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When Your Files Leave Home

Are you are successful in building files on your own system but run into problems when it comes to taking a file out for printing or giving it to a co-worker? The best solution is to design around potential problems by anticipating the probable uses of the file.

Most text files these days can easily be converted from one file type to another. Problems with text files usually involve fonts. Be sure you choose a font present on both systems. If the font is not present on the other system, perhaps you can install it long enough to print (giving out copies of your fonts may break copyright laws). Or perhaps you can just change fonts — using styles in programs with this feature (Microsoft Word, Adobe-Aldus PageMaker etc.) makes changing fonts relatively easy. Windows fonts are not installable on Macs and vice versa. Also keep in mind that some True Type fonts may not print to Lino — check with your service bureau. If you are using a special font in just a few places, perhaps you can make it a graphic (see converting to curves with vectored graphics below). If you know you have the printer font and not just the screen font, you can make a PostScript dump file which will include the font and all the file information. Be careful to select the new printer and check all the correct boxes because neither you nor the service bureau can make changes to a PostScript dump file.

With bit-mapped graphics (scanned or paint type) the main problems are in resolution and file size. High resolution means a large file and long processing times. Low resolution gives you a smaller file but it may be jagged in final output. The general rule of thumb is that the image resolution for continuous tone (photos, not line art) at final size should be twice the line screen of the final output. We usually recommend compressed TIF as file type because it transfers across platforms easily and most color separation programs can deal with it. Some example line screens and file sizes: Device for For printing Scan at Approx. file size of Final Lines Per Inch Dots Per Inch 3x5" grayscale photo Reproduction (lpi) (DPI) 4 Color is 4x larger 300 dpi laser printer 54 108 171K standard photocopier 80 160 375K 600 dpi laser printer or newsprint 85 170 424K quick print, (paper plates) 100 200 528K inside most magazines 133 266 1.01Mb some magazine covers 150 300 1.29Mb fine art printing 200 400 2.29Mb

Device for
Final
Reproduction
Line Screen (lpi,
Lines per inch)
Gray scaleScan
at (dpi,
Dots per inch)
Approx. TIF File size of
3x5 photo (gray scale,
color is 4x larger)
Scan Black
and White
Line art at (dpi)
computer screen 72 to 100 (not TIF) 72 to 100
300 dpi Laser 54 108 171K 300
standard photocopy 80 160 375K 600
600 dpi laser
newsprint
85 170 424K 600
quick print 100 to 120
Ask them!
200 to 220
Ask them!
528K 600 for matte paper
1270 to film for glossy
Ask them!
inside of most magazines 133 Ask them! 266 Ask them! 1.01M Ask them!
some magazine covers 150 Ask them! 300 Ask them! 1.29M Ask them!
fine art printing 200 Ask them! 400 Ask them! 2.29M Ask them!

To transport large files use file compression (PKZIP on the PC, Stuffit on the Mac or compressed TIF on either), multiple disks (Backup or recent PKZIP on the PC, Stuffit on the Mac) or large storage devices (Syquest, Bernoulli, optical, tape, writable CD etc.). Be sure the destination for your file can deal with your method of moving it. Some service bureaus scan your image in two resolutions and keep the larger file for you.

Vectored images, unless you have incorporated a scanned file, do not have these resolution problems and generally have small file sizes. Trace programs, such as Adobe Streamline or Corel Trace, convert scanned line art from bit-mapped to vectored image so that you can get away from bit-map problems. The vector file type can cause a lot of headaches. EPS (encapsulated PostScript) crosses platforms most easily but you generally need to print to a PostScript printer. For Mac users this isn’t usually a problem. PC users can use WMF (Windows Metafiles) for non-PostScript Windows printers but this format does not directly transfer to the Mac environment. Likewise, the Mac Pict format doesn’t transfer directly to the PC but works well within the Mac environment. Even with EPS, there can be problems since the format is not as standardized as it started out. File types can usually be converted from one to another to solve problems.

Vectored graphics, unlike bit-maps, have the same font problems as text files. However, most draw-type software has a built-in fix called converting to paths or curves. Once this is done the text is editable as a graphic but not as text any longer. The file needs no font information to print. Be sure you do this to every text block. We usually have two versions of a file: one for editing and one with text changed to curves, for exporting. Give us a call at 206-523-0872 if you need help or have further questions.

copyright 1998 Karen Seymour

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