please read this paragraph:
"Satisfied with your composition, you back away from the
tripod to make sure your body doesn’t wiggle the camera during the exposure. While
your eye blocked the viewfinder, your backing away now allows ambient light to enter
the viewfinder. The additional light added to the ambient light entering the lens and the
camera responds to increased light by reducing the exposure. You are perplexed by the
butterfly being so dreadfully underexposed."
can someone paraphrase that.. is it reaaly saying by vewing through viewfinder you practically decreases the light and exposure by blocking the stary light entering from visor?