I have an IR image (IR band 1, red band 2) as a GRID file. I need to create a polygon layer of the irrigated lawn areas from this image. Having only a basic knowledge of raster processing, I have been using this "how to" page (click link) to try and do it. I used the Image Analysis tools in ArcMap 10 to create an NDVI from the image, and then exported that (right-click NDVI layer, select Data > Export Data) to an IMAGINE image file, per the instructions. That creates the .img file I need (after three hours of processing), but places the raster about 500 miles to the south west of the file it's exported from and covering a smaller area than the original. It says it's the same projection as the original and the NDVI. I tried defining the projection again and also verified the data frame's projection, as well as re-exporting the NDVI raster several times. I'm not sure what I'm doing wrong.
I'd like to know if anyone has any suggestions on what to do to get my rasters to line up so I can continue with the tutorial specified above.
I'd also like to know if anyone has a better approach to gleaning the lawn areas from my IR image and creating a polygon layer, rather than that tutorial I found.
Thank you for any assistance you can provide. I attached screenshots of my IR, exported map layer and projection info.
Before going too much further, make sure that your dataframe is set to the correct projection. Also, and this is important, clip out a small bit of imagery to do a test run.
