methods of creating a range of colors from a set of 
primary colors. Computer monitors and scanners use the additive color 
model. Printing technologies, including KX-P8420 print devices and offset 
presses, use the subtractive color model.
n Additive (RGB) color
Color devices that use the additive color model make a range of colors by 
combining varying amounts of red, green, and blue light. These colors are 
called the additive primaries. White is created by adding the maximum 
amount of red, green, and blue light available. Black occurs wherever all 
three colors are absent. Grays are created by adding varying amounts of all 
three colors together. Combining varying amounts of any two of the additive 
primaries creates a third, saturated hue.
A familiar device that uses this color model is the computer monitor. 
Monitors have red, green, and blue phosphors that emit varying amounts 
of light to display a given color. Scanners create digital representations of 
colors by measuring their red, green, and blue components through colored 
filters.
n Subtractive (CMY and CMYK) color
The subtractive color model is used in color printing, and in color 
photographic prints and transparencies. While the additive color model 
simulates the visible spectrum of color by adding light of three primary hues, 
the subtractive color model uses a “white” or neutral light source containing 
light of many wavelengths. Inks, toners, or other colorants are used to 
selectively absorb (subtract) certain wavelengths of light that otherwise 
would be reflected or transmitted by the media in question. 
The subtractive primaries are cyan, magenta, and yellow; they absorb 
red, green, and blue light, respectively. Combining any two subtractive 
primaries creates a new color that is relatively pure or saturated. For 
example, you can make red by combining magenta and yellow, which 
absorb green and blue light, respectively. White occurs when no colorant is 
applied. Combining all three subtractive primaries in theory yields black, but 
due to deficiencies of cyan, magenta, and yellow colorants, combining 
these three primaries actually yields a muddy brown. Black colorant is 
added to compensate for the deficiencies of cyan, magenta, and yellow 
colorants, and consequently color printing uses four process colors: Cyan, 
Magenta, Yellow, and blacK (CMYK). The use of black ink helps in 
producing rich solid blacks and also allows for improved rendition of black 
text.
Additive and 
subtractive 
color systems 
						

							Working with Color
56
Different color reproduction techniques have different color capabilities, or 
gamuts. Color transparency films have comparatively large gamuts, as do 
color monitors. The color gamut that can be produced using CMYK toners 
on paper is smaller. This is why some colors that can be displayed on a 
color monitor, especially bright saturated colors, cannot be reproduced 
exactly by your KX-P8420 print device—nor, for that matter, can they be 
reproduced on press using process colors. Moreover, different print devices 
have different gamuts—some colors that your print device can produce 
cannot be reproduced on an offset press, and vice versa. The following 
illustration provides a graphical representation of this concept.
You need to account for the gamut of your print device when designing on a 
color monitor. When printed, colors that fall outside the print device’s gamut 
are “mapped” to printable colors. This process, referred to as gamut 
mapping, takes place when color data is converted or adjusted to meet the 
color space and gamut requirements of a print device. 
The KX-P8420 Color Printer is specially designed to perform gamut 
mapping at high speed with high quality results. It provides these color 
management features automatically, using either built-in default settings or 
settings that you specify for a particular print job. For added flexibility, the 
KX-P8420 color management system can also be used in combination with 
color management systems on Macintosh and Windows computers.Print device 
gamut
Color transparency film
Other print deviceRGB monitor
Offset press (white) 
						

							57 Working with Color
Controlling printed color
When working with color materials, whether they be presentations, 
illustrations, or complicated page designs, you make aesthetic decisions 
about the colors you use. Once you have decided on your goal, you then 
need to realize it in print. Your color printing system becomes an ally in this 
creative process to the extent that you can get results that are 
predictable. 
•If you have designed a brochure to print on the KX-P8420, you want the 
printed colors to match the design specification.
•If you are printing presentations on the KX-P8420, you want to preserve 
the vivid colors in the monitor display. 
•If you are working with color that will print on press, you want the 
KX-P8420 output to match prepress proofs. 
The type of print job and the final print device either the KX-P8420 printer or 
an offset press, determine the methodology you use to achieve optimal 
results. 
No matter what your goals are, two hardware factors always impact color 
print output: print device consistency and the range of colors the print 
device can print, known as its gamut. These factors are covered briefly in 
this chapter. Creating successful color documents and presentations also 
requires an understanding of color management software as it is 
implemented by the KX-P8420 and on your desktop computer. Most of this 
chapter is devoted to discussing the various elements of color management 
that contribute to predictable color results. 
The factors described below affect print device consistency, as well as color 
fidelity and overall output quality.
The paper and toner used by the print device can greatly affect printed 
color. For best results, use the consumables recommended by the 
manufacturer of your printer. 
Problems such as streaking and insufficient or excessive amounts of one or 
more toners arise when a print device does not receive periodic 
maintenance. In addition to having it serviced regularly, monitor the color 
production of your printer by making standard test prints at regular intervals. 
You can do this easily by printing the KX-P8420 Test Page from the front 
panel. Save the prints and show them to your system or site administrator if 
recalibration becomes necessary.
Maintaining print 
device consistency
Paper stock and 
toner
Maintenance 
						

