Mine came the other day but I haven't had a chance to use it or the exposure calculator that was included. I'm in the process of assembling the calculator backed by plastic. The angle of view is 97 degrees. I printed a 97 degree template on clear (Pictorico) film and mounted it on plastic that can slide on to the camera. It's probably not comparable to a viewfinder but may be helpful. If anyone has other suggestions I'd like to hear them.
Thanks in advance.