Exposure Evaluation
Digital Spot Metering
The camera control software includes two types of digital spot meters. The first is a “live” spot meter that displays information about the image as the cursor is moved within the preview area. Specific areas of the image can be metered at any time by moving the cursor to the area of interest in the preview image and reading the various displays. The second type of digital spot meter is a “static” spot meter which allows for up to twelve locations in the image to be recorded and recalled. These readings are updated automatically when a new prescan is performed, allowing rapid rechecking of important areas to see the effects of adjustments.
The live spot meter is available whenever the cursor is within the preview image area, regardless of the currently selected tool. The Spot Meter tool 
may be selected from the tool buttons at the top of the preview screen to mark static spot meter locations in the pre- view image.
RGB Data Values, EV Units
When the cursor is within the preview image area the information for the pixels under the cursor is displayed above the histogram. The information is continually updated as the cursor is moved to various locations within the image.
Above the histogram window, the individual red, green, and blue output data values are dis- played, with a range of zero (minimum brightness, or maximum print density) to 255 (maximum brightness, or minimum print density). The average of the red, green, and blue values is displayed as
the RGB value.
In addition to the RGB values, the relative EV display provides additional information about the pixels under the live spot meter cursor. The EV display is on the right side and is always preceded by a “+” or
Zero on this EV scale is preset to about 4.5 EV (4.5
Use the EV readout to determine the relative differences in luminance between various parts of the scene. This can be helpful in selecting or adjusting the tone curve and/or the lighting to achieve a predetermined range of image data.
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