Legends, Maps of Count Data, Maps for the Web

 

ArcView

How to save legend categories for future use

·        Open the Legend Editor and create the categories

·        Click the Save button and enter a meaningful file name when prompted, then navigate to your working folder and click okay.

·        To use the saved categories, open the legend editor and click on the Load button; choose the saved file from above.

How to create a map with count data[1], such as population

·        Open the Legend Editor; in the Legend type window, choose Chart

·        Choose a count variable from the Fields window [viz. pop51], then click Add to enter it into the right hand columns showing Symbols and Fields.

·        At the bottom left under Chart Type, select the bar chart icon.

·        Click apply to draw the map

·        To revise the size of the bars, return to the Legend Editor and click on the Properties button; enter values in the window that opens; then return to the editor and apply.

·        To use dots instead of bars to represent the count variable, choose Dot in the Legend Editor instead of Chart.

·        In the density field, enter the count variable, then push the Calculate button.  Check the value in the Dot Legend to see what 1 dot will represent in terms of the variable.  Adjust this value as needed to make a readable map.  [Trial and error]

Photoshop: How to Prepare Maps and Images for inserting into Word or PageMill

Learn to use the on-line Help menu to find answers to questions about the tools and functions of this program.

Steps in creating images/maps with more efficient file sizes that yield the smallest file size with acceptable resolution:

1) open the image; 2) select the desired portion 3) crop 4) compress the image 5) compress further by reducing the resolution of the image (if necessary)

How to select a portion of an image and crop it.

·        On the tool palette, select the rectangular selection tool (top left corner)

·        Click and drag the select tool to surround the part of the image that you wish to keep.

·        Go to the Image menu and then select Crop.  The graphic material outside of the selected rectangle will be deleted.

To change the size of the displayed image, change the value in the small window at the very bottom left of the Photoshop window.

How to save an image in JPEG format and compress it to reduce the size of the file.

·        Under the File menu, choose Save As and select JPG as the type of format.

·        When prompted on the JPEG Image Options window, place the cursor on the triangle under the slide bar; move this “pointer” to the left to compress by degrees. 

·        To see the size of any image, examine the Document size as follows:

On the bar at the bottom of the window, place the cursor on the third frame from the left with an arrow head.  Click and select Document Size

The Document size will be displayed to the left of the arrow head: the number on the left represents the size of the image.

·        Images for the web should have file sizes that are as small as possible without making the image unreadable.  Rules of thumb:

quick loading: 20 kb or less

moderate loading: 20 kb to 75 kb

slow loading: greater than 75 to 100 kb

§         Images for a word-processing document may be somewhat larger, but smaller file sizes are recommended.

How to reduce file size further by reducing the resolution of an image

§         Under the Image menu, select Image Size.  The Pixel Dimensions gives the file size of the image

§         In the Resolution window, reducing the value will yield a smaller image and file size.  72 pixels/per inch is a good choice for images that will appear on the web.  Setting the resolution higher will increase the image size and its file size.  Since the resolution of color monitors is roughly equivalent to 72 pixels/per inch , images intended for screen display or the web need not be of higher resolution than 72 ppi.

 

Page Mill: How to create a basic web page with text, images, and a hypertext link to another page or URL.

(Refer to the handout for brief instructions and the identification of the icons associated with specific functions.)

 

§         Create a folder to hold all of your pages and images.  Use a short folder name in lower case characters WITH NO SPACES, e.g., myproject

§         File/Open a new page

 

§         Set page background in the Inspector.  Let the default be WHITE

 

§         Create a table; highlight a cell; change alignment on the Inspector: vertical alignment and horizontal alignment

 

§         Enter text; use Shift-Enter to start a new line

 

§         Copy and paste text from MS Word

 

§         Preview the page

 

§         Insert a graphic

 

§         Save page with short name without spaces:  firstpage.html

 

§         Open a new page

 

§         Create content

 

§         Create a link between the two pages. Edit/Make Link

 

§         Save

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Robert Schwartz

November 29, 2000


[1] See Monmonnier in the course packet for further discussion of “count” variables as opposed to “intensity” or “ratio” variables such as population density and percentage change in the population due to migration.