An alternative to printing out the QR codes on paper is to display them on a mobile device and photograph the QR code on the mobile device.
Doing it this way you 1) Must have subject contact (email) data and 2) the subject won't have the paper to scan to view the photos (but will be sent the passcode when you email the contacts when the photos are ready).
To get to the mobile site it is the link to your admin then /qr. Example, if the link to your admin is testsite.com/sy-admin then the link to your QR mobile site is testsite.com/sy-admin/qr
You can also find the link by creating a QR passcode gallery, clicking the QR Passcodes tab and toward the bottom of the page will be a link to the mobile site.
Once you pull up the mobile site, click on List Entries next to the job. You will see a list of entries. Click on the subject's entry to pull up their QR code. Photograph that QR code then photograph the subject.