Recording Recommendations

I am advising a lab that would like to detect and study the emotions exhibited during cognitive behavioral therapy sessions. They would like to collect video that is well suited to Affectiva (while being as inconspicuous as possible). We hope to record both the therapist and patient (and sometimes the patient’s parents sitting next to them). The therapist and patient usually sit across a table from each other, but they sometimes move around. A fair amount of time is spent writing and drawing, so the faces are often pointed down.

I see here that Affectiva recommends:

  1. positioning the camera within +/-25 deg of head-on (I assume this is horizontal)
  2. avoiding backlighting that might make the average face pixel brightness fall below 30/255

Are there any known limits on vertical angle? Are there any other guidelines or suggestions I can provide as we decide how to collect data? Are there any camera setups that people have successfully used for similar situations in the past?

Thank you for any suggestions you might have!