							Working with Color
58
Using color effectively
The ability to print in color can greatly increase the effectiveness of your 
message, whether you are printing a presentation or a newsletter, or 
proofing an ad concept that will later be printed on press. Some potential 
benefits of using color include:
•Conveying information rapidly by using color cues
•Making use of the emotive aspects of different colors
•Increasing impact and message retention 
Color can also be a source of distraction and discord if it is used poorly. 
This section outlines some tips and concepts that will prove useful as you 
approach designing color materials.
Try some of the following strategies for creating successful color materials:
•Rather than applying colors indiscriminately, use color to aid 
comprehension. In presentations, graphs, and charts, use color to 
highlight patterns and emphasize differences. 
•In general, fewer colors work better than many colors.
•Use red as an accent color. Red is particularly effective when used in 
otherwise monochromatic materials.
•Consider the tastes of your target audience when choosing colors. 
•Keep a file of printed color pieces that appeal to you or strike you as 
effective. Refer to it for ideas when designing your own documents.
A few rules 
of thumb 
						

							59 Working with Color
A color wheel is a helpful tool for understanding the interrelation of colors. 
The colors on one side of the color wheel, from magenta to yellow, appear 
to most people to be warm colors, while those on the other side, from green 
to blue, appear to be cool. The distance between two colors on the color 
wheel can help predict how they will appear when seen side by side. Colors 
opposite one another on the wheel are called complements, and create a 
striking contrast side by side. This can be the basis for a bold graphical 
design, but it is an effect you should use with discretion since it can be 
visually fatiguing. Other bold combinations to consider are split 
complements (a color and the two colors adjacent to its complement) and 
triads (three colors evenly spaced on the color wheel). Colors adjacent to 
one another on the color wheel result in subtle harmonies.
The color wheel simplifies color relationships for the purpose of clarity, 
showing only saturated or pure colors. Adding the myriad variations of each 
hue to the palette (more or less saturated, darker or lighter) creates a 
wealth of possibilities. Taking a pair of complements from the color wheel 
and varying the saturation and brightness of one or both colors produces a 
very different result from the pure complements. Combining a light tint of a 
warm color with a darker shade of its cooler complement often gives 
pleasing results. Combining a darker shade of a warm color with a light tint 
of its cooler complement produces an unusual effect you may like.
Once you have mastered the concept of the color wheel, you have a good 
framework for experimenting with color combinations. Many books targeted 
at graphic designers show groups of preselected color combinations. Some 
are organized by themes or moods, and some are based on a custom color 
system such as PANTONE. The more you develop a critical facility for 
judging color combinations, the more you will be able to trust your own eye 
for color.Color wheel 
						

							Working with Color
60
It is not a coincidence that the overwhelming majority of text you see is 
printed in black toner on white paper. Text in black on white is highly legible 
and is not fatiguing to read for extended periods. For many color materials, 
using black text on a white background and confining color to graphic 
elements and headings is a good choice.
Color text can add flair to documents printed on paper when used skillfully, 
and is widely used in presentations. When using color text, avoid dazzling 
text and background combinations created from primary complements, 
especially red and cyan or red and blue; they are visually fatiguing and hard 
to read. Color text is more legible when distinguished from its background 
by a difference in lightness—for example, dark blue text on a light beige 
background. In addition, using many different colors in a string of text 
makes for a confused appearance and is hard to read. However, using a 
single highlight color is an effective way to draw the reader’s eye to selected 
words.
When using color text, keep in mind that small font sizes typically do not 
print in color with the same sharpness as in black. In most applications, 
black text prints exclusively in black toner while color text usually prints with 
two or more toners. Any misregistration between the different toners on 
paper causes color text to lose definition. You can make test prints to find 
the smallest point size at which color text prints clearly. When using high-
end graphics applications that allow you to specify color as percentages of 
cyan, magenta, yellow, and black, you can create pure cyan or pure 
magenta text that prints with the same sharpness as black text. (Pure 
yellow text is extremely hard to read on anything but a dark or 
complementary background.)Color and text