Q: What format and resolutions are available and how much do they cost?
A: Imagery is in a 1ft. pixel resolution MrSID compressed format (limited availability of 6 inch resolution), with a 20:1 compression ratio, which can viewed by any ArcGIS application or the free LizardTech application, available at http://www.lizardtech.com (this application also allows users to “right-click and Save As” a TIFF file or other image formats). TIFF images available to GDC members only.
Pricing:
1-8 lamberts (for FTP download or CD) $50 each
9-15 lamberts (for FTP download or CD) $35 each
Full Coverage (external hard drive) $1,500 (the whole coverage area is more than 1,800 lamberts and we will provide a 100GB external hard drive)
Q: What is a Lambert and how big is a Lambert grid?
A: Imagery data is tiled according to the Lambert grid system. Each Lambert covers approximately a 4 square mile area.
Q: For which years do you have aerials available and which counties are included for each year?
A: We have aerials for 2002, 2004, 2006. The aerials imagery is available for the following counties: Brazoria, Fort Bend, Galveston, Harris, Montgomery, Waller, and some parts of neighboring counties. The coverage is very similar each year with the same coordinate system, projection and file format, but the coverage varies in that each year the vendor provided a new flyover. Please refer to the coverage maps on the Aerials web page for a complete coverage of each year.
Q: Are the aerial photos projected to a coordinate system?
A: The coordinate system and projection for this imagery is: State Plane, Texas South Central Zone (FIPS code 4204), Feet, NAD83, GRS 1980.
Q: Will the aerial include metadata?
A: Metadata are available for the 2006 aerial imagery.
For 2006 aerial image metadata for 6 inch, click here.
For 2006 aerial image metadata for 1 foot, click here.
Q: Do you have any way to cross check the image by address?
A: Yes, by using ESRI software.
Q: Is your imagery orthorectified?
A: Yes, the Aerials are orthorectified.
Q: How long does it take to get the aerials to us?
A: For an order of less than 16 Lamberts you will receive an instructional email within 24 hours with a download link from our web site.
For the entire coverage you will receive a confirmation message when your order will be shipped, usually within 3-7 business days.
Q: Is the photography true color and not infrared or black & white?
A: Yes, it is True/Natural Color and not CIR or Black & White.
Q: Could please let me know what the photo date is for the 2006 aerial imagery you have for the Houston-Galveston area?
A: Mid-January 2006
Q: How do I make out the check and what other paperwork do you need to make sure you get the money?
A: It should be made payable to the Houston-Galveston Area Council. Please note on the check that it is for "Aerials Purchase". Please mail it to:
Houston-Galveston Area Council
Data Services Department
3555 Timmons Lane, Suite 120
Houston, TX 77027-6478
Q: What would the cost be for educational use?
A: The same as for commercial use.
Links
2002 Coverage Map
2004 Coverage Map
2006 Coverage Map