FGDC Classic | FGDC FAQ | FGDC Plus | XML

2010 Connecticut Coastal 4Band Aerial Photography Project
File Geodatabase Raster Dataset - FGDBR - ORTHO_2010_COAST_4BAND
FGDC, ESRI Metadata
DescriptionGraphicSpatialData StructureData QualityData SourceData DistributionMetadata
+ Resource Description
Citation
Information used to reference the data.
Title: 2010 Connecticut Coastal 4Band Aerial Photography Project
Originators: PhotoScience, Inc (data compiler)
State of Connecticut Department of Environmental Protection (data maintainer and publisher)
Publisher: State of Connecticut Department of Environmental Protection
Publication place: Hartford, CT
Publication date: 2010
Edition: 2010
Data type: Fgdb raster digital data
Data location: http://ct.gov/dep
Larger Work Citation
Title: 2010 Connecticut Multispectral Coastal Digital Orthophotography Project
Originators: PhotoScience, Inc. is the collector and creator of the data (compiler). The State of Connecticut Department of Environmental Protection is maintainer and producer (publisher) of this data for use.
Publication date: 2010
Edition: 2010
Other citation details:
The 2010 Connecticut Multispectral Coastal Imagery Project includes the following products: 821 individual, unrectified 4-band images; 589 4-band orthorectifed images compiled from the indivudual images; photo capture points; orthorectified mosiac lines; FGDC compliant metadata for all GIS-based products; and project documentation (QA/QC reports, accuracy analysis, Aerial triangulation and ground survey reports.) The project was made possible through the NOAA Coastal Services Center Coastal Geospatial Services Contract (CGSC), a FAR Part 36, Architectural and Engineering Contract vehicle to provide geospatial services.
Description
A characterization of the data, including its intended use and limitations.
Abstract:
The 2010 Connecticut Multispectral Coastal Digital Orthophotography is 1:12,000-scale, 4-band (red, green, blue, and near infrared) tide controlled orthorectified imagery.   These data were compiled from a set of 821 individual vertical aerial images taken over 3 distinct days during a June 15 to September 15, 2010 flight window.  The indivudual orthophotos have been subsequently mosaicked into a composite that can be configured to show either true color or color infrared versions of the coastal landscape.

The geographic extent (~320 sq mi) of the photography includes: 
* all land areas within one-thousand (1000) feet of Mean High Water (MHW) and within one-thousand (1000) feet of state-regulated tidal wetlands;
* an area of at least two-thousand (2000) feet waterward of the immediate shoreline of Long Island Sound in order to clearly depict the interface between the shorelands and coastal waters;  
* all offshore islands within the territorial borders of the State of Connecticut including Goose Island and Falkner Island (offshore of Branford); Calf Islands and Great Captain Island (offshore of Greenwich); Norwalk Islands (offshore of Norwalk); Thimble Islands (offshore of Branford); Sandy Point (offshore of Stonington); and all islands in the Connecticut part of Fishers Island Sound; and  
* the main stem of the Connecticut River up to the Massachusetts State line.  

To maximize the quality of the images and their contents, photography also conformed to the following flight specifications:
* photos were only taken during times of no/minimal cloud cover when lighting and weather conditions optimized the data collection;   
* solar altitude was no more than 65 degrees and no less than 30 degrees;
* the ground detail was not obscured by flooding; 
* the foliage (salt marsh vegetation in particular) was fully developed;
* seasonal conditions (summer) favored maximum human use/recreation activities (e.g., boats & temporary docks/structures in water, etc.)
* photo times were planned within 1 hour window before or after a predicted low tide based on National Oceanic & Atmospheric Administration (NOAA) predicted tide tables.
* Forward overlap is 60% and side image overlap is 30%
* Crab and Tilt do not exceed 5 degrees.

The individual aerial photos were first orthorectifed and mosaicked into grid-based system provided by the State of Connecticut Department of Environmental Protection.   Adjacent tiles are edgematched with no gaps.  Temporal and seasonal differences between source images were minimized to avoid incongruence across join lines. When a mosaic of source images was made, the image judged by visual inspection to have the best contrast was used as the reference image. The brightness values of the other images were adjusted to match that of the reference image. The join lines between the overlapping images were hosen to minimize tonal variations. Localized adjustment of the brightness values were performed to minimize tonal differences between join areas. 

Subsequent mocaicking took the individual orthophotos and combined them into a project-wide composite.

