Q. What are the ArcGIS Server URLs used to connect to the CT ECO map and image services?

A. There are two ArcGIS Server URLs to use, depending on the type of data you need to connect to.

• Use https://cteco.uconn.edu/ctmaps/rest/services to connect to thematic map services.
• Use https://cteco.uconn.edu/ctraster/rest/services to connect to imagery and elevation.

For services available from CT DEEP and other places, visit the CT Geodata Portal, part of the CT GIS Office.

Q. What type of orthophotography is available for Connecticut from CT ECO?

A. More than 15 datasets of orthophotography are available on CT ECO. There are many variables that make each dataset unique including:

• year captured
• different seasons (spring or summer)
• different bands (black and white, true color, false color) and
• different pixel resolutions (such as 1 meter, 1 foot and 0.25 foot)

Photography taken during the summer is generally referred to as "leaf on" orthophotography, and photography taken during the early spring is generally referred to as "leaf off" photography. Leaf off is captured immediately after the snow cover melts and before stream levels rise and leaves blossom on the trees. It is ideal for observing features on the ground surface in developed, open or wooded areas. The leaves on trees and shrubs that would normally obstruct the view from above during the summer are largely absent in the early spring, allowing for the observation of features such as stone walls, roads, and structures in wooded areas, lawns and yards.

Refer to CT Digital Aerial Datasets for a list and brief description of orthophotography available from CT ECO.

Q. How do I connect to the services?

A. Visit the page that best suits your method -

Connect to the CT ECO map or image services in ArcMap

Connect to the CT ECO map and image services in ArcGIS Online

Connect to the CT ECO map and image services in ArcPro

Connect to the CT ECO map and image services in Google Earth.

Connect using WMS

Q. What is a tiled or cached service? Advantages and disadvantages over a dynamic service?

A. A tiled or cached map or image service is a when a dynamic service has a pre-created cache which consists of many, many pre-made "pictures" of the service. The result is faster access for users as no processing is being performed on the server.

The opposite is dynamic map and image services have built-in capabilities where the user can change some of the layers behavior and appearance. For map services, symbology and other features are available. For image services, the user can change display, bands, stretches and more.

Q. If an image service has tiles, how can I use it as a dynamic image service in ArcMap?

A. View a tiled service as dynamic.  A cached image service can be accessed using the cache for quick display or this ca be disabled to provide dynamic access to all the image service capabilities.

After adding the cached or tiled service to ArcMap, right-click over the layer and uncheck Enable Cache View Mode.

Q. Are the CT ECO map services available in Web Map Service (WMS) format?

A. Yes. Many GIS softwares can connect to the WMS version of the CT ECO map and image services. There are two ways to find the WMS address. The easiest way is to use the REST endpoints. Follow these instructions. The other way is to build the URL. Read how here.

1. Visit the ArcGIS Server REST endpoint page (here for vector services REST, here for image services REST)

2. Navigate the folders and locate the desired service

3. Find the WMS link in the upper left-hand corner

4. The WMS link opens an xml file that contains the full link to the WMS service. Copy the link and use it in the GIS software.

Some services also list WMTS which is a Web Map Tile Service. It behaves similar to WMS but accommodates tiled services.