Pedro Dylan, you sound like a scientist in the mankig! Light and shadows and your vision are sure interesting to examine. Sometimes what seems to be so normal in everyday life can actually have a lot of features to investigate. When you are done mankig your binoculars, you might want to try mankig a periscope. You need a long box or tube (like for wrapping paper) and two little mirrors that will fit inside. Then you can see around corners!