CHANGING THE FOCUSING SCREEN-continued

Focusing Screen Selector Guide

Typ e A. L

Type A: Matte Fresnel field with 3mmq>.circul"r split-image rangefinder spot and 12mm¢circle. Rapid and accurate focusing. Excellent for general

 

photogra phy.

 

 

Type L: Same as Type A screen but witll split-image

 

rangefindCI line

at a 45 ° anglc . Bcst for subjects

 

with horilontal

lines.

 

Type B: Matte Fresnel field with 12mm¢ fine-

 

ground matte focusing spot in the center. Good for

 

general photography, especially with long lenses.

D

Ty pe C: Fine-ground matte field with 4mm¢clear

spot and cross hair. For photomicrography I astra-

photography and other high-magnification applica-

tions, and for parallax focusing on aerial images.

Type 0 : Overall fine-ground matte field. For specialized close-up photography and for use with long lenses.

Type H: Clear Fresnel field with microprism focusing patter n over the entire screen area . Permits rapid focusing on any part of the screen with optimum edge-to-edge brightness in poor light. Available in four models (1-1 ' -1-1 4) corresponding to particular focal length lenses.

Ty pe J : Matte Fresnel field with central microprism focusing spot and 12mm</> circle. Good for gene ral photography.

Type K: Combination of Type A and J screens. Matte Fresnel field with 3mm¢ spli t-image range- finder spot surrounded by 1mm-wide microprism doughnut. Rapid and accurate focusing for subjects with both straight lines and ill-defined con- tours. Suitable for general photography.

Type M: Fine ground Fresnel field with 5.5mm</> clear spot and double cross hair for use in parallax focusing on aeria l image, plus millimeter scales for calculation of individual magnification of objects or for measuring objects. Brilliant image in dim light. Suitable for close-ups, photomicrography and other high-magnification applications.

Ty pe E: Malle Fresnel field with 12mmrJ> fine- ground matte spot and etched horizontal and veni-' cal lines. Ideal for architectural photography.

Type P : Same as Type K but with split-image rangefinder line at a 45 0 angle and etched horizontal and vertical lines as an aid to composition. Rapid and accurate focusing for subject wi th horizontal or vertical lines or ill-defined con Lours. Suitable for general photography .

Ty pe G: Clear Fresnel field with extra-bright 12· mm</> microprism focusing spot for viewing and focusing in poor light. Four models (Gl-G4) are available corresponding to specific focal length lenses. Depth of field cannOI be observed.

Type R : Same as Type A but with rangefinder prisms of sloping surfaces at a smaller angle and horizontal and vertical lines to aid proper composi- tion. Wor ks best with lenses having maximum aperture of from f/3.5 to f/5.6

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