Hailstorm damage to the Space Shuttle's External Tank inspired a NASA innovation with extensive photography applications. In order to measure the defects caused by the storm, Kennedy Space Center used telephoto lenses to zoom in on the tank and view the damage clearly. However, since there was no reference object in the image, the engineers could not determine the scale of the damage.
In photographic situations similar to this, an object, such as a ruler, is placed within the field of view. This allows a person to look at a photograph and have a visual indication of the scale of the objects in it. In the External Tank situation, however, this procedure was not possible.
The innovation consists of a tool that attaches directly to a camera or charge coupled device using a standard screw. Two lasers fitted to the device provide parallel beams that are set 1 inch apart. These lasers enable the device to project a pattern into the field of view. When a photograph is taken, the image of the laser pattern appears, along with the image of the object under investigation, allowing the viewer quantifiable information as to the size of the object. The laser beams are accurate to approximately 200 feet.
WindowsÂ®-based software was developed to work with the scaling device tool. The software provides further techniques to measure objects in photographs and digital images. By using the software, any object in the image can be measured diagonally, vertically, and horizontally. The device and its software enable the user to determine two-dimensional measurements within a photograph.
Armor Holdings, Inc., a leading manufacturer of crime scene investigation accessories, signed a non-exclusive license with Kennedy for the rights to both the scaling device and its accompanying software. Based in Jacksonville, Florida, Armor Holdings provides the forensics industry with tools needed to perform a job efficiently and safely.
The small tool weighs approximately half a pound and is powered with one replaceable nickel-cadmium battery. The device can be easily turned on and off to allow a photographer to provide the valuable scaling information within a picture. The software program included in the package allows the user to import the photograph, benchmark the two laser dots, and provide scale to the photograph. The user can then apply a measuring component in the program to determine the distances or size of items within the photograph.