The ground resolution of the imagery is approximately 1 ft per pixel.  Data is compiled at 1:12,000 scale. This data is not updated.
Purpose:
The 2010 Connecticut Multispectral Coastal Digital Orthophotography is 1:12,000-scale 4 band (red, green, blue, & near infrared) tide controlled imagery.  It depicts land use, natural resources, vegetation, and other features and characteristics in the immediate shoreline areas of Connecticut during the summer of 2010 within one hour of a predicted low tide both in true color or color infrared, depending on the band configuration.  Use this layer as photo representation for depicting coastal features/landscapes or to analyze the landscape, features, or activities of the coastal area.  

NOTE: This data is georeferenced, so it can be combined with other GIS data with real world coordinates.  An un-rectified version of this data (2010 Connecticut Multispectral Coastal Imagery) constituting the source data for the orthophtography is also available for use.
Supplemental information:
The imagery exists as 1:12,000 4-band (red, green, blue, near infrared) multispectral images.  When bands are configured as follows: red = 1, green = 2, blue = 3, the imagery will render as true color - the same color the human eye naturally discerns.  When bands are configured as follows: red = 4, green = 1, blue = 2, the imagery will render as color infrared.

A digital orthophoto is a digital image of an aerial photograph in which displacements caused by the camera and the terrain have been removed. It combines the image characteristics of a photograph with the geometric qualities of a map. A digital orthophoto has the same scale throughout and can be used as a map for measuring distances, calculating areas, determining the shape of features, and reading coordinate locations, for example. Digital orthophotos provide the necessary background (base map) layer information to which other spatial data layers are registered or created.  The process of creating an orthophoto, orthorectification, corrects the geometry of a aerial photo image so that it appears as though each pixel were acquired from directly overhead. Orthorectification uses elevation data to correct terrain distortion in aerial or satellite imagery.

Color infrared photography, often called false color photography because it renders the scene in other than the normal colors seen by the human eye, is widely used for interpretation of natural resources.  Atmospheric haze does not interfere with the acquisition of the image, therefore is well suited to aerial photography.  Because the film is high speed and subject to degrees of degradation in handling before exposure, the aerial photographs can vary in overall tone.  This variability can complicate the interpretation of color tones between photographs, but some general guidelines can be given to aid the inexperienced interpreter. 

* The red tone of color infrared aerial photographs is almost always associated with live vegetation. Very intense reds indicate vegetation which is growing vigorously and is quite dense.  Knowledge of the vigor and density of vegetation is important to the interpretation of the red colors on color infrared aerial photography. 

* As the vigor and density of vegetation decreases, the tones may change to light reds and pinks. If plant density becomes low enough the faint reds may be overcome by the tones of the soils on which the plants are growing. The ground areas in this case will appear in shades of white, blue, or green depending on the kind of soil and its moisture content. As plant vigor decreases, the vegetation will show as lighter shades of red and pink, various shades of greens, and possible tans.  Dead vegetation will often be shades of greens or tans. 

* Bare soils will appear as shades of white, blue, or green in most agricultural regions.  In general, the more moist the soil the darker the shade of that particular soil color. Composition of the soil will affect the color tones shown on the photographs.  Dry sand will appear white and, with more moisture, may be very light gray or possibly light tan.  Clayey soils will generally be darker in color than sands and tend toward tans and bluegreens.  Again, wetter clays will be darker shades of the same tones.  Soils high in organic matter, like silts and loams will be even darker in color, and usually in shades of blues and greens.  Wet organic soils can be very dark blue or green in the aerial photographs. 

* Man-made features will show in the tones that relate to the materials they are made of.  Asphalt roads, for example, will be dark blue or black, gravel or dirt roads will show as lighter colors, depending on the soil materials involved in their composition, and concrete roads will appear light in tone, assuming clean concrete.  The buildings and streets of towns can be considered in a similar manner, their color dependent on the material they are made of. 

* Water will appear as shades of blue, varying from nearly black to very pale blue.  Clear, clean water will appear nearly black.  As the amount of sediment increases, the color becomes increasingly lighter blue.  Very shallow water will often appear as the material present in the bottom of the stream.  For example, a very shallow stream with a sandy bottom will appear white due to the high level of reflection of the sand. 

* Degraded film will result in photographs which have an overall blue or green cast.  When that occurs, the interpretation must consider what that overall cast will do to a "normal" rendition of the scene. 

