Transcript data source

A. GENERALIZATION
Generalization – how to decide?
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Scale of the map may dictate your needs
May seem arbitrary at times, although it helps to
simplify for easier viewing sometimes
Also, well-defined points can be important
Why?
Generalization: Standards
See: http://erg.usgs.gov/isb/pubs/factsheets/fs17199.html
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National Map Accuracy Standards (est 1941)
At scales of 1:20,000 or smaller, the map must be
checked for symbols that deviate more than 1/50”
(0.02 centimeters) on the map.
– 90% of checked points must comply.
– Points include: large building corners, survey
markers, major rail, road intersections.
– e.g. At 1:24,000, this is roughly 12 m deviation, or 40
ft
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Generalization – methods
Generalization – methods
B. MAP COMPONENTS
neatlines, framelines
legends
north arrow (orientation)
titles & subtitles
scale
data source
insets
1.Frameline & Neatline Separated
Neatline
Frameline
The frameline should
include all map elements
that viewers will need to
understand the map.
The neat line is used
to define cropped
regions of the map.
The map elements
need not be included
within it.
3. Frameline acts as neatline
2.Frameline
LEGENDS
Keep legends clean and simple.
Verify that important features are
represented correctly in your legend in
terms of color and apperance
Legends do not require and outline box,
but sometimes they may improve
appearance and/or clarity
Legend headings help to understand the
map's theme and purpose and units if app.
LEGENDS: Creating, Customizing
ArcMap – limited in scope, but
adequate for most maps
(customized legends possible)
More customized
style; drawn in art
program
LEGENDS: Symbols/Symbology
Abstract Symbols – vary shape, size, color to highlight
features and discern them (e.g. dots, squares)
Representative Symbols that “look” like what the represent –
e.g. flames for fire, dollar signs for banks
Symbols by convention – water is usually blue, dots are
often cities
Symbology will be covered again when we work on thematic
maps starting next week. Read ahead 196-226 if you are
curious (Krygier & Wood, 2005)
TITLES and SUBTITLES
Titles should be included on the map. Make them
succinct
Subtitles may include details such as years, one-word
descriptions of data, locations
The title should be the largest type on the map
Avoid fancy and ornate type styles. Also avoid italics.
Bold type is ok.
Masking may be used if needed
TITLE MASKED
TITLE NOT MASKED
ORIENTATION - refers to the
indication of direction on a map
1. May be depicted using a graticule (the
'grid' of latitude and longitudinal lines).
Discussion of the graticule will be next week.
2. May be depicted using a north arrow
NORTH ARROW
ArcMap has several
available north arrows
By convention:
Use the most simple north
arrow if you just need to
orient the map viewer
ESRI North 2 is best
Use the compound arrows
for navigational maps and
charts
SCALE BARS
Scale on a map :
1. gives th amount of reduction that has taken
place in the map
OR
2. allows users to measure distances on a map
As a visual element, it is represented as a
scale bar (also bar scale).
Use it if distance is important to the viewer's
understanding of the map.
SCALE BARS
As with North Arrows,
avoid complex scale
bars. Stick to the most
simple ones.
Here, Scale Line 1, 2
or 3 are adequate.
* Use round numbers, easy to double,
triple for scale bar length (e.g. 200 miles)
More on scale use next week!
Deciding divisions
depends on the map's
intended use. Are
estimates, or near
exact distances
needed?
INSETS
Smaller maps included
within a context of a
larger map
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Locator inset
Ease congestion by
enlarging
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Depict changes,
themes over time
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Inset styles may vary. There is no set convention.
Suggestions: use neat lines, framelines and visual
connectors to strengthen relationships
DATA SOURCE
From where did your data come (e.g. dollars
spent, houses sold, etc)??
Use plain, subtle text for this element
Use this format:
Source: California Department of Labor, State Housing Data
Bank, April 1, 2000
Place it at the bottom of your map. It should be
inconspicuous, but locatable.
C. TEXT USAGE
Nomenclature - Type
Type family – group of similar designs
Type style – Roman, Bold or Italic (others exist
such as condensed, expanded, light, extra bold
Typeface – type of a specific family & style
Type size – the “size” (height) of the type given in
points (1 point = 1/72”)
So what is a font?
A font is the set of all alphanumeric and special
characters of a specific type family, type style and
type size.
General rules - type on maps
Use the same type throughout the map. .
Stay consistent. Exception: label water
with Times New Roman in italics
Avoid decorative type unless it is an
especially unusual or decorative map.
This is unlikely in professional
envrionments.
Do not make type too small.
Type size should correspond to feature
size.
Do not blindly accept defaults in ArcMap,
or in Ilustrator for that matter.
Spell-check!
General rules - type on maps
Point features
1. avoid overprinting (covering graphic objects)
2. avoid separation between features and labels by other
features
3. use sequence of preferred locations for labeling point
features
4. align type if more than one line involved (alignment)
5. label points that lie close to coasts (but are on land) on the
land
6. label points that lie ON the coast entirely in water, or
entirely on land
th
3rd best
4th best
best
2nd best
5
best
6th
best
General rules - type on maps
Linear features:
1. Keep descenders (“g”, “y”) above the path. Keep type
above the path, except for borders that require labeling
on both sides of the feature
2. Follow the general trend if you have very curvy linear
features
3. Use repetition instead of spreading text out
4. Place text upright and readable from left to right
5. If you are placing text vertically, make sure that it can
be read from the right side of the page rather than the
left (test by focusing your eyes toward the right side of
the page and verifying that you can read it.
General rules - type on maps
Areal Features
1. Use tracking to separate text in areal features. Also, try to
use separation of AT LEAST 1.5 em's (tracking unit) between
last letter and border of areal feature.
2. Consider using all uppercase lettering
3. For more than one line, exaggerate leading to cover area
4. If an areal feature is too small to place text within it, label it
as a point .
5. If a line feature is thick and nearly areal (e.g. a canal),
label as an area, following the general trend of the feature.