Order tracing

This image shows two simulated flat-field exposures on the three new CRIRES+ detectors. On the top with an open slit, below with the decker that blocks two quarters of the slit. The white lines show the first result from the data reduction routine that tries to locate the orders on the detectors. Dashed is the overall polynomial fit to all pixels that are identified to belong to the same order, dotted lines are the fits to the upper and lower edges.