Of course, but even if you take all the photos whilst flaccid, so long as the conditions are the same, the comparisons remains the same.
My wife has been married twice before. When I got up the courage to ask her how my size compared with her other husbands, she tried to hedge for a while, then finally admitted that the first one was thicker, and the second one was longer. She tried to console me saying that I was "just right". But she has also fucked with lots of other guys along the way and has admitted to having been fucked by a few guys with monstor-sized pricks. As for me, I like to know that my wife has had the joy of being fucked by guys with really big dicks, and that there are some guys out there somewhere with really good memories of having fucked the pussy that is now my wife.