(Description and guidelines for color infrared photography taken from the United States Geological Survey Aerial Photo FAQ web page, http://edc.usgs.gov/guides/news/aerialfaq.htmlt#A10)
Dataset credit:
Photoscience, Inc., of Lexington, KY performed the 2010 Connecticut Multispectral Coastal Imagery Project via an MOU between the State of Connecticut Department of Environmental Protection and the NOAA Coastal Services Center as part of the Coastal Geospatial Services Contract (CGSC), a FAR Part 36, Architectural and Engineering Contract vehicle to provide geospatial services.
Language of dataset: en
Point Of Contact
Contact information for the individual or organization that is knowledgeable about the data.
Organization: State of Connecticut Department of Environmental Protection
Person: Kevin O'Brien
Phone: 860-424-3034
Fax: 860-424-4054
Email: dep.gisdata@po.state.ct.us
Hours of service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Address type: mailing and physical address
Address:
79 Elm St.
City: Hartford
State or Province: CT
Postal code: 06106-5127
Country: US
Data Type
How the data are represented, formatted and maintained by the data producing organization.
File or table name: ORTHO_2010_COAST_4BAND
Data type: Fgdb raster digital data
Data format: File Geodatabase Raster Dataset
Native dataset environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.1.3000
Time Period of Data
Time period(s) for which the data corresponds to the currentness reference.
Date: 20100615
Date: 20100618
Date: 20100619
Currentness reference:
ground condition
Status
The state of and maintenance information for the data.
Data status: Complete
Update frequency: None planned
Key Words
Words or phrases that summarize certain aspects of the data.
Theme:
Keywords: imageryBaseMapsEarthCover
Keyword thesaurus: ISO 19115 Topic Category
Place:
Keywords: Connecticut, CT
Keyword thesaurus: U.S. Department of Commerce, 1987, Codes for the Identification of the States, the District of Columbia and the Outlying Areas of The United States, and Associated Areas (Federal Information Processing Standard 5-2): Washington, DC, National Institute of Standards and Technology.
Data Access Constraints
Restrictions and legal prerequisites for accessing or using the data after access is granted.
Access constraints:
None. The data is in the public domain and may be redistributed.  Please include this metadata record in any redistributions.
Use constraints:
No restrictions or legal prerequisites for using the data. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:12,000 scale (1 inch = 1,000 feet). Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the State of Connecticut, Department of Environmental Protection as the source for this information. For example, include the following data source description when printing this layer on a map: "2010 Connecticut Multispectral Coastal Digital Orthophotography, compiled by PhotoScience, Inc. and published by the State of Connecticut, Department of Environmental Protection. Source map scale is 1:12,000."
Data Security Information
Handling restrictions imposed on the data because of national security, privacy or other concerns.
Security classifiction system: None
Security classification: Unclassified
Security handling: None
Cross Reference
Information about other, related data sets that are likely to be of interest.
Title: Aerial Imagery
Originators: Photo Science, Inc.
Series name: Aerial Imagery
Series identification: 7525-037: Conneticut Shoreline
Publisher: Photo Science, Inc.
Publication place: Lexington, KY
Publication date: 2010
+ Graphic Example
Browse Graphic
Graphic illustration of the data.
Browse graphic 1
Open - 2010 Coastal Detail View - Color
Graphic Image

Browse graphic 2
Open - 2010 Coastal Detail View - Color Infrared
Graphic Image

Browse graphic 3
Open - 2010 Coastal Detail View - Color / Color Infrared
Graphic Image

Browse graphic 4
Open - 2010 Coastal Data Coverage - Color Infrared
Graphic Image

