Original factory info: Canon Camera Museum
Overview: Rangefinder camera, 1959. Production was approximately 87,000. "P" stands for "Popular." According to Dechert, versions with a black ASA dial are built on a proprietary frame; color dial models are built on a common chassis with the Canon VI-L. I'll take his word for that. I think this is the most elegant rangefinder body ever made - heavy brass construction, luxurious chrome, glossy blackwork,, clean lines (including a recessed rewind lever). In terms of overall concept, this camera is similar to the current Voigtlander Bessa-R, but at the time it came out, it was in a somewhat higher price-point. This is becoming one of the most sought-after Canon bodies.
Viewfinder: Camera has three sets of framelines in its coated 1:1 finder: 35mm, 50mm and 100mm, all visible all the time. These are reflected, not projected as they are on the Leica M cameras and the Canon 7 (the difference is that the 7 and Leica M cameras light up the framelines using a separate window). The 35mm frameline is hard to see with glasses but better than nothing. Framelines move with the focused distance to correct for parallax. Rangefinder spot is round and yellow (uses a gold beamsplitter) and on a good example will read 2 EV brighter than the finder field. Rangefinder/viewfinder mechanism is unique to this model - basic RF mechanism is drawn from from the Leica III but is combined with the viewfinder image. The eyepiece is thankfully smooth and does not harm your glasses. No diopter help is available.
Where the hell is the camera? Oh, yes, on the kitchen table!
Rangefinder and limitations: Like most Canon RF cameras, the P has a 41mm baselength. Previous models such as the IVSB, the V and the VI had three position finders utilizing a reversible galilean finder providing 0.7 magnification for 35mm (no framelines); 1.0x magnification for 50 and 100mm (reflected framelines); and a round 1.5x image (RF or Mg setting) for telephoto focusing. Although the P does not have the 1.5x setting, its RF is sufficiently accurate to focus the 50/1.2, 85/2, a 105/2.5 and 135/3.5. The P also dropped auto-parallax compensation for Canon accessory finders. This is no great loss.
Odd design feature: This camera, like the L, the V, and the VI before it, is a swing-back design. Leica has never adopted the philosophy that the back should just open. The Canon cameras are considerably easier to load. Notably, the Canon flange design requires only one lightseal - a 2x2mm spot on the back door near the hinge (inside the door).
Odd design limitations: This camera is incompatible with the Kobalux 21/2.8 and 28/3.5; the Soviet Jupiter-12 35/2.8, and the Zeiss Biogon 21 (unless you take off the protective "ears." This is due to the use of light baffles (wholly absent in Leica's cameras). Do not use with collapsible lenses (they can damage the insides). Also, if you move the wind/rewind collar to rewind while the camera is cocked (at the end of a roll) it can fire.
Odd design limitations, nothing! Odd ads, too...
Shutter: The shutter is a plastic-coated ultrathin stainless-steel foil which is functionally identical to the rubberized cloth in the Leica cameras. The difference is that this foil does not burn when you point the lens at the sun. It does, however, wrinkle if you stick a finger in it while loading (this does not affect function). Noise level is equivalent to an M3. These shutters age infinitely better than Leica M shutters do, probably as a result of using synthetic lubricants. Flash synch is 1/60 ("X" on shutter speed dial), and if you use FP bulbs, it will synch at any speed. PC terminal is on the side and fits both regular and snap-lock type PC cords. It also has a surrounding bayonet that can be used to lock on an old Canon fan-flash.
In Operation: This is a very smooth, very luxurious camera, with the biggest treat in the butter-smooth wind (using a very ergonomically-designed lever - shorter and easier to operate than on the M3) and crisp shutter response. Although it may have been marketed as a low-cost sister to the VI-L, it is definitely a cut above the 7 in solidity and refinement and easily beats its modern clone the Bessa in overall feel and balance (though lacking the Bessa's meter, higher shutter speed, and 75mm framlines).
Balance/feel: Although this camera is almost the size of an M3, it is much lighter and feels much smaller in the land. One thing to be aware of is balance. Most modern lenses are aluminum. The P is a relatively heavy brass body. As a result, with the Jupiter 50/1.5, for example (aluminum), the camera tends to tilt back. It balances ok, with the Canon 50/1.8 (that it typically came with) and the Jupiter-9 85/2. It balances well with the Canon 50/1.5 and the Nikkor 50/1.4. It is front heavy with the Nikkor 105. This is in stark contrast to the more modern Bessa-R, which so light that it is front-heavy with everything except a Soviet 50!
Accessories: Canon didn't really make many. The big thing to get is at least the bottom half of a case (brown). The original Canon P strap is nothing to write home about, and most are in sufficiently poor shape that you shouldn't even think of using them to hold the camera. You can also use the bottom of a Canon 7 case. If you do extensive tripod work, you should locate a "Camera Holder," which is a metal surround that centers the socket and provides a bubble level.
Bottom Line: If the M3 is your breadwinner Chevy, the P is your MG weekend car.