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Revised 15 December 2002. The cropped images have been replaced  with the full images, the enhancements are new, and a file for printing a letter sized image is available for each image. The originals are in the public domain.

Summary. NASA has selected 500 of the most striking images taken from the space shuttles for a special collection, Earth from Space. Several images of Flathead Lake and the territory around it are included in this collection. Below, I present several images that I enhanced using Adobe Photoshop.

Technical details. Each space shuttle mission produces 2000 to 5000 still photographs, using 35mm, 2.25-inch, and 5-inch film formats, as well as digital cameras. After a mission is completed, the films are developed, digitized at low resolution, and cataloged. E-6 color transparency film is used, although some 35mm images are made on color negative film. The best images resolve a surprising amount of detail, but the quality is not as good as what can be obtained from a high flying aircraft equipped with high quality cameras, or from an unmanned imaging satellite.

The Earth from Space images are available in two sizes, low resolution (640 x 640 pixels) and high resolution (3,000 to 5,000 pixels square), and can be downloaded as JPEG compressed, 24-bit RGB files. The low resolution files typically are 200K, expanding to a megabyte. The high resolution files range from 5 to 15 megabytes, expanding to 40 to 75 megabytes. In many of NASA's scans, terrestrial objects are low in contrast, have a bluish cast, and greatly benefit from contrast and color enhancement.

Viewing tip. To view the images, click on the thumbnail or the image number.

Printing note. I use Epson's 6-color photographic quality inkjet printers, usually the 820. My standard file resolution is 180 pixels per inch. My standard printer resolution is 1440 pixels per inch. I usually print on Epson's Premium Glossy paper. Epson's standard photo paper also works well. An ICC profile -- Adobe RGB -- is embedded in the larger files for those of you who have ColorSync (Mac) or ICM (Windows) color management software.

Image STS51B-038-0102. Taken on 30 April 1985 from the Challenger, on Mission 51B, using a 250mm lens (equivalent to a 135mm lens on a 35mm camera). North is toward the upper left corner. The camera angle is near vertical.

The image on the left is the original from 1997. Note the bluish cast and low contrast. The image on the right is the one that NASA supplies today.

Image STS51B-038-0102, enhanced. The bluish cast is gone and there is more contrast. Note the differences in color in Flathead Lake, which correspond to depth. Shallow Polson Bay is markedly lighter than the rest of the lake.

The enhancement technique involves a combination of masking, histogram stretching, selective equalization, some color correction, and sharpening.

The enhanced image has sufficient resolution to be printed on letter sized paper.

Image STS068-170-060. Taken in late September, 1994, from the shuttle Endeavour, on Mission 68, using a 250mm lens. North is toward the bottom right corner. The camera tilt is low oblique and the altitude is 116 nautical miles.

This is the scan as provided by NASA. Note the bluish cast and low contrast.

Image STS068-170-060, enhanced. Further enhancements of the Swan Valley (not shown here) reveal the extent of land modification.

Image STS045-152-054, enhanced. Made on 28 March 1992 from the shuttle Atlantis, on Mission 45, using a 250mm lens. North is toward the upper left corner. The camera tilt is low oblique, and the altitude is 164 nautical miles. The high resolution version of this image expands to 59.4 megs.

In this image, both the Flathead and the Rocky Mountain Front are visible, as are the Mission and Jocko Valleys. Far left, original image.

Image ST028-90-018. Made in early August, 1989, from the shuttle Columbia, on Mission 28 (the fourth Department of Defense mission), using a 250mm lens. North is toward the upper right corner. The camera tilt is low oblique, and the altitude is 162 nautical miles.

Far left, the scan provided by NASA in 1997. Note the bluish cast and low contrast. Left, the scan provided in 2002 is dark, but not as blue, and has been rotated 90 degrees counterclockwise.

Image STS028-074-070. Made in early August, 1989, from the shuttle Columbia, on Mission 28 (the fourth Department of Defense mission), using a 250mm lens. North is pretty much straight up. The camera angle is low oblique and a 250mm lens was employed. Flathead Lake is bottom, middle. I'm indebted to Helena based GIS expert Ed Madej for steering me to this image.

The high resolution version of this images is 5000+ pixels square and expands to 80 megabytes.