Browse graphic 5
Open - 2010 Coastal Data Coverage - Color
Graphic Image
+ Spatial Reference Information
Horizontal Coordinate System
Reference system from which linear or angular quantities are measured and assigned to the position that a point occupies.
Projected coordinate system:
Name: NAD 1983 StatePlane Connecticut FIPS 0600 Feet
Map units: survey feet
Geographic coordinate system:
Name: GCS North American 1983
Coordinate System Details
Map projection
Map projection name: Lambert Conformal Conic
Standard parallel: 41.200000
Standard parallel: 41.866667
Longitude of central meridian: -72.750000
Latitude of projection origin: 40.833333
False easting: 999999.999996
False northing: 499999.999998
Planar Coordinate Information
Planar coordinate encoding method: row and column
Coordinate representation:
Abscissa resolution: 1.000000
Ordinate resolution: 1.000000
Planar distance units: survey feet
Geodetic model
Horizontal datum name: North American Datum of 1983
Ellipsoid name: Geodetic Reference System 80
Semi-major axis: 6378137.000000
Denominator of flattening ratio: 298.257222
Vertical Coordinate System
Reference system from which vertical distances (altitudes or depths) are measured.
Altitude system definition:
Altitude datum name: North American Vertical Datum of 1988
Altitude resolution: 1.000000
Altitude distance units: Feet
Altitude encoding method: Explicit elevation coordinate included with horizontal coordinates
Spatial Domain
The geographic areal domain of the data that describes the western, eastern, northern, and southern geographic limits of data coverage.
Bounding Coordinates
In Projected or local coordinates
NAD 1983 StatePlane Connecticut FIPS 0600 Feet
Boundary Coordinate
Left 746900.000000 (survey feet)
Right 1257300.000000 (survey feet)
Top 944100.000000 (survey feet)
Bottom 551400.000000 (survey feet)
In Unprojected coordinates (geographic)
GCS North American 1983
Boundary Coordinate
West -73.681835 (longitude)
East -71.802703 (longitude)
North 42.052120 (latitude)
South 40.970596 (latitude)
+ Data Structure and Attribute Information
Overview
Summary of the information content of the data, including other references to complete descriptions of entity types, attributes, and attribute values for the data.
Direct spatial reference method: Raster
Attributes of 2005_photocenters
Detailed descriptions of entity type, attributes, and attribute values for the data.
Description:
Color orthophotos are comprised of RGB and NIR bands.
Source:
None
Raster Information
Type and number of raster spatial objects in the data.
Raster format: FGDBR
Raster object type: Pixel
Number of raster bands: 4
Raster properties
Raster origin: Upper Left
Has pyramid layers: TRUE
Has image colormap: FALSE
Compression type: JPEG2000
Raster display type: pixel codes
Cell information
Number of cells on x-axis: 510400
Number of cells on y-axis: 392700
Number of cells on z-axis: 1
Bits per cell: 16
Cell Size:
X direction: 1.000000
Y direction: 1.000000
+ Data Quality and Accuracy Information
General
Information about the fidelity of relationships, data quality and accuracy tests, omissions, selection criteria, generalization, and definitions used to derive the data.
Logical consistency report:
Compliance with the required horizontal accuracy standard is supported by the placement of photo identifiable ground control points and the collection of airborne GPS and IMU data during the aerial missions. Horizontal accuracy was validated by comparing the ground control values (X,Y) of each photo identifiable ground control point obtained using survey grade GPS with its corresponding values (X,Y) measured from the final orthophoto. An overall horizontal RMSE x or y value was then calculated to verify compliance with the required horizontal accuracy not to exceed 4 foot RMSE X or Y. All GeoTIFF tagged data and image file sizes are validated using commercial GIS software to ensure proper loading before being archived.   This validation procedure ensures correct physical format and field values for tagged elements.  Seamlines and tile edges are visually inspected.
Completeness report:
The 2010 Connecticut Multispectral Coastal Digital Orthophotography is complete in the sense that it accurately reflects the content from the 2010 Connecticut Multispectral Coastal Imagery Project available at the time Photoscience, Inc. created the data.  However, compared to current conditions, the 2010 Connecticut Multispectral Coastal Digital Orthophotography may be incomplete. This data is not updated.
Cloud cover: 0
Attribute Accuracy
