Nikon 4 user manual Viewing the Histogram, Histogram button, Channel Selection Shortcuts

Image Adjustment

Viewing the Histogram

The first step in adjusting tone levels and color balance in the Curves palette is to view the histogram displayed in the background of the curve edit display. The histogram tells you what tones are present in the original image and in what amounts, information that you will use when setting the black point and white point and editing curves. The histogram takes the form of a bar graph. The horizontal axis gives the tone level, with shadows to the left and highlights to the right. The vertical axis gives the number of pixels of each tone level found in the image, scaled to fit in the curve edit display.

Histogram button

By assigning the darkest tones in the image an output value of zero and the brightest tones in the image an output value of 255, blacks will be output as blacks and whites as whites, making the most effective use of the dynamic range of the output device.

To view the distribution of tones in the final, output image after changes to curves, click and hold the Histogram button .

Channel Selection

You can modify tones for all colors in the image using the master curve, or select any of the red, green, and blue curves for edit- ing using the channel menu. The histogram shows tone levels for the selected channel only. When the master curve is selected, the

auto-contrast button and white-point and black-point eyedropper tools apply simultaneously to all of the red, green, and blue curves (the master curve is unaffected). When one of the red, green, and blue curves is selected, these controls can be used to edit the selected curve only.

The Histogram (RAW/16-Bit TIFF Images Only)

To reduce display times when dealing with large amounts of image data, Nikon Capture 4 may display a histogram containing vertical lines.

Channel Selection Shortcuts
The current channel can also be selected using the following shortcuts:
• Ctrl ~ (Windows)/	~ (Macintosh)	• Ctrl 1 (Windows)/	1 (Macintosh)
Master channel (RGB)		Red channel
• Ctrl 2 (Windows)/	2 (Macintosh)	• Ctrl 3 (Windows)/	3 (Macintosh)
Green channel		Blue channel

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