30 September 2007

Here is the first cycle of maps related to the Greater Goulding Creek Watershed. I have found most of these useful but have not yet listed them in a Subject Page. I plan to have all the maps listed on this page, regardless if they also come to be listed on a Subject Page. Some will be great as is, some useful only if reworked or incorporated elsewhere, and some will just be awful but you never know who might need it.

There will be more versions of a particular map than you want to download. I will try to provide the original, or at least a link to it, usually in a pdf or jpg format. Then its first conversion to a working format, usually png, but before I have messed with it. Then drafts and finished products in various formats that are best for particular uses, such as pdf for printing, png for more image processing, and jpg for web and printing. If you are interested in your own modifications or in moving its information onto another image, work with a version as close as possible to the original.

The code tries to both identify the parental map and the history of manipulations leading to the particular version of the parental map. The first number specifies a Subject Page and the second number a unique map or document. Subsequent numbers trace the history of the various modifications or format changes made to the original version of the map or document. This will probably turn out to be too confusing or just too complicated, but I will give it a try. Although it is not my intent, do not be surprised if a particular map has different numbers on different Subject Pages.

What follows is a very brief summary of what I think is the most important use or advantage of each format. If you want to print a map, or various portions of it, choose a pdf format if it has sufficient resolution. If you want to modify the map, move some of it to another image, distort it, add to it, or otherwise mess with it, choose the png format and immediately reduce the size of its file to one sufficient for your needs and your machine.

pdf and jpg are the favored formats for large-format printing at commercial copying and printing services. Most claim they cannot print a png image. They can but it is a lot easier giving them a pdf they know how to handle.

If creating a jpg format from a pdf or png, specify the lowest compression/highest quality. If creating a pdf, specify the highest quality and a paper size about the size of the actual image. You can still make a hardcopy at any size, but the quality of the pdf is best when it is close to actual size.

When viewed in Adobe Reader or Acrobat, it is easy to print exactly the portion of a pdf page that is displayed on the monitor. It is more difficult to print just portions of an image, regardless of its jpg, png, or gif format. If using a printing service, provide a hardcopy of the entire document marked with those areas you wish printed with notations as to percent scale appropriate for each image.

Retain the png format if you are going to do any processing or repeated saving of the file. The parental files take up to 0.5 Gb of memory when opened in Paint Shop Pro or Adobe Photoshop, but they can be modified and saved without loss of resolution. Get as much physical memory as possible and increase virtual memory into the 5-30 Gb range. Use other tricks to keep the file size small and processing times short: Crop to the working area, resize to just above the resolution you think you need at the end, and reduce color depth. Some operations require high-depth color to get them started, such as choosing a new color, but once done the depth can be again reduced for the actual operation.

Enjoy and I hope some of these are helpful. There are a lot more to be added.

Glenn Galau