Accuracy of the identification of data entities, features and assignment of attribute values.
Attribute accuracy report:
RMSE Requirements needed here.
Positional Accuracy
Accuracy of the positional aspects of the data.
Horizontal accuracy report:
Spatial Information Solution's Accuracy Analyst was used to check 36 ground control points.  The generated report is available upon request.
Horizontal positional accuracy assessment:
Accuracy values
8.28
Explanation:
CE95 in feet
Vertical accuracy report:
There is no vertical component for this set of orthoimagery.
Vertical positional accuracy assessment:
Accuracy values
0
Explanation:
There is no vertical component for this set of orthoimagery.
+ Data Source and Process Information
Data Sources
Information about the source data used to construct or derive the data.
Data source information
PLAN
Title: Flight Plan
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Planned Photo Centers.
Date: 2010
Currentness reference:
publication date
RAWs
Title: RAWs
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Digital stereoscopic aerial imagery was obtained using a large format Zeiss/Intergraph Digital Mapping Camera (DMC) over 3 flight dates comprised of 4 missions. Aerial imagery was supplemented with the simultaneous acquisition of airborne GPS/IMU data, which captured the ground coordinate for the nadir point of each photograph. Aerial imagery was exposed at an altitude of approximately 9800' above mean terrain yielding an approximate GSD of 1 ft. The aerial images are used to AT the project and in the production of orthophotos.
Date: 20100615
Date: 20100618
Date: 20100619
Currentness reference:
Ground Condition
GCP
Title: Ground Control Points
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Photo Science, Inc. established a combination of photo identifiable and limited targeted ground control points to create a digital control file and control report used in the ortho production and QA processes. Predefined points within each collection block were measured using a combination of GPS and conventional survey techniques. These points along with their precise coordinates and elevations were used in the AT process and to check the horizontal accuracy of the resulting orthophotos. The X and Y coordinates were expressed in CT SPCS NAD83, US Survey Feet and Z elevation were expressed in NAVD 1988, US Survey Feet.  A total of 41 control points were.  Details of the Ground Control Survey Phase can be found in Photo Science's full control report.
Date: 2010
Currentness reference:
Publication Date
EO
Title: External Orientation
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Exterior Orientation (EO) Parameters (x,y,z,omega,phi,kappa) are produced to provide precise photocenter locations for each frame of imagery.
Date: 2010
Currentness reference:
Publication Date
AT Report
Title: Aerotriangulation Report
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
SoftCopy Aerotriangulation is a computer process of densifying the ground control network from locations in a few of the digital images to numerous points in each digital image that is to be used in the mapping process. This process is dependent on the location and coordinate positions of the ABGPS and GPS photo control points as well as a precise camera calibration for the DMC camera used to capture the images.
Date: 2010
Currentness reference:
Publication Date
DEM
Title: LiDAR Digital Elevation Model Surface
Originators: NOAA Coastal Services Center for the Connecticut Department of Environmental Protection
Publication date: 2000
Media: stable-based media
Source contribution:
The LIDAR elevation data used for the rectification of the orthophotos was provided by NOAA Coastal Services Center for the Connecticut Department of Environmental Protection.
Date: 2000
Currentness reference:
Publication Date
TILES
Title: Orthophotography Tiles
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
The tiled orthophoto is the result of mosaicking orthorectified imagery and using the tile definition to cut into manageable, usable orthophotos.
Date: 2010
Currentness reference:
Publication Date
MOSAIC
Title: Orthophoto Mosaic
Originators: State of Connecticut, Deprt of Environmental Protection
Publication date: 2011
Source contribution:
The orthophoto mosaic is the result of mosaicking orthorectified imagery into a composite project wide dataset.
Date: 2010
Currentness reference:
ground condition
Process Steps
Information about events, parameters, tolerances and techniques applied to construct or derive the data.
Process step information
Process Step 1
Process description:
Imagery Acquisition:

