## Holography demo with real data¶

We'll start by importing the usual packages

The data from our microscope is in the proprietary .dm3 format from Gatan, the maker of the microscope. Usually this would be opened in something like Gatan Digital Micrograph, but luckily the OpenNCEM project helps us open it in Python (look here if using Matlab)

There is a wealth of metadata available about the microscope conditions embedded in the .dm3 files, but the most relevant to us is simply the scale, i.e. how many nanometers does each pixel correspond to in the image?

## Select sideband and do inverse transform¶

In the fourier transformed image we see the two distinct sidebands. fftshift is used to center the main peak in the image, as it would otherwise be split in the corners.