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Rephrase NDVI index Formula


New member
May 19, 2015
Dear all,

Im currently doing my research in NDVI index.

As some of you might know the NDVI forumula is based as following


NIR = the ratio of reflected light/incomming light near infrared (NIRref / NIRin)
VIS = the ratio of reflected light / incomming light Visible (VISref/VISin)

about a year ago i mathematically constructed the following formula

NDVI = ((VISin/NIRin) * (NIR-VIS)) / ((VISin/NIRin) *(NIR+VIS) )

I know this is mathematically correct. however ofcours i lost my notes.
and i cannot find the way is solved it last time.

Can anyone help me with this?

Thanks in advanced!

Ralf Smit