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 Why Colors Don't Match
Viewing Color Around You
Using Our Online Color Systems
Save JPEG's as PSD to Preserve Quality
Sharpen The Edges And Leave The Rest Alone
Why colors don't match --
No device in a publishing or printing system is capable of reproducing the full range of colors viewable to the human eye. Each device operates
within a specific color space, which can produce a certain range, or gamut, of colors. Further, when you add hard material stocks and the backing colors, this
may also affect the manner is which a color is presented. Eg. Printing onto Business Cards is different to Printing Onto Banner Signs.
The RGB (red, green, blue) and CMYK (cyan, magenta, yellow, black) color modes represent two main categories of color spaces. The gamut's of the
RGB and CMYK spaces are very different; while the RGB gamut is generally larger (that is, capable of representing more colors) than CMYK, some CMYK colors still
fall outside the RGB gamut. (See Color gamut's (Photoshop) for an illustration.) In addition, different devices produce slightly different gamut's within the
same color mode. For example, a variety of RGB spaces can exist among scanners and monitors, and a variety of CMYK spaces can exist among printing presses.
Because of these varying color spaces, colors can shift in appearance as you transfer documents between different devices. Color variations can
result from different image sources (scanners and software produce art using different color spaces), differences in the way software applications define color,
differences in print media (newsprint paper reproduces a smaller gamut than magazine-quality paper), and other natural variations, such as manufacturing differences
in monitors or monitor age.
Color numbers
Each pixel in an image document has a set of color numbers that describe the pixel's location in a particular color mode--for example, red, green,
and blue values for the RGB mode. However, the actual appearance of the pixel may vary when output or displayed on different devices, because each device has
a particular way of translating the raw numbers into visual color. (See Why colors sometimes don't match.) When you apply color and tonal adjustments or convert
a document to a different color space, you are changing the document's color numbers.
Color profiles
An ICC workflow uses color profiles to determine how color numbers in a document translate to actual color appearances. A profile systematically
describes how color numbers map to a particular color space, usually that of a device such as a scanner, printer, or monitor. By associating, or tagging, a document
with a color profile, you provide a definition of actual color appearances in the document; changing the associated profile changes the color appearances. (For
information on displaying the current profile name in the status bar, see Displaying file and image information.) Documents without associated profiles are known
as untagged and contain only raw color numbers. When working with untagged documents, Photoshop uses the current working space profile to display and edit colors.
Viewing color around you.
View your documents in an environment that provides a consistent light level and color temperature. For example, the color characteristics of
sunlight change throughout the day and alter the way colors appear on your screen. You can also read the page about monitor colors on Page 4.
Some SOURCES: PHOTOSHOP HELP
Using our Online Color Systems
You can find more than 200 vinyl letter colors at our new online color system pages. Also, you can choose from over 30 different
Banner Material colors and find Pantone Colors Online at the PMS pages.
Save JPEGs as PSDs to preserve quality
If you start with a JPEG image, perhaps from a digital camera, and alter it, don't save it again as a JPEG; you'll lose image quality every time
you re-save an image in JPEG format. Instead, save the altered image as a PSD file and make a JPEG copy if you need to post the image to the web, for example.
In the meantime, you'll have a good copy of your altered image in PSD format for use in other applications, such as for printing photos or using them a printed
brochure.
NOTE: We only use Photoshop for creating images in pixel such as Photos. Graphics such as texts, logos and other artwork are always created in
vector formats. Outlines.
Sharpen just the edges and leave the rest alone
The Unsharp Mask filter is a wonderful tool if you don't mind increasing the sharpness of everything, including textures. On the other hand, if
you want the edges of objects to appear snappier, use the High Pass filter in combination with Unsharp Mask. To do so, duplicate your image and select Filter > Other >
High Pass. In the resulting dialog box, adjust the Radius slider to accentuate the edges. Try the lower values first--the image takes on a gray
appearance--and work up from there. Click OK. Then, change the Mode pop-up menu in the Layers palette to Overlay and observe the amount of edge sharpening that
takes place without affecting the flat or textured areas. If the effect is too strong, try the Soft Light blending mode and/or use the Opacity slider in the
Layers palette to reduce the intensity of edge sharpening.
Use the Measure tool to straighten out your images
When scanning images, you may have a scan that was a bit askew when you placed it on the scanner bed. It happens to us all. So, how do you straighten
it out? It's easy; simply use the Measure tool. Just drag the tool's pointer along the top edge of your image, then choose Image > Rotate Canvas > Arbitrary.
Click OK and Photoshop applies the information from your measurement and straightens things out for you.
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