Time of day, season, weather, flap setting, any one of which might have a noticeable effect. Was the model 'over' powered, 'under' powered. How do relative speeds affect flight characteristics between a model and full size? E.g., a full sized F-18 rotates, and lifts off, at what speed and lands, compared to a model. Perhaps, asked another way is there a mathematical ratio? I guess we need a full size pilots input, and radar readings at model speeds for accurate info. The obvious problem with a photo, the split second in time-the pilot could have pulled/shoved the stick full aft or forward a moment later. Another question, the incidence of the wing to ground in the roll, how near to full size is the 'average' model, thus its effect.