Is it okay to digitize/modify figures "reproduced from reference" in a thesis? I am a student starting preparations for a masters thesis in a U.S. research university (on a physics/materials science topic).  I have seen digital versions of past MS theses and PhD dissertations from my university, and many use figures from textbooks and/or journal articles with a line "reproduced from reference[##]" and the reference given in their bibliography.  I believe that they're counting on "fair use" rather than actually contacting the original copyright holders according to the ideas given from this MIT page and this Ac.SE page.  When reproduced this way all the figures I have seen are copied exactly as from the original document (or as close to exactly as a print-screen button will get you), but pixelation issues (from enlarging raster images) as well as inconsistent plot styles can make this appear rather sloppy, hence my more specific question:


Would digitizing a figure rather than photocopying it still constitute "fair use"?


By digitizing I mean converting a raster-image plot to x,y data and then using software to make a vector-image from that data.
Assume the data is being reproduced faithfully (i.e. data points are not being altered to sway the interpretation of the data one way or another.)
Assume the phrase "reproduced from reference[##]" is still used, or even a more descriptive phrase such as "reproduced from reference[##] and digitized for clarity".



I feel like this is still in the spirit of fair use, but still unsure whether the whole digitization process might change the legality beyond the scope of the "four-factor test" from the MIT link.
Probably, but just recall that fair use is a defense in court against being sued not a blanket permission. It's always easier to ask the publisher for permission. I don't think that tracing over a scan of the figure changes the fair use analysis at all, but you should really ask your attorney. You should always reference the source of your images whether you are tracing over it or using the scan.