Very glad I was able to acquire this Demi EE17. I immediately put a new Wein MRB625 battery and film in it (Ferrania P33) and began an exhaustive 72-exposure test. I tried all shutter speeds and apertures manually, all lighting conditions in auto-exposure mode, a series of minimum-focus tests, and a flash shot with the Canon J-3 unit and an AG-1 bulb. It worked perfectly as described! (Minimum focus turns out to be 2 feet 6 inches from focal plane.)
There is a filter factor adjustment lever on the lens barrel that goes from 1x to 2x to 4x, increasing exposure 1 or 2 stops to compensate for the light reduction caused by a filter. This could also be used when the subject is very strongly backlit and there is not enough fill lighting to compensate. I didn't use any filters on any of that first roll, so I kept the lever at 1x.
For the test roll, I ignored the zone-focus indicator in the viewfinder. This shows a needle moving behind three images: a portrait, a group of 3 people, and a mountain. As you move the focus lever, the needle indicates roughly how far away the lens is focused. This allows the photographer to quickly focus, check exposure correctness in Auto mode, and press the shutter release button. But I chose not to do zone-focus and instead estimated (or measured) subject distances and set focus using the focus scale on the lens barrel. After developing the film, I see that because of the 30mm lens' depth of field - even at maximum aperture of f/1.7 - I could have used zone-focus and gotten good results whenever stopped down to f/2.8 or smaller.
The lens has very good contrast and crispness - even wide open at f/1.7. I'm very impressed by its image quality, and it is fast enough to be used in relatively dim light. There seems to be very little lens flare from bright lights in backgrounds or from specular reflections off shiny objects. A point worth noting is that because of the lens' relatively short 30mm focal length, it is possible to hand-hold the camera at 1/30 quite easily. The rule of thumb for casual hand-holding without camera-motion blur is "the inverse of the focal length," which is 1/30th of a second for this lens. With practice and a little bracing of elbows on a table or when sitting down and after exhaling, you could probably hand--hold this camera at its longest timed shutter speed of 1/8 and still get decent results. (There is also a B setting for use with a tripod - and also a built-in self-timer.)
The meter is accurate within its range from EV4.5 to EV17. This roughly translates to 1/8 sec at f/2 to 1/500 sec at f/16 with 100 ASA film. It seems like the Canon engineers kept the meter's range in mind when they designed the camera's shutter mechanism, because the shutter speeds range from 1/8 to 1/500.
Canon made the Demi EE17 model from May 1966 to April 1967. I still have my parents' EE17, which has a lower serial number than the one I purchased, so I'm assuming theirs was made in 1966. Something in the winding mechanism stopped working, likely from decades of disuse. The one I purchased has a much higher serial number, so it was probably made late in the production run. I'll call mine a 1967.
So why did I buy a half-frame camera from 60 years ago? Because I still remember using it on one of our trips to Hawaii, probably in 1967, and taking a photo that hooked me on photography. It was just a vertical black-and-white shot of the roots of a banyan tree in a park somewhere. But there was something about the shot - a combination of exposure, film grain, depth of field, and composition - that made me want to keep taking pictures. So yes, there's some sentimental value at play here. (And come to think of it, the 4-perforation 24mm x 18mm frame size is exactly the same as used during the silent era of motion pictures.)
Incidentally, the focus levers of mine and my parents' have the same level of resistance. I remember that it was always like that. So if you come upon another one and add it to the Camera West stable, don't worry if the focus lever requires about as much effort as the shutter speed collar.
(I've attached shots I took after leaving Camera West with the Demi EE17. Maiden Lane, Heart at Union Square, Bourbon Bar at the St. Francis, Chandelier at the St. Francis.)