Toronto. Continuing yesterday’s theme on hand held exposure meters (thanks George), this advertisement from Popular Photography’s April 1948 issue shows the famous Weston Master II meter. I bought in less than a decade later with the Master III. Both the II and III had dual scales and used a bakelite disk to switch from bright light to dimmer light.
The meters of that era used light sensitive selenium cells which generated a current when exposed to light – no battery required. Earlier Weston meters used a similar dial. The Master II and later Master III showed minor refinements to the dial. By the time the III was released the famous Weston dial read in ASA numbers, not Weston numbers.
The meter gave excellent results in daylight but sensitivity all but disappeared indoors or at night when a means to determine the correct exposure is most important.
The days of hand held meters were coming to an end. Briefly coupled on-camera meters became common place, then meters were built into cameras. Today, the concept of a separately adjusted meter is obsolete. Cameras and smart phones automatically adjust for the amount of light, shifting speed, aperture, and ISO value. And today’s ISO values were unheard of just a few decades ago, as was optical stabilizing circuitry.