LITE Images and Photographs
Each orbit page displays scaled color-modulated,
altitude-time plots of the daytime LITE (background subtracted) signal profiles for the 532 nm wavelength.
By clicking-on the scaled images, a new image page is displayed with a full size color-modulated plot (includes annotated
horizontal and vertical axis) and small LITE photographs. Larger JPEG images of the LITE camera photographs
may be obtained by clicking-on the small photographs.
The small LITE camera photographs displayed with the LITE color-modulated plots have been cropped, scaled,
and rotated in a direction which closely approximates the inertial velocity vector.
LITE daytime measurements were made during the ascending node portion of each orbit and the Shuttle
groundtrack extends from left to right across the center of each small LITE camera photograph. The overlay between
successive frames has not been cropped and
the user must visually align the photographs to see the continuation of cloud and surface observations.
NOTES for using the large JPEG images:
- The only annotation on the large JPEG images is the time in GMT. It is specified by DDHHMMSS, where DD is the last two
digits for the day of year, HH is the hour, MM are minutes, and SS are seconds.
The LITE camera photographs are available for days 252 through 262. The user must add 200 to DD to determine
the day of the year.
- The Shuttle orientation varied with every orbit and the large JPEG images must be rotated before they can be
aligned as a continuous photographic image along the LITE groundtrack. An explanation of how to orient the
LITE camera photographs is presented below.
- The orbit, latitude, longitude, and rotation of the JPEG image must be obtained from the documentation provided with the
small LITE camera photographs.
LITE Camera Description
The LITE camera is a modified half-frame 35 mm camera originally used for aerial reconnaissance. It was used to
photograph the Earth's surface and cloud cover during the daylight portions of orbits when lidar data were
acquired. A 25 mm focal length lens was used, giving a coverage of 200 X 200 km2. The time interval between
photographs is approximately 21 seconds, giving roughly 20% overlap between successive frames. A GMT time stamp
recorded on each frame was used to determine the latitude and longitude on the surface of the Earth that
corresponds to the center of each frame.
How to Orient the JPEG Images to Produce a Continuous Photographic Image Along the LITE Groundtrack
- Obtain the rotation angle listed with the small LITE camera photographs on the image pages.
- With JPEG image in vertical position (annotation along bottom), rotate around the JPEG image center,
in a clockwise directon, the number of degrees specified by the rotation angle.
- Align consecutive JPEG images by matching cloud or surface patterns.
- Merge the JPEG images to eliminate the 20% overlap between successive frames.