I extracted the hidden QR code from the image and adjusted the levels getting this image:
The quality of the QR code seem to be very bad (@CasperTheFriendlyCode do you have a better version of the image?). Online decoding tools don't work but an Android app returns the following text:
01000011+01111001+00100000+01100011+01101111+00100000+01100001+00100000+01100101+01100001+01110000+01110100+00100000+01111001+01100011+01101101+00101110+00100000+01110101+01110010+01110000+00100000+01111001+01100100+00101110+00100000+01010000+00101110+01111000+00101110+01101110+01101110+01100011+01110010+01100010+01110110+00100000+01000001+01101110+01111001+01100100+01110010+01100111+01101001+01100100+00100000+01111001+01100100+00101110+00100000+01000101+00101110+01100001+01111001+01100100+00100000+01001111+01111001+01100001+01110000+00100000+01100100+01100001+01101111+00100000+01111000+00101110+00101110+01100010+00100000+01100101+00101110+01101111+01111001+01110000+01110010+01100110+00101110+01100101+01110111+00100000+01000011+01101101+01101100+00101110+01110000+01100011+01100001+01101110+00100000+01111001+01110000+01110010+01110010+01101100+01101111+00100000+01100100+01100001+01101011+00101110+00100000+01100101+01110000+01100011+01101011+00101110+01100010+00100000+01111001+01100100+0
These are obviously ASCII codes in binary form, but something seems to be missing (maybe because of bad quality of the QR code). The present part can be translated to:
Cy co a eapt ycm. urp yd. P.x.nncrbv Anydrgid yd. E.ayd Oyap dao x..b e.oyprf.ew Cml.pcan yprrlo dak. epck.b yd
This is the place where the hint must be used. The professor used a Dvorak keyboard. Replacing the letters on the Dvorak keyboard with the corresponding letters on a Qwerty keyboard gives this:
It is a dark time for the Rebellion. Although the Death Star has been destroyed, Imperial troops have driven th
I'm stuck here because a part of the message seems to be missing.