Monday, December 15, 2008

Converting CMYK Black Type to 100% Black

Cmyk black type? What is it an why is it a problem? CMYK black type is something we see quite often. It generally happens when a file is generated in a Microsoft product (word, powerpoint, etc.) or when a file is exported to PDF with the wrong ICC Profile selected in your distiller jobsettings (recommended jobsettings can be download from our downloads page). It's a problem when we have a slight mis-registration on the press, the result is a colored halo around the type. We recomend that the type be converted to just black. If at all possible the conversion to black only type should be corrected in the native application. However, if this is not possible use the following steps from Acrobat 8.0.
  1. Open the file in Acrobat.
  2. Utilizing the Touch Up Tool Circled in red.
  3. Right or control click on the picture that you want to fix.
  4. Select the "Edit Image function". The image will open in Photoshop.
  5. Using the marque tool draw a marque around the black type that you want to change.
  6. Notice that type that is eyedropped is made up of all 4 colors.
  7. Now utilizing the adjustments--channel mixer menu. Select Monachrome and move your black slider to 100%.
  8. Now the type that was inside the marque becomes black in the center and some shade of black on the edges.
  9. Save the file and it will be placed right back into the pdf in the same location that it was originally

Friday, December 12, 2008

GDI CUSTOMER GUIDE TO GOOD WEB OFFSET NEWSPAPER PRINTING

GDI CUSTOMER GUIDE TO GOOD WEB OFFSET NEWSPAPER PRINTING ISSUE 1 REVISION 1

We here at Graphic Developments have compiled the following guidelines to assist our most valuable resourse, our customer, in creating the highest quality printed piece. By following these guidelines you can be assured that your printed piece will be reproduced as you anticipate. Taking into consideration the media we print on and the speed at which we print. So please, look these guidelines over and use them as a recipe for good printing.
• All files transmitted to GDI should be in Adobe Portable Document Format (PDF)
• Files should be sent to the size of the media box.
• Files should be sent in the form of PDF 1.3, and must be PDF/X-1a compliant.
Acrobat distiller job setting can be downloaded from our web site
www.graphicdevelopments.com.

Black & White Type
Sans serif type faces are the best choice for newsprint reproduction. Type faces with thin or delicate serifs and strokes, and non-uniform character thickness, should be avoided.
Extremely thin strokes can drop out in the conversion process, while thick strokes can
fill-in on the press. For clarity and readability, we recommend using type sized at least 7 points for black type without a screen.

Screened Type
When using screening type, avoid fine to medium weight type and use sans serif
typefaces. Type should be sized at least 10 points bold.

Reversed Type
To assure quality reproduction use type sized greater than 10 points.

Surprinted Type
When surprinting type over a tint, avoid use of a screen (background) heavier than 30%.

Dot Gain and Blowout
When screening halftones and screens (shades of black), allow for dot gain on the press
(i.e. the dot enlarges on absorbent paper). In the high-light and shadow area, a 5-8% gain occurs and in the midtones a gain of 18-22% occurs. A highlighted dot less than 2% will appear white (blowout) and a shadow dot greater than 95% will appear solid black on
press.
100 Line Screen
Dot area for Black
Image Gain Printed
75% 15% 87%
50% 18% 68%
25% 14% 39%
Any value over 95% will print 100%

Color
Color Ads are designated as either Multi-color (CMYK) or Spot color (also CMYK.).
Spot colors sold and printed in the newspaper industry do not match Pantone color.
Pantone Tru Match System Colors (PMS Colors) are not recognized spot colors in the
newspaper industry. A PMS color is always translated to the CMYK equivalent. That
CMYK equivalent, when printed on newsprint, will not match the PMS color as it
appears in the Pantone swatchbook. Many of the colors found in the Pantone swatchbook
are out of the gamut (printable range of colors) of newspaper production.

Multicolor Ads
A maximum total area coverage of 230% to 240% is recommended with only one solid.
Any secondary colors should not exceed 80% each.
100 line screen ROP 4 / Color Tone Reproduction Guidelines:
Highlight: Cyan-4% Magenta-2% Yellow-2% Black-0%
Shadow: Cyan-60% Magenta-50% Yellow-50% Black-80%
Gamut: The range of tones or colors that can be produced by a system or device.
Michael Kieran, "The Color Scanning Success Handbook" (1997) *estimated
The human eye is capable of detecting a very wide range of color. In fact, its color range or gamut is far greater than that of a color scanner, printer or printing press. This difference makes color scanning and printing very challenging.

Images
Scanning Resolution: 254 pixels per inch at 100% of final output size.
Gray Component Replacement (GCR)
GDI recommends Gray Component Replacement (GCR). "The theory behind GCR is that
whenever cyan, magenta, and yellow are present in a color, that color must have a gray
component. With GCR, some or all of this gray component is printed with black ink,
thereby reducing the amounts of colored inks required." Reduction of ink limits rub-off
and color saturation. "GCR also helps solve a major problem in color printing: producing consistently neutral grays. In traditional process color reproductions, neutral grays are created by delicately balancing the three process inks. A slight variation in the amount of any of them can result in visible color shifts. Printing with GCR separations removes this problem, allowing neutral grays to stay neutral because they are made primarily with black ink. Another advantage of GCR is that it reduces the effects of variations on press,so when ink coverage varies, the colors become slightly lighter or darker rather than changing hue. "If you’re creating color separations in Adobe Photoshop, set the black generation in the Separations Setup dialog box to Medium; the None setting for GCR has no practical value, and the Maximum setting can be dangerous because any neutral color will appear grainier than the rest of the picture." For further information see The Color Scanning Success Handbook by Michael Kieran.

Spot Color
Spot Color Ads (are not really spot)
Spot colors in the newspaper industry are pre-defined CMYK colors to be used in
addition to black. Spot color ads are positioned and treated differently from multi-color ads. The Spot colors listed below are the only predefined spots colors available.

Spot Color Image
All spot color ads should be prepared as CMYK composite files.
DO NOT prepare separations for spot color ads in newsprint.
Color images must be CMYK, including duotone images.
When creating an ad to be printed as spot color, there must not be any information on the unused plate (or channel in Photoshop.) Example: A spot color ad using #75 RED (m100 y60) should not have any information on the cyan plate. Any supporting files such as a Photoshop image or an Illustrator EPS must follow the same rule. All color elements in a spot color ad must be prepared with the specified CMYK mix or a tint of that CMYK mix.

Pantone Colors
Pantone Tru Match System Colors (PMS Colors) are not recognized spot colors in the
newspaper industry. A PMS color is always translated to the CMYK equivalent. That
CMYK equivalent when printed on newsprint will not match the PMS color as it appears
in the Pantone swatchbook. Many of the colors found in the Pantone swatchbook are out
of the gamut (printable range of colors) of newspaper production.

Other Things to Avoid
Rich black Black =100 Cyan =30 Magenta =30 Yellow = 30
Any Ad entry that’s in RGB (red green blue) or Lab color space.
Knock out text set to overprint. Depending on your Acrobat preferences knock out text
set to overprint may display properly, but will print overprinting the background, Ink is not opaque so when one color over prints another the two colors combine (i.e. yellow
type on blue background will come out purple)or in the case or white text, the type will disappear.