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. 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 »
Last updated: November 10, 2022