I was caught off guard, so I told her what lens and camera I used to make the photo. As I was speaking another lady came over and the discussion turned into a conversation about what cameras they both used as casual photographers. A few hours later I realized the opportunity I'd missed.

I should have explained the exposure adjustments I had to make from the original file. I should have told her about the time I spent making variations on the image. I should have told her about the refinements I made before I felt it was good enough to make my first test print. Then I should have let her know about the minor adjustments I needed to make because something wasn't quite right with the way the print looked under different lighting conditions. 

I should have said all of those things, but I didn't.

So from now on If someone says to me "That's beautiful. What lens did you use?" I'll now be able to explain a bit more of my process than I have in the past.