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hey people, i have the trouble with CI index in Erdas, when i am useing the image from landsat 5 tm with atmospheric correction it gives me the whole white picture in the results,

the formula CI=1-((red-blue)/(red+blue)) also i tryed to change R band with NIR, but......does not work at all

when i tryed to insert in the model the bands seperately the reslusts are the same, just white pic,

can anyone help with this type of issue?

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I don't use ERDAS, but am guessing it might expect values in the range 0..255 or the range 0..1 rather than 0..2. You might therefore need to multiply your CI by 128 or by 1/2 in order to view the result.

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