Adobe 38039927 User Guide - Page 77

Adjusting tonal range

Page 77 highlights

ADOBE FIREWORKS CS3 72 User Guide Fireworks applies the Live Filter only to the new bitmap object, simulating the application of a filter to a pixel selection. Note: Although Live Filters are more flexible, large numbers of Live Filters in a document can slow down Fireworks performance. For more information, see "Controlling document redraw" on page 34. Adjusting tonal range You can use the Levels and Curves features to adjust a bitmap's tonal range. With Levels, you can correct bitmaps that contain a high concentration of pixels in the highlights, midtones, or shadows. Or you can use Auto Levels and let Fireworks adjust the tonal range for you. If you want more precise control over a bitmap's tonal range, you can use the Curves feature, which lets you adjