The current version contains several corrections. The imagery tiles available for download contain the older version of the metadata file. Please note these corrections.
A correction was made in the Description, Purpose section. The correct information is:
Purpose: Rectified orthoimagery is for public use.
A correction was made in the Data Access Constraints section. The correct information is:
Access constraints: None. This data is in the public domain.
Use constraints: None. Users can copy, modify, distribute and perform work, even for commercial purposes, without requesting permission.
A correction as in the Metadata, Metadata Access Contraints section. The correct information is:
Access constraints: None. This data is in the public domain.
Use constraints: None. Users can copy, modify, distribute and perform work, even for commercial purposes, all without requesting permission.
To download the corrected xml, click here to open it in a web browser. Browsers are all different, but find the place where you can save the page and save the ortho_2016.xml file to your computer.
Please site the imagery as below. The elevation would be similar - just replace the data layer name.
Capitol Region Council of Governments. (2016). 2016 Aerial imagery. Retrieved from http://cteco.uconn.edu/data/flight2016/index.htm.
GeoTIFF | Highest quality image available here but also the largest file size by a lot. |
MrSID Generation 4 | Compressed image file that supports all 4 image bands (blue, green, red, near-infrared) |
MrSID Generation 3 | Compressed image file with the smallest file size because it contains only 3 image bands (blue, green, red) |
TIFF or TIF stand for Tagged Image File Format and is used for storing raster images of all kinds. Geo indicates that the TIF has a word file, called TWF that stores geographic information about the raster file.
MrSID stands for MultiresolutionSeamless Image Database. It is a way of compressing imagery so that it can be quickly viewed. LizardTech pioneered the MrSID technology. With each Generation, LizardTech has improved the functions of the MrSID files. MrSID Generation 3 improved upon Generation 2 by supporting unlimited files sizes, lossless encoding with optimization and manipulation options. MrSID Generation 4 improved upon Generation 3 by supporting multi-spectral and hyper-spectral imagery and an improved mechanism for composite mosaicking. Read the full explanation on the LizardTech website.
DEM - a raster based (pixel) digital elevation model. The tiles available for download are in Tif format.
LAS - is a lidar data exchange file which is a standard format for airborne lidar point data.
Block | Number of Tiles | File size: GeoTIFF | File Size: MrSID Gen 3 | File Size: MrSID Gen 4 | File Size: DEM | File Size: LAS | File Size: Contours |
1 | 3881 | 1.41 TB | 54.2 GB | 72.4 GB | 23.0 GB | 302 GB | 16.9 GB |
2 | 4169 | 1.51 TB | 58.2 GB | 77.7 GB | 25.2 GB | 299 GB | 18.9 GB |
3 | 3239 | 1.15 TB | 45.2 GB | 60.4 GB | 19.8 GB | 239 GB | 16.7 GB |
4 | 3200 | 1.16 TB | 44.7 GB | 59.6 GB | 19.4 GB | 230 GB | 14.1 GB |
5 | 3061 | 1.11 TB | 42.8 GB | 57.0 GB | 18.7 GB | 234 GB | 19.4 GB |
6 | 3617 | 1.31 TB | 50.5 GB | 67.4 GB | 21.0 GB | 317 GB | 16.4 GB |
7 | 2214 | 825 GB | 30.9 GB | 41.2 GB | 13.5 GB | 199 GB | 15.4 GB |
TOTAL | 23,381 | 8.48 TB | 326.5 GB | 435.7 GB | 140.6 GB | 1.82 TB | 117.8 GB |
Town Mosaics |
169 | - | 631 GB | 869 GB |
March 11 - Flying begins for both Lidar and imagery
April 18 - Imagery and Lidar collection completed
March 7 – Tile delivery grid finalized
May - Pilot imagery tiles received by CRCOG
June - QA/QC Firm selected to do independent review
June – Pilot lidar tiles received by CRCOG
November – Decision made to get two types of MrSID (generation 3 and generation 4) to meet needs or all users
December - Imagery tiles for blocks 1, 3, 5, 7 (western half of the state) approved by QA/QC process
December 29 – UConn receives Blocks 1, 3, 5, 7 imagery tiles and begins processing
January – Imagery tiles for blocks 2, 4 (eastern half, south and central) approved by QA/QC process
January 24 – Imagery tiles for blocks 2, 4 (eastern half, south and central) received by UConn
February 10 - all imagery approved by QA/QC process
February 13 - Imagery tiles for block 6, the last one, (northeast) received by UConn
February 22 - dynamic map service and tiled map service completed for the state. All tiles available for download.
March 27 - town mosaics arrive at CLEAR
April 3 - town mosaics available for download
May 22 - lidar DEM metadata and DEM tiles for blocks 3, 5, 7 arrived at CLEAR
May 23 - lidar DEM tiles for blocks 3, 5 and 7 available for download
June 23 - lidar DEM metadata and DEM tiles for blocks 1, 2 and 4 arrived at CLEAR
June 27 - lidar DEM tiles for blocks 1, 2 and 4 available for download
July 14 - lidar DEM tiles for block 6 arrive and available for download. That's the last of the DEMs!
July 25 - All LAS files arrive at CLEAR
Aug 11 - DEM images services up
Sept 1 - Final LAS metadata available
Sept 18 - LAS files available for download
Sept 19 - Contour tiles arrive at CLEAR
23,381 tiles covering Connecticut. Each tile is 2500ft on a side or 0.224 sq miles, 143.5 acres and 6,250,000 sq feet.
Statewide. 4 bands (red, green, blue, near-infrared). 3 inch pixels. GeoTIFFs. MrSIDs Generation 3 and Generation 4. CT State Plane NAD 83 (2011)* Feet. 8.5 TB of GeoTIFFs and 763 GB of MrSIDs (Generation 3 is 327 GB and Generation 4 is 436 GB). Captured in March and April 2016 (leaf off). Tide coordinated.
Statewide. USGS Quality Level 2. 2 points per sq meter. Ground/non-ground classification. LAS files (point cloud). Bare earth 1m pixel raster tiles (called a Digital Elevation Model or DEM). 1 foot and 5 foot contours derived from Lidar. Intensity images. Captured in March and April 2016 (leaf off). Tide coordinated.
* NAD 83 (2011) is the most current realization of NAD 83 published by the National Geodetic Survey and is consistent with the national Continuously Operating Reference Stations (CORS) Network.