Updated
11/21/11
File
Formats
PS
EPS
TIFF
PICT
JPEG
GIF
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Inside
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> BaRC >
Graphics > File Formats
Understanding
File Formats
You
can avoid distorted images and printing errors by knowing which format
works best for different types of files. The best format to use is always
the format native to the application you are using. You should save and
edit your files in this format (in Canvas, save as Canvas format (.cvs),
or in Photoshop, use Photoshop format (.psd).)
However,
in transfering a file from one application to another or for interpretation
by a film recorder or certain printers, using a more universal format
is often necessary. It is important to become familiar with the differences
between these formats so that you can decide when to use each to get the
highest quality output.
FORMAT |
DESCRIPTION |
Save
in this format if the file is native to: |
PS
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to top |
PS
(PostScript, .ps)
is the language of printers. When you hit the print button, on the
way there the file is translated into the PostScript language. |
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EPS
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EPS
(encapsulated PostScript, .eps)
is a PostScript file with a preview attached, so you can place it
in a graphics application and see what youve got. The part of
the file that goes to the printer is PostScript, and so is very accurate.
Most software applications can open EPS files, but the preview quality
varies between them. Some applications offer only very low res. EPS
previews, so on screen they look blocky, even though they print at
a high resolution. |
Illustrator
FreeHand
Canvas
(any
vector drawing program) |
TIFF
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|
TIFF
(Tagged Image File Format, .tif)
This is a bitmap format, which is a good choice for files created
in Photoshop. The advantage of this format is that many other software
applications can open it, and there is no loss of quality between
PSD (Photoshop format) and TIFF. However, TIFF does not support layers,
and files saved at TIFF from Photoshop 6 will automatically be flattened.
If you want to keep layers, save a copy and keep your original PSD
file. |
Photoshop |
PICT
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|
PICT(.pct)
format is good at compressing images with large areas of solid color,
such as graphics made in Illustrator, FreeHand and Canvas. It usually
makes vector images into bitmap images, although PICT 2 retains
some vector information. Because it is a compression format, you
will notice some loss of quality which will dramatically increase
if you try to scale the image after saving as PICT. You also wont
be able to edit vector work after the conversion, but you can open
it in Photoshop to make some kinds of color adjustments, etc.
Cross-platform
Issues: PCs cannot open Mac PICT files. This is an issue for cross-platform
work and should be considered when making PowerPoint presentations. |
PowerPoint
to film recorder.
Canvas,
FreeHand, ClarisDraw, Illustrator to PowerPoint (but not for cross-platform
use)
Not
recommended for printed output. |
JPEG
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JPEG
(Joint Photographic Experts Group, .jpg)
format is used to compress files for web display. You can choose the
amount of compression used to find the right balance between file
size and image quality. Files should be saved as JPEG format only
once, since each time the file is saved it is compressed further.
This is called "lossy compression". This is why it is essential
to keep a copy of your original PSD file, so you can always go back
to that if you need to make changes or if you need the high-quality
version of the file. JPEG works best for screen display and should
not usually be used for print as it tends to look fuzzy. |
Photoshop
(for web display or PowerPoint only) |
GIF
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GIF
(Graphics Interchange Format, .gif)
is another compression format often used to prepare images for the
web. GIF is best used on vector information (hard edged graphics made
in Illustrator, FreeHand or Canvas) or text. It produces crisper lines
than JPEG, but has limited color capability so it isn't ideal for
photographs or keeping colors accurate. When saving in GIF format,
use the "adaptive" palette option to get the most out of
the limited color options. You can choose how many colors to use in
a trade-off between color accuracy and file size. |
Canva, FreeHand, ClarisDraw, Illustrator (for web display or PowerPoint only) |
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