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At this point, you may go back and identify more lines by hand and iterate on the 1D fit. With your working model of the wavelength map it is also possible to have the code attempt an auto-id of all lines from the line list, although in our experience this has been spotty. If you are satisfied with the final product type 'q' or click 'Done' to complete the wavelength fit. For completeness, we show below a zoomed-in version of the wavelength plot to illustrate the appearance of positively identified lines.
After you complete the 1D wavelength fit, the code projects this onto a 2D wavelength map, using information about the curvature of the slit image in detector coordinates. As a check, the code plots up an image of the slit illustrating the quality of the slit curvature fit: 