A set of 821 individual aerial photos were taken over 3 distinct days during a June 15 to September 15, 2010 flight window. The geographic extent (~320 sq mi) of the photography includes: 
* all land areas within one-thousand (1000) feet of Mean High Water (MHW) and within one-thousand (1000) feet of state-regulated tidal wetlands;
* an area of at least two-thousand (2000) feet waterward of the immediate shoreline of Long Island Sound in order to clearly depict the interface between the shorelands and coastal waters;  
* all offshore islands within the territorial borders of the State of Connecticut including Goose Island and Falkner Island (offshore of Branford); Calf Islands and Great Captain Island (offshore of Greenwich); Norwalk Islands (offshore of Norwalk); Thimble Islands (offshore of Branford); Sandy Point (offshore of Stonington); and all islands in the Connecticut part of Fishers Island Sound; and  
* the main stem of the Connecticut River up to the Massachusetts State line.  

To maximize the quality of the images and their contents, photography also conformed to the following flight specifications:
* photos were only taken during times of no/minimal cloud cover when lighting and weather conditions optimized the data collection;   
* solar altitude was no more than 65 degrees and no less than 30 degrees;
* the ground detail was not obscured by flooding; 
* the foliage (salt marsh vegetation in particular) was fully developed;
* seasonal conditions (summer) favored maximum human use/recreation activities (e.g., boats & temporary docks/structures in water, etc.)
* photo times were planned within 1 hour window before or after a predicted low tide based on National Oceanic & Atmospheric Administration (NOAA) predicted tide tables.
* Forward overlap will be 60% and side image overlap will be 30%
* Crab and Tilt will not exceed 5 degrees.  

All flight plans were approved by CTDEP prior to flight operations.

Flight Info: 

Flight # 1 on 6/15/2010 
* Date: 06/15/2010
* Time: 8:10AM - 11:47 (EST) 
* Aircraft #: N62923
* Camera Type: DMC
* Camera Serial #: 131
* Focal Length (mm): 120
* # Flight Lines: 10 lines were flown (see flight logs)
* AbGPS and IMU were used to obtain the omega, phi and kappa values

Flight #1 on 6/18/2010
* Date: 06/18/2010
* Time: 8:38 - 11:20 (EST)
* Aircraft #: N62923
* Camera Type: DMC
* Camera Serial #: 131
* Focal Length (mm): 120
* # Flight Lines: 14 lines were flown (see flight logs)
* AbGPS and IMU were used to obtain the omega, phi and kappa values

Flight #2 on 6/18/2010
* Date: 06/18/2010
* Time: 2:00 -  3:29 (EST)
* Aircraft #: N62923
* Camera Type: DMC
* Camera Serial #: 131
* Focal Length (mm): 120
* # Flight Lines: 4 lines were flown (see flight logs)
* AbGPS and IMU were used to obtain the omega, phi and kappa values

