Nikon F25B manual Exposure Measurement

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EXPOSURE MEASUREMENT-continued

Eyepiece Shutter Operation

High-Contrast Lighting Situations

The camera's Photomic finder is fitted with an eyepiece shutter for special unmanned shooting situations (e.g., remote control, automated shooting with motor drive and aperture control unit) requiring protection against the entry of stray light through the viewfinder eyepiece. To close the shutter, simply turn the eyepiece shutter control 60° clockwise; as the shutter closes, the internal LEDs are deactivated and the external "correct exposure" indicator is switched on for metering operation from atop the finder. To set the camera for proper exposure using the external LED indicator, simply adjust the aper- ture ring and/or the shutter-speed selector until the LED just glows; once the LED comes on, the camera is set for correct exposure.

In addition to its use for low-light metering or for un- manned photography, the eyepiece shutter comes in handy to ensure correct exposure measurement in criti- cal shooting situations (e.g., photomicrography) or for protection against the entry of bright light into the view- finder during daylight shooting.

When there are substantial brightness differences be- tween the main subject and the background, unimpor- tant bright spots or dark spots can adversely influence the finder reading, and thus the final exposure. To pre- vent under- or overexposure of the main subject under these shooting cond itions, some corrective action must be taken to ensure proper exposure of the main subject. Fortunately, the finder's center-weighted TTL metering action simplifies adjustments, making for qu icker camera operation and more accurate final resu Its.

To compensate for an excessively bright or dark back- ground, target the main subject in the center of the fo- cusing screen wh ile performing metering; th is action en- sures that the main emphasis of the meter reading will be on the chosen subject. Then, after completing aper- ture and shutter speed adjustments, recompose to the desired picture composition and make the exposure without readjusting the camera controls. For example, when shooting landscapes, it is often advisable to aim the camera slightly downward during exposure measure- ment to eliminate the effects of a bright expanse of sky; without such compensation, the landscape may appear underexposed in the final print. Also, for backlit sub- jects, it may be necessary to move closer to the subject to ensure a proper reading.

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Contents Page Nomenclature Page Contents Foreword Preparation for USE Loading the Film Preparation for USE Prior to ShootingSetting the Film Speed Memo HolderSetting the Shutter Speed Operation of Camera ControlsFilm-Advance Lever Frame CounterOperation of Camera Controls Unloading Film Holding the Camera Shutter Release Operation Focusing Ou t of foc us Foc us Focusin G Depth of Field Depth-of-Field Preview ButtonDepth-of-Field Indicators Depth of FieldPage Exposure Measurement Page Exposure Measurement Page Exposure Measurement + 0 STOP-DOWN Exposure Measurement Page Exposure Compensation Adjustments Renex Exposure Compensation Adjustments Multiple Exposuresmirror Lockup Tl~ T-+ Flash SynchronizationReady -LIGHT Finder Illuminator Tips on Camera Care Page Changing the Lens Maximum Aperture Indicator 26-2.5Changing the Viewfinder Changing the Focusing Screen Changing the Focusing Screen Focusing Screen Selector Chart Accessories Lens Hoods FiltersEyepiece Correction Lenses Finder EyecupFEATURES/SPECIFICATIONS Nikon Warranty