Narcotics research, rehabilitation, and treatment. Hearings, Ninety ...

Narcotics research, rehabilitation, and treatment. Hearings, Ninety ... Narcotics research, rehabilitation, and treatment. Hearings, Ninety ...

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84Figure 1infrared Ektachrome film with a spectral response between 0.510 and0.890 microns. The dark dotted patches are crops. Across the bottom isseen a section in which the amount of dotted area, and consequently thevigor of the vegetation, is markedly lower. That sharp line of demarkationis close to the Mexican border. A single color photograph like thisone contains limited useful information.The next figure (fig. 2) shows the same scene in three photos made atthe same time. The one on the upi^er left was taken with Pan X filmwith a green filter; the upjx^r right on Pan X with a red filter; and thelower photo on black and white film "sensitive to infrared radiation. Itis apparent that each photo produces different relative contrasts andenhances the images of some features over others.The next photos (fig. 3) demonstrate the different resi^nses thatsimilar crops will provide in relatively narrow spectral bands. The leftphoto, made with a blue filter, shows little difference between oats and

85Figure 2wheat. But the ones made with red and infrared filters show the distinctionquite clearly. So, in a simple case at least, we see that it isix)ssible to isolate crops in this way.In fact, it is possible to do a lot better than that. The next photos(fig. 4) show how two varieties of corn which can hardly be differentiatedat visible wavelengths (on the left) look quite different at infraredwavelengths.Mr. Perito. May the record reflect the lights being turned back onand we are continuing with Mr. Jaffe's statement.Chairman Peppek. Without objection, so ordered.You may proceed.Mr. Jaffe. What I have illustrated here are the mere fundamentalsof remote sensing of agriculture. These techniques have been advanced

85Figure 2wheat. But the ones made with red <strong>and</strong> infrared filters show the distinctionquite clearly. So, in a simple case at least, we see that it isix)ssible to isolate crops in this way.In fact, it is possible to do a lot better than that. The next photos(fig. 4) show how two varieties of corn which can hardly be differentiatedat visible wavelengths (on the left) look quite different at infraredwavelengths.Mr. Perito. May the record reflect the lights being turned back on<strong>and</strong> we are continuing with Mr. Jaffe's statement.Chairman Peppek. Without objection, so ordered.You may proceed.Mr. Jaffe. What I have illustrated here are the mere fundamentalsof remote sensing of agriculture. These techniques have been advanced

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