Flight # 1 on 6/19/2010
* Date: 06/19/2010
* Time: 10:43 - 11:25 (EST)
* Aircraft #: N62923
* Camera Type: DMC
* Camera Serial #: 131
* Focal Length (mm): 120
* # Flight Lines: 3 lines were flown (see flight logs)
* AbGPS and IMU were used to obtain the omega, phi and kappa values

All flight data was QA/QC inspected by PhotoScience Inc. and the NOAA Coastal Services Center prior to shipment to the State of Connecticut, Department of Environmental Protection for final QA/QC.  No areas were required to be reflown.
Process date: 20100915
Data Source used
PLAN
Title: Flight Plan
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Planned Photo Centers.
Date: 2010
Currentness reference:
publication date
Data Source produced
RAWs
Title: RAWs
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Digital stereoscopic aerial imagery was obtained using a large format Zeiss/Intergraph Digital Mapping Camera (DMC) over 3 flight dates comprised of 4 missions. Aerial imagery was supplemented with the simultaneous acquisition of airborne GPS/IMU data, which captured the ground coordinate for the nadir point of each photograph. Aerial imagery was exposed at an altitude of approximately 9800' above mean terrain yielding an approximate GSD of 1 ft. The aerial images are used to AT the project and in the production of orthophotos.
Date: 20100615
Date: 20100618
Date: 20100619
Currentness reference:
Ground Condition
Process Step 2
Process description:
Ground Surveying: Ground Control points were collected from July 10, 2010 to July 14, 2010 by P. Hrabak of Photo Science, Inc..  A total of 41 Photo Identifiable (PID's) features were collected for this project.  Static GPS observation sessions were of 30 minutes apiece, using a Trimble 5700 receiver and a Zephyr Geodetic antenna on a 2.0 meter fixed height tripod.  PDOP prediction was accomodated, only collecting data when values were predicted to be less than 4.0 and with 6 or more satellites, using an elevation mask of 15 degrees.  A data log sheet was filled out on each occupation.  Four photographs were taken of each point from four different directions.  High-contrast corners of pavement, especially concrete adjoining dark asphalt or grass, were favored, and were selected in evenly-spaced, open, well-exposed areas where the planned aerial imagery footprints had maximum overlap.  See the full Survey Report for more details.
Process date: 2010
Data Source used
PLAN
Title: Flight Plan
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Planned Photo Centers.
Date: 2010
Currentness reference:
publication date
Data Source produced
GCP
Title: Ground Control Points
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
Photo Science, Inc. established a combination of photo identifiable and limited targeted ground control points to create a digital control file and control report used in the ortho production and QA processes. Predefined points within each collection block were measured using a combination of GPS and conventional survey techniques. These points along with their precise coordinates and elevations were used in the AT process and to check the horizontal accuracy of the resulting orthophotos. The X and Y coordinates were expressed in CT SPCS NAD83, US Survey Feet and Z elevation were expressed in NAVD 1988, US Survey Feet.  A total of 41 control points were.  Details of the Ground Control Survey Phase can be found in Photo Science's full control report.
Date: 2010
Currentness reference:
Publication Date
Process Step 3
Process description:
Aerotriangulation: Softcopy aerotriangulation was performed by Photo Science to supplement and extend ground control and ABGPS / IMU control data. Aerotriangulation constructs a detailed model of the position of each pass point and provides residuals (and blunders) at all photo control locations. The end result is not only the referenced image, but also a coordinate listing of all of the points and corresponding residuals.  This process enabled photogrammetric production of the orthophotography requirements. According to the scope of work, accuracy is stated: Positional Accuracy should be at least as good as the National Map Accuracy Standards for the nominal scale of the output.  The AT computations were based on a projection of the Conneticut State Plane Coordinate System and a datum of NAD83. Vertical computations were based NAVD88. All final coordinate and elevation values were expressed in US Survey Feet. A digital image of the aerial photography was utilized to compare and measure the coordinates of selected pass points, (min. 9 per image) with the exception of end images, which have a minimum of 6 per image. Pass points were either dark spots on the ground, corner intersections of sidewalks, rocks, or road lines to name a few. These pass points and any ground based photo control points were measured using the calibration statistics to adjust measurements for the specific camera characteristics. Computer routines (relative and absolute) provide analysis of all pass points, tie points, ABGPS and photo control points. Once all strips were checked for completeness, the strips were assembled into a block where a second degree block adjustment was run along with the full least squares bundle adjustment. Once the last set of blunders and adjustments are complete, a final block bundle adjustment is run to produce the final solution using a rigorous simultaneous least squares bundle adjustment. The bundle adjustment was then run with minimal ground control to test the photogrammetric measurements for consistency. Next, the full ground control data set, including the ABGPS data, was added to the adjustment. The horizontal control was then tightened and the effect on the vertical control and the photogrammetric residuals were inspected. Results of the Aerotriangulation Phase can be found in Photo Science's AT reports.
Process date: 2010
Data Source used
RAWs, GCP, EO
Data Source produced
AT Report
Title: Aerotriangulation Report
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
SoftCopy Aerotriangulation is a computer process of densifying the ground control network from locations in a few of the digital images to numerous points in each digital image that is to be used in the mapping process. This process is dependent on the location and coordinate positions of the ABGPS and GPS photo control points as well as a precise camera calibration for the DMC camera used to capture the images.
Date: 2010
Currentness reference:
Publication Date
Process Step 4
Process description:
Digitial Orthophoto Processing: The ortho rectification process required as input a digital elevation model (DEM), imagery (RAW), camera calibration and aerotriangulation exterior orientation file (AT Report). The orthorectified imagery was produced using Intergraph OrthoPro software. It uses ImageStation Photogrammetric Manager (ISPM) for photogrammetry project setup, file management, and importing triangulation data from a user defined ASCII file (EO). The ortho project recorded all the operations, including all the parameters that are defined through the OrthoPro workflow, such as the project area coordinates, pixel size, rotation angle, ISPM project and its unorthorectified source images, product areas (index) orthorectification settings, seamlines and so on. The results were single frame images ready for mosaicking into manageable tiled orthos. The single frame orthos were checked for accuracy against the surveyed ground control before further image editing. 
Orthorectified imagery was mosaicked, locally color-balanced and cut to the tile definition boundaries using Intergraph OrthoPro software. Tiled orthophotos undergo a rigorous manual QC process to evaluate for remaining hotspots (sun reflectance over water), tone quality, color balance and the feathering area along seamlines. Any imperfections at this point were manually edited. Radiometry is verified by visual inspection of the digital orthophoto. Slight systematic radiometric differences may exist between adjacent orthoimage files; these are due primarily to differences in source image capture dates and sun angles along flight lines. These differences can be observed in an image's general lightness or darkness when it is compared to adjacent orthoimage file coverages. Tonal balancing may be performed over a group of images during the mosaicking process which may serve to lighten or darken adjacent images for better color tone matching. The final 1' GSD, tiled, 4 band (R,G,B), 16 bit, ortho images were then converted to the required GeoTIFF file format.
Each TIF was processed to replace 0 values with 1 values inside valid imagery files, then pixels not inside the valid imagery were converted to 0,0,0,0 to represent NoData values.
Process date: 2010
Data Source used
RAWs, GCP, AT Report, DEM
Data Source produced
Tiles
Process Step 5
Process description:
This step combines all of the indivdual orthophoto tiles into a composiet mosaic using the following procedure:

