Leica has been producing rangefinder cameras and lenses since the early 1900s.
Best known for its line of "M" rangefinders and accompanying lenses, Leica is a recognized leader in quality photography equipment. Rangefinder lenses are slightly different from their SLR counterparts. With an SLR, a photographer views the scene through the lens, while with a rangefinder the photographer looks through a viewfinder that has lines to replicate the field of view of the lens.
Instructions
1. Hold the Leica camera up to your eye and look through the viewfinder. Position your left thumb under the lens into the grooved focusing tab. On smaller Leica lenses there is a grooved tab designed for the photographer's thumb that can be used to focus the lens. On larger Leica lenses the focusing ring resembles those found on SLR lenses.
2. Move your hand toward the front of the lens, and turn the aperture ring to change the lens' aperture to the required setting for correct exposure. The aperture ring on Leica lenses is always at the front of the lens, whereas on manual-focus SLR lenses it is at the rear of the lens, close to the mounting ring.
3. Observe the depth of field guide to confirm your lens is in focus. Focusing with a rangefinder takes a little practice and, when first starting out, you may find it more difficult compared to SLR focusing. The depth of field guide is a series of numbers representing the lens aperture. The numbers appear in sequence on the left and right side of a center dot. If your aperture is f8, find the number eight on the left side of the center dot and the focusing distance that is on the focusing ring just in front of the guide. Do the same on the right side of the center dot. The range between these two focusing distances will be in focus when the aperture is set at f8.
Tags: Leica lenses, side center, aperture ring, depth field, depth field guide, field guide