Scale and--

[Silverleaf]

Hiya Alex,

I'm sure others will chime in with better information but one way to look at the scale on a map is the relationship between the distance on the map and the distance on the ground. Usually, the relationship is expressed as a fraction e.g. 1/10 000 or a ratio e.g.1:10 000. In plain English this means that 1 unit on the map represents 10,000 of the same unit on the ground.

The unit of measurement is commonly inches (or centimeters). The first number in the scale is always 1, but the second number is different for each scale. Some commonly used scales are:

* 1:24,000 - 1 inch on the map equals 24000 inches in the real world, which is the same as 2,000 feet.
* 1:63,360 - 1 inch equals 1 mile
* 1:50,000
* 1:250,000
* 1:1,000,000

Lastly, when choosing a scale, remember, "bigger is smaller." The bigger the second number, the smaller the scale of the map. More ground is represented on the map, and therefore there is less detail on the map. Conversely, the smaller the second number, the bigger the scale, and more detail can be included on the map.

More info

Compass Dude

*****
As to "creating a map in Photoshop CS5 from another medium, like paper or a picture". You have a couple options:

Scan the plain paper map in with a scanner, save it as a png (pngs have good transparency support), then open up in CS5 and do your work. If a photo that's available on a flash drive/cd-rom/dvd, pull it onto the computer, open it in CS5 and do the same work. Otherwise, scan it in with the Twain feature (from your scanner), and voila!

Hope that helps,