The NPS uses Adobe Illustrator and Adobe Photoshop
software to create visitor use maps.
Adobe Illustrator Maps
Adobe Illustrator maps, symbol files, and patterns are provided
in Illustrator versions 6.0, 8.0, 10.0 or 11.0 (Illustrator CS),
depending on the date of production. All Illustrator map files are
both WindowsPC and MacOS compatible. All earlier Illustrator formats
are readable by more recent versions of Illustrator. Forward compatibility
is far more restrictive: opening version 10.0 or 11.0 files requires
Illustrator 10.0 or 11.0, respectively.
Data Compression
Depending on their creation date, the Adobe Illustrator maps on
this site use two types of file compression. Prior to 2004 and the
switch to standard .zip compression, all Illustrator maps used proprietary
Stuffit compression indicated by a .sea (self-extracting archive)
suffix. Use Aladdin Stuffit Expander freeware to decompress .sea
files (Help
with Aladdin Stuffit). Most lllustrator maps occupy less than
1 MB, although some are as large as 18 MB when decompressed.
Layers
In Adobe Illustrator, layers organize the various classes of map
information. A typical NPS map contains 20 to 40 data layers, although
one exceptionally large map contains 150 layers. You will see specifications
about individual layers when the layers palette is open. Most maps
contain a "junk" or "does not print" layer at
the bottom of the layers palette where you will find additional
data and pieces of linework removed from the printed map. Carefully
inspect the contents of "junk" layers before discarding
because some of the information on these layers may be useful.
Overprints & Trapping
The construction of NPS maps ensures that type, lines, area fills,
and symbols overprint correctly on an offset press. Be very careful
about moving or modifying trapped objects, especially red roads.
Changes to these elements may invalidate the trapping and cause
unsightly display problems.
Fonts
National Park Service maps made prior to 2001 use Adobe Helvetica
Neue fonts, sets 1, 2, and 3. Maps made after 2001 use Adobe Frutiger,
the new NPS type standard. To exactly match the type positioning
of original maps, users need to purchase the Helvetica Neue or Frutiger
fonts from Adobe Systems. Substituted fonts may position incorrectly,
especially in congested areas. Adobe
Systems »
The National Park Service uses a proprietary font for labeling
Hawaiian names that contain diacritical marks. The font is not released
publicly. Due to font substitution, diacritical marks do not appear
on downloaded maps. Check printed National Park Service maps for
the correct spelling of all Hawaiian place names.
Shaded Relief
The shaded relief is in JPEG format to hasten the download time
of these large files. Originally the shaded relief was in Adobe
Photoshop EPS (older maps) or Photoshop (new maps) format (grayscale,
200 dpi) and converted to JPEG at the highest quality setting.
Registration with Illustrator Linework
To automatically register shaded relief to line work in the Adobe
Illustrator do the following:
- Download the Adobe Illustrator map file and JPEG shaded relief
for a specific map.
- Open the JPEG shaded relief in Adobe Photoshop or a similar
paint program. Save the shaded relief in either EPS or Photoshop
format, depending on the age of the map.
- Decompress the Adobe Illustrator map file and open. When Illustrator
launches, a dialog asks you to locate the shaded relief file.
Specify the EPS or Photoshop file you just saved. When the Illustrator
map is fully opened the shaded relief will appear in correct registration.
Hint: The shaded relief layer may be obscured by overprinting
fill colors; turn these layers off to view the shaded relief.
- Save the file. The shaded relief will now appear in correct
position every time the Illustrator map is re-opened.
Resolution & Density
The resolution of shaded relief art at final size is 200 dpi, intended
for printing with 175 lpi screens. Our testing has shown that higher
resolution adds no additional relief detail, but only increases
files to unwieldy sizes.
Most NPS shaded relief art displays a density range from 4 to 65
percent black. You can modify these values easily in a program like
Photoshop. The typical density range for black shaded relief in
a National Park Service map is: highlights 0-2 percent, flat areas
3-5 percent, and shadows 15-18 percent.
Note: Shaded relief tones below two percent density
often disappear when printing with 150 lpi or higher screens.
Learn more about the presentation of relief on maps: Ideas
& Techniques about Relief Maps »
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