I have a picture of a hexagonally close-packed lattice and I took the FFT of the image using ImageJ. Below are the results. I expected the FFT to also be a lattice with reciprocal lattice spacing, I can see the lattice spacing, but I also see a large ring. Does this ring have significance?
I have some background knowledge of how Fourier Transforms work but I have little experience with them in practice so I'm not familiar with the different types of artifacts.