Hi everyone, mediocre GIS user here. I have some Ortho imagery files (jpeg2000) that I am trying to merge into one file and am having issues with this. I was able to merge three images from one year of data images together correctly using the Mosaic tool, but I have six images from another year that will not work. I used to Mosaic tool on these as well, and the process was supposedly successful, but now the image that I used as the Target Raster is much larger in size than it was before, but it still looks the same on the map as it did before I used the tool. I looked up different methods of how to perform this function and read about the Merge Raster tool, which by its name seems exactly like what I want, but it required opening the attribute table of the image, which I was unable to do (greyed out). I also tried Mosaic to New Raster, which came back unsuccessful stating that the Spatial Reference needs to be the same for the Target Raster and the Input Rasters. I used the same coordinate system and band numbers for the Target Raster, so I am not sure why I got this message. I tried Mosaic to New Raster again and this time it was successful, even though I changed nothing. Could a more knowledgeable person please explain why this happened and give advice on a more consistent method of achieving results? Thank you.