The photographic and topographic materials on this website were acquired from the MSTS/USGS databank in 5-by-5 arrays of 25 tiles using custom-built HTML codes. Each USGS tile is a small 200pixel-by-200pixel graphic. The tiles were acquired at the highest resolution USGS makes available for each type of materal: 1-meter resolution for photographic tiles and 2-meter resolution for topographic tiles. At the 1-meter resolution each pixel represents one meter, while at the 2-meter resolution each pixel represents two meters. The horizontal and vertical boundaries of each USGS tile lie on horizontal and vertical metric grid lines of the NAD83UTM grid having UTM coordinates which are integer multiples of the tile size (either 200 meters or 400 meters). Using the grid/snap feature of Adobe Photoshop 6.0, these 5-by-5 arrays of small USGS tiles have been coalesced into large JTNP tiles portraying 1-kilometer-square areas for the aerial photographs at 1-meter resolution or 2-kilometer-square areas for the topographic maps at 2-meter resolution. The JTNP topo tiles were then doubled in size so that they would match the scale of the JTNP foto tiles on the computer screen. The horizontal and vertical boundaries of a JTNP tile lie on horizontal and vertical metric grid lines of the NAD83UTM grid having UTM coordinates which are integer multiples of the tile size (1 kilometer for the foto tiles and 2 kilometers for the topo tiles). The name assigned to each JTNP tile on this website is the UTM coordinate-pair of its SW corner, with the three least-significant zero digits omitted from each coordinate.

To provide website visitors a convenient way to download the foto and topo materials in an organized manner, the JTNP foto tiles are organized by HTML codes into 2-by-2 ARRAYS while the JTNP topo tiles are organized by HTML codes into 1-by-1 ARRAYS. In each case, an ARRAY portrays a 2-kilometer-square area whose horizontal and vertical boundaries lie on horizontal and vertical metric grid lines of the NAD83UTM grid having UTM coordinates which are integer multiples of the ARRAY size (2 kilometers). The name assigned to each such downloadable ARRAY is the UTM coordinate-pair of its SW corner, with the three least-significant zero digits omitted from each coordinate. The ARRAYS of JTNP tiles are further organized into 5-by-5 arrays called AREAS each covering a 10-kilometer-square area. The horizontal and vertical boundaries of an AREA lie on horizontal and vertical metric grid lines of the NAD83UTM GRID having UTM coordinates which are integer multiples of the AREA size (10 kilometers). The name assigned to an AREA is the UTM coordinate-pair of its SW corner, with the four least-significant zero digits omitted from each coordinate.

At the one meter level of resolution, MSTS/USGS makes available only aerial photographs, not topographic maps. At the two meter level of resolution (as well as 4-meter, 8-meter, etc.) MSTS/USGS makes available both aerial photographs and topographic maps. The topographic maps are carefully mated USGS 7.5 minute quads at the two meter level of resolution (as is the case also with the excellent National Geographic Seamless Shaded Relief USGS Topographic Maps on CD-ROM ).

MSTS makes available only 2-by-1, 3-by-2, and 4-by-3 USGS tile arrays, together with a "click-to-move" feature which allows movement from a current array to any of eight (slightly overlapping) adjacent arrays. Downloading MSTS arrays is slow, but revisiting an array is hastened by the "Temporary Internet Files" feature of Internet Explorer provided one does not overload that feature. But all the material may be lost upon closure of the Explorer window.

Construction of this website was begun in Spring 2000 in order to permit the dedicated enthusiast of JTNP to accumulate in a personal computer LARGE views of JTNP which can be viewed rapidly on demand, in order to be able to locate hiking targets such as climbing rocks and trails and to be able to follow access routes to those target locations by scrolling within single LARGE views. Within the downloadable ARRAYS, and in the larger displays whose HTML codes are under construction, a slowly growing set of the names provided for climbing rocks in the excellent  Joshua Tree: Rock Climbing Guide by Randy Vogel  are being made visible when the cursor is placed over the rocks, much in the manner already long provided in the  Preview of the Types of Graphics Available on this Website, in order to assist the website visitor in locating rocks of interest.

NOTICE: Successful viewing of the material provided by this website requires CONSIDERABLE DEDICATED CAREFUL EFFORT. The basic unit of photographic or topographic USGS material provided by this website is the 2-kilometer-square ARRAY of JTNP tiles, which may take over a minute to download, so that casual viewing will quickly be found unrewarding. Instead, the viewer is encouraged to construct a directory hierarchy according to the directions given below, and then to download desired portions of the material into that hierarchy as directed below. Once desired materials have been downloaded to the local site, viewing rapidly on demand will be found easy and quite rewarding. For example, the Boy Scout Trail can be followed at 1-meter resolution from beginning to end in a single LARGE display once the requisite materials have been downloaded. While the 2-kilometer-square ARRAYS of JTNP tiles are themselves quite large compared to the small arrays available from MSTS/USGS, this website makes available a few very much larger arrays as well.

First, establish a directory named publ_html on your computer desktop or elsewhere as you wish. (I am using the "non-standard" name publ_html for the directory in the local computer to help distinguish the local environment of your computer from this website environment, where the "standard" name public_html is required.) Then form additional directories in accordance with the following table, which is an exact reflection of a portion of the directory structure you will find in this website. The AREA directories then lie within the foto and topo directories, the individual 2-by-2 ARRAYS of JTNP tiles lie within the AREA directories along with the individual JTNP tiles themselves, and the individual USGS tiles from which the JTNP tiles were colasced lie within subdirectories of the AREA directories. Finally, the HTML codes for the few very much larger arrays lie within the foto and topo directories so that they can access JTNP tiles within multiple AREAS. The major very much larger array is wonderland.doc which displays essentially the whole of the Wonderland of Rocks when downloaded and converted to wonderland.htm as prescribed at the bottom of this page. Many of the entries in the website environment below are links on which the user may click in order to observe what is available.

The viewer will discover the following two properties of a 10-by-10 array of tiles when viewing the array, either as freshly acquired from this website or later within the local environment.

PROPERTY 1. When the cursor is left stationary within the array, a small popup window displays for a few seconds the UTM coordinates of the hectare within which the cursor is positioned.

PROPERTY 2. When the cursor is left stationary in a small region near any one of the four corners of the (source) array, a small popup window displays for a few seconds a message Click to move .. from that corner of the source array to the closest corner of the adjacent target array in one of the only three directions possible from that corner of the source array.

The Wonderland of Rocks display is present as the file wonderland.doc within the public_html/jtnp/usgs/foto/ directory. To acquire this file, click on the link in the preceding sentence to obtain the directory listing, click on the wonderland.doc directory entry to open the file, and then save the file into the publ_html/jtnp/usgs/foto/ directory within your local environment with the extension .htm. Opening this file requires a few minutes even in the local environment, but the effort to acquire and open this file is richly rewarding - the entire Wonderland of Rocks is visible in a single picture (with scrolling), and the Indian Cove Trail can be followed all the way from the Willow Hole Trail past the west end of the Indian Cove Campground to the Indian Cove Road. Even the most steeply descending portion of the trail, north of Keys Hill and very faint, can be followed at the 1-meter resolution. WARNING: This file is about 900-kilobytes in size.

Experience has shown me that attempting to view a VERY LARGE ARRAY (essentially anything over about 100 tiles) directly from the WEBSITE ENVIRONMENT is doomed to be a futile effort.