How to prepare the two photos
Use one front-facing photo per person, taken in similar lighting. If one photo is warm indoor light and the other is blue outdoor shade, the model has to reconcile two different skin tones, which makes identity matching harder. A pair of daylight photos is the safest starting point.
Crop each photo to the person, with the face and shoulders visible. Avoid photos where the two people are already together but one face is turned away. The model needs a clear view of each face to preserve it.
