NDVI rannge not between -1 and 1

TXPE

I have two different data sets.  Both are collected with two Canon S100 cameras.  One camera is RGB and the other is NIR-GB.

The first data set I ran several months ago, and as I recall, everything went fine and the raster calculation resulted with a NDVI range of -1 to 1 as expected.

My second data set I'm working with now results in a -3.3 to 3.3 range.  I've looked at the various parameters for both and they seem to match up.  I can't figure out why I'm not getting the -1 to 1 range as expected.  I'm hoping I've overlooked something simple.

Anyone have any suggestions?

Thanks,
Doug

TXPE

I figured it out.  The display was showing in ft, not meters.  Changing display to meters results in a -1 to 1 range.