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Once you have created the structure, it is advisable to inspect and (if appropriate) edit it by hand to ensure there are no errors. To do this, click "Edit Structure." You will be presented with a window that looks like the following: 
The first column is an index number in the FIRE structure, used for bookkeeping. The second and third columns show the fits file and object name as determined by matching with teh catalog, or, failing a match, form the OBJECT field in the header. The third column shows how firehose has classified the frame. All files classified as SCIENCE frames are tagged with an object ID, and grouped with telluric and arc calibrators, shown in the rightmost fields. Actual telluric frames are paired with an arc image.
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