Some folks at the pirateship and I used a Roscoe 2008 filter which had not been very well white balanced to take some aerial photos of our building and neighborhood, but I found that the resulting NDVI images (made with Ned Horning's Photo Monitoring plugin) didn't work very well -- the trees and lawn did not display with high NDVI values. What's the problem? Can I do a better post-white-balancing to recover useful data?
Was the Roscoe 2008 not as good as the 2007? I notice that Chris F did not have one in his exhaustive comparative search for filters, in this research note. But the filter looks visibly similar... what do you think? I can do a spectrometer scan of both for comparison.
4 Comments
Jeff, do you have an image of the lut you used? You can open a lut in Fiji by file/open.
Is this a question? Click here to post it to the Questions page.
Reply to this comment...
Log in to comment
The Rosco 2008 should be one of the best filters for making NDVI because it blocks all the red light better than others. It has only 40% of the overall transmission of the 2007, so exposures will have to compensate by more than one f/stop. It blocks a lot of the green light too, so false color Infrared (NBG) might be harder.
The first thing I would do is to make a floating point NDVI image, open it in Fiji, and apply the lut of choice to it. That might look different from the color NDVI produced by the plugin.
Is this a question? Click here to post it to the Questions page.
Reply to this comment...
Log in to comment