Connecticut Elevation Viewer Help and Tips


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Moving Around the Map | Layers | Coordinates | Click on the Map for Pop-up Information | Boundaries and Footprints| Swipe


Moving Around the Map


Zoom in and out of the map using the + and - tools located in the upper left hand part of the map.

To move around the map, click on the map and hold the left mouse button while dragging, then release the left mouse button. This pans the map to different areas, but does not change the zoom.

Home iconIf you get "lost" on your map, use the home button to go back to the initial extent, which is the state of Connecticut.



Layers IconViewer Layer ListThe layer list button in the upper right is one of the most useful buttons on the map. Click on it to see all the layers that, together, make up the map. The layers form a stack (bottom of the list draws on the bottom of the stack) and can be turned on and off. A check mark means the layer is turned "on" or visible (as long as no other layer higher on the list is turned on and is hiding it from view). In the graphic below, notice that CT Towns is turned on (checked) along with the Hillshade layer. If you turned on Slope and did not turn off (un check) Hillshade, the slope would draw but not be visible because it would be hidden under the Hillshade layer.

The little arrow to the right of each layer hides some useful options including:

Layer Menu

Zoom To - zooms to the extent of that layer.

Transparency - makes the layer see-through. It is a sliding scale from 0% (nothing showing through) to 100% (layer is completely transparent and therefore not visible). The illustration below shows a case where the hillshade is 0%, 25%, 50%, 75% and 100% transparent. An aerial image service is underneath the hillshade and shows through as the transparency increases.

Transparency 0% Transparency 25% Transparency 50% Transparency 75% Transparency 100%

Move Up and Move Down: Changes the order of the layers (which is also the drawing order).

Description: links to the REST endpoint of that layer. You can read more about REST here, but for Viewer users, this is where you can find some basic (and code-like) information about the layer, such as what server its coming from (look at the URL), the extent settings, attributes, pixel size, etc. Some layers include a detailed description, some do not.



The Viewer displays X,Y coordinates along the bottom. These coordinates are the location of the mouse as you move it over the map or a specific point if you click on the map. Click on the X and Y to change the coordinate system displayed. The two choices are WGS 1984 Web Mercator and NAD 83 Connecticut State Plane Feet.

Map Coordinates Tool Map Coordinates Tool


Click on the Map for Pop-up InformationPop-up

Clicking on the map is another way to get more information about the feature or location that you click on. The information is shown in a pop-up window and is only displayed for layers that are turned on (checked) in the layer list (see Layers above).

If a location is clicked where more than one layer exists and is turned on, multiple pop-ups are present and are revealed in the top blue banner. Notice on the right that it says (1 of 3). This means 3 results were returned at that spot and the first one is visible. To see the next, click on the tiny right arrow in the upper right of the window (circled in red here). The next result is visible - here is it the Hillshade layer showing elevation. Click the little white arrow again for the third result. This is the Aspect layer which displayed aspect in degrees as well as elevation.

For more information on the values returned for each layer, visit slope and aspect on the FAQ page.




Boundaries and FootprintsBoundaries and Footprints

The Layer List contains an item called Footprints. Check on Footprints (click in the small box) to show the boundaries of the different datasets used to create the statewide elevation layer. For more detail or to view one or several boundaries, click on the small gray arrow to the left of Footprints to expand the title. Boundaries and Tiles are visible. Each of these can also be expanded, and individual boundaries and/or footprints can be turned on or off.

Remember, for a layer to draw, ALL checkboxes above it need to be checked (for example, for the Central 2014 Tiles layer to draw, the Tiles must be checked and the Footprints must be checked.


SwipeSwipe Tool

The swipe tool is a nifty way to compare layers in a map. To activate it, click the swipe icon in the lower left corner of the viewer Swipe tool. A slider opens as well as a menu. By default, the swipe will peel away the hillshade and show the imagery, but you can adjust this to compare hillshade and slope, slope and aspect, or anything else. First, be sure the desired layers are checked on in the layer list. Next, use the swipe dialogue to choose the layer to swipe, or peel away. Cool!