1. Create File Geodatabase (FGB)
2. Create a new raster dataset (theMosiac) to mosaic into:
a. Output location/name = FGB/theMosaic
b. Cellsize = 1
c. Pixel Type = 16 bit unsigned
d. Spatial Ref = CTSP NAD83 ft
e. Bands = 4
f. Environment settings/Raster Storage:
i. Config Keyword  = omit, leave blank
ii. Build Pyramids = yes
iii. Pyramids Levels = 1 2
iv. Pyramid resampling = Bilinear
v. Tile Size:  accept defaults
vi. Compression = JPEG2000
vii.Compression Quality = 40
viii. Pyramid Reference Pt: 687800, 1015180
3. From theMosaic, load reprocessed TIFFs:
a. Mosiac Method = Last (default)
b. Mosaic  Colormap = First (default)
c. Background value = 0
d. No Data value = omit, leave blank
e. Convert 1 bit to 8 bit = omit, leave blank
f. Mosaic tolerance = 0 (default)
g. Color matching = none (default)
h. Environment settings/Raster Storage:
i. Build Pyramids = yes
ii. Pyramid Levels = 12
iii. Pyramid resampling = Bilinear
iv. Calculate statistics = yes, accept defaults
v. Compression = JPEG2000
vi. Compression Quality = 40
vii. Tile Size = accept defaults
Process date: 2011
Data Source used
TILES
Title: Orthophotography Tiles
Originators: Photo Science, Inc.
Publication date: 2010
Media: stable-based media
Source contribution:
The tiled orthophoto is the result of mosaicking orthorectified imagery and using the tile definition to cut into manageable, usable orthophotos.
Date: 2010
Currentness reference:
Publication Date
Data Source produced
MOSAIC
Title: Orthophoto Mosaic
Originators: State of Connecticut, Deprt of Environmental Protection
Publication date: 2011
Source contribution:
The orthophoto mosaic is the result of mosaicking orthorectified imagery into a composite project wide dataset.
Date: 2010
Currentness reference:
ground condition
+ Data Distribution Information
General
Description of the data known by the party from whom the data may be obtained, liability of party distributing data, and technical capabilities required to use the data.
Resource description:
2010 Connecticut Coastal 4Band Aerial Photography Project
Distribution liability:
The data is in the public domain and may be redistributed.  No restrictions or legal prerequisites for using the data. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:12,000 scale (1 inch = 1,000 feet). Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the State of Connecticut, Department of Environmental Protection as the source for this information. For example, include the following data source description when printing this layer on a map: "2010 Connecticut Multispectral Coastal Digital Orthophotography, compiled by PhotoScience, Inc. and published by the State of Connecticut, Department of Environmental Protection. Source map scale is 1:12,000."
Technical prerequisites:
Geographic information sytem (GIS), computer-aided drawing or other mapping software is necessary to display, view and access the information.
Distribution Point of Contact
Contact information for the individual or organization distributing the data.
Organization: State of Connecticut, Department of Enviromental Protection
Phone: 860-424-3034
Fax: 860-424-4054
Email: dep.gisdata@po.state.ct.us
Hours of service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Address type: mailing and physical address
Address:
79 Elm St.
City: Hartford
State or Province: CT
Postal code: 06106-5127
Country: USA
Standard Order Process
Common ways in which data may be obtained.
Digital form:
Format name: RPF
Transfer size: 0.000
Digital transfer option:
Online option:
Computer information:
Network address:
Network resource name: dep.gisdata@po.state.ct.us
Fees: Copies of the data may be accessed without charge.
Custom Order Process
Description of custom distribution services available.
Custom order process:
The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.
+ Metadata Reference
Metadata Date
Dates associated with creating, updating and reviewing the metadata.
Last updated: 20110606
Language of metadata: en
Metadata Point of Contact
Contact information for the individual or organization responsible for the metadata information.
Organization: State of Connecticut, Department of Environmental Protection
Person: Kevin O'Brien
Phone: 860-424-3034
Fax: 860-424-4054
Email: dep.gisdata@po.state.ct.us
Hours of service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Address type: mailing and physical address
Address:
79 Elm St.
City: Hartford
State or Province: CT
Postal code: 06106-5127
Country: USA
Metadata Security Information
Handling restrictions imposed on the metadata because of national security, privacy or other concerns.
Security classifiction system: None
Security classification: Unclassified
Security handling: None
Metadata Standards
Description of the metadata standard used to document the data and reference to any additional extended profiles to the standard used by the metadata producer.
Standard name: FGDC Content Standards for Digital Geospatial Metadata
Standard version: FGDC-STD-001-1998
Time convention: local time
Metadata profiles defining additonal information:
Profile: ESRI Metadata Profile
Profile: ESRI Metadata Profile
Profile: ESRI Metadata Profile
Profile: ESRI Metadata Profile
FGDC Plus Metadata Stylesheet
Stylesheet: FGDC Plus Stylesheet
File name: FGDC Plus.xsl
Version: 2.2
Description: This metadata is displayed using the FGDC Plus Stylesheet, which is an XSL template that can be used with ArcGIS software to display metadata. It displays metadata elements defined in the Content Standard for Digital Geospatial Metadata (CSDGM) - aka FGDC Standard, the ESRI Profile of CSDGM, the Biological Data Profile of CSDGM, and the Shoreline Data Profile of CSDGM. CSDGM is the US Federal Metadata standard. The Federal Geographic Data Committee originally adopted the CSDGM in 1994 and revised it in 1998. According to Executive Order 12096 all Federal agencies are ordered to use this standard to document geospatial data created as of January, 1995. The standard is often referred to as the FGDC Metadata Standard and has been implemented beyond the federal level with State and local governments adopting the metadata standard as well. The Biological Data Profile broadens the application of the CSDGM so that it is more easily applied to biological data that are not explicitly geographic (laboratory results, field notes, specimen collections, research reports) but can be associated with a geographic location. Includes taxonomical vocabulary. The Shoreline Data Profile addresses variability in the definition and mapping of shorelines by providing a standardized set of terms and data elements required to support metadata for shoreline and coastal data sets. The FGDC Plus Stylesheet includes the Dublin Core Metadata Element Set. It supports W3C DOM compatible browsers such as IE7, IE6, Netscape 7, and Mozilla Firefox. It is in the public domain and may be freely used, modified, and redistributed. It is provided "AS-IS" without warranty or technical support.
Instructions: On the top of the page, click on the title of the dataset to toggle opening and closing of all metadata content sections or click section links listed horizontally below the title to open individual sections. Click on a section name (e.g. Description) to open and close section content. Within a section, click on a item name (Status, Key Words, etc.) to open and close individual content items. By default, the Citation information within the Description section is always open for display.
Download: FGDC Plus Stylesheet is available from the ArcScripts downloads at www.esri.com.