I’m a photographer. I like to use a viewfinder to frame and compose a picture. Today I tried using a viewfinder made out of a 3×5 card clipped to my Moleskine pocket notebook. I first drew a frame the same size as the viewfinder and added guide marks on the edges using red erasable ink. I then sighted through the viewfinder and sketched the major shapes again using the red erasable ink. Then I used black ink to finish drawing and shading the trees. Later I erased the red guide lines with a hair dryer, and scanned the image.
This worked reasonably well. Next I want to tape the viewfinder so it hinges out to the side from inside the front cover.