I have done that and built a 1:200 of the Rhodesia Castle with just photos. But I found the experience a bit unnerving, becasue i could never know if what i was building as in the least bit accurate. With plans, you have a good beginning, (hopefully) then i back it up with photos. Like I did with a recent SS Canberra, where I found some outstainding images on the web. One of my better attempts, i think.