Filming with the Bolex H - Text 4
Viewfinders
The H16 Reflex, introduced in 1956, is undoubtedly the most famous model in the series. Its novelty consists in a reflex viewfinder through which one sees directly the image being recorded on the film stock via a system of prisms, including a semi-reflective prism located between the lens and the exposure window. This means that the viewfinder deflects part of the light normally available to the image. This is detrimental in principle, and even more so in that one most take this absorption into account in the graduation of lenses and light meters. Therefore, there are special photoelectric cells and lenses for the Bolex H16 Reflex, unless one corrects the exposure oneself using tables included in the user’s guide. This solution to the problem of the reflex viewfinder, making it possible to frame the shot directly through the lens, and thus to make the eyepiece a precise frame showing how the film stock will be exposed, was not the only one possible. In fact the most widely adopted solution since the Arriflex camera of 1937 consists in attaching a mirror at 45° to the rotating blade of the shutter. In this way, the image is transmitted to the eyepiece when the shutter is closed and impressed on the film stock when the shutter is open. Professional cameras are all equipped with such a system, but so too for example is the Beaulieu R16, a competitor of the Bolex H16 on the European market which was introduced in the late 1950s and has many points in common with its cousin from the canton of Vaud.
To understand the importance of the innovation introduced by the reflex viewfinder, we must first complicate the idea that it is a means for doing away with parallax when framing. In fact, previous H16 models were equipped with two viewfinders. The so-called “clear” viewfinder can occupy two positions on the camera. The first is situated on top, a position advised for transporting the camera but which can also be used for filming: “it is perfectly adequate for ordinary shots from a distance of more than 2 m,” says the user’s manual. The other position is when the viewfinder is attached to the door of the camera, at the height of the exposure window, right beside the medium lens in the turret. It did not take long for these viewfinders, sometimes called “octameters,” to be equipped with adjustment levers and thumbwheels, the former for adapting to the focal length of the lens and the latter for showing the focal distance. These two thumbwheels make it possible, in the user’s guide’s description, to correct the parallax and to present to the eye a “rigorously precise” and very luminous frame, much more so than the reflex viewfinder.
