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SPECIFICATIONS for CO-LOCATED DIGITAL AERIAL PHOTOGRAPHY 

This document is a reference guide for those providing digital aerial photographic services for 

Central Federal Lands Highway Division (CFLHD) of the Federal Highway Administration 

(FHWA), Lakewood, Colorado. 

I. GENERAL DESCRIPTION 

Photography will be taken at the same time that the LiDAR data is being gathered using a digital 

camera mounted in the aircraft carrying the LiDAR sensor. An inertial navigation system is to 

be employed in the aircraft to record positional data of the camera, which is used to determine 

plotter settings for softcopy digital photogrammetric workstations. 

II. TECHNICAL REQUIREMENTS 

A. The camera platform used will be a Contax 645 or another precision digital camera 

having similar performance characteristics. 

B. CFLHD will furnish photographically identifiable ground control points within the 

project area. Make the necessary adjustments to insure that the resulting photographic 

images fit the photo-identifiable ground control at a 95% confidence level to a 

horizontal accuracy of 0.5 foot and a vertical accuracy of 0.30 foot. 

C. The photographic coverage will not have less than 55% forward overlap with sufficient 

side overlap to allow for planimetric ties. 

D. The Ground Sample Distance of the digital imagery will not be more than 0.2 foot. 

E. The imagery must be free from deep shadows. To insure this, photography should be 

collected when the sun is greater than 30° above the horizon. The images must be free 

of clouds, shadows, smoke, haze, snow or other deficiencies, which would interfere with 

their intended use. 

F. Titling data is to be placed along the edge of overlap on each exposure, with the 

following information; date, photo scale, project code name and flight line exposure 

number. The project code name will be three groups of characters separated by dashes, 

beginning with “CFL“. The fourth and fifth characters represent the year, as in 07 for 

2007. The sixth and seventh characters represent the state the project lies in, as in CO 

for Colorado. The eighth, ninth, tenth and eleventh characters will designate the project 

name as provided. The code “CFL-07CO-GRSA” would indicate a 2007 project in 

Colorado named Great Sand Dunes. The project code name need only appear on the 

first and last exposures of the flight line. Exposure numbering will increase as indicated 

by the direction of the arrows on the flight line maps. Generally, this is toward the north 
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L:\SURVEY\QAQC\CFLHD Current Standards and Specifications for SMROW\CFLHD-Specifications-for-Co-Located-Digital-AerialPhotography-k.doc

and/or west. Each strip will begin with exposure number one. (This is not meant to 

dictate direction the mission is to be flown.) 

G The image files for each frame of photography will be in either TIFF or VITEC format. 

These image files are to be on DVD+R disks in 1⁄4” jewel cases with disk labels and 

jewel case inserts stating the creator’s name, date of photography, mission number and 

names and sizes of the files contained. 

H Provide a report to CFLHD to include discussion of GPS control, Geoid information and 

Airborne GPS solutions as well as camera attitude and positional data for each frame of 

photography. Provide CFLHD with all files needed to accurately set and compile 3-D 

planimetric mapping from the supplied digital imagery using the current version of 

Socet Set. 

I Provide a current camera calibration report.