Which is Larger?

It is always interesting how what you paint on a canvas can make it look bigger or smaller.  I haven't quite figured it out, but sometimes a painting with lots of detail can look larger than it really is; and vice versa, a large painting with little detail looks smaller, especially in reproduction.

I was recently putting an undercoating on a canvas, and left it sitting side by side with an unpainted  canvas of exactly the same size.  Here they are:

Do they look the same size, or does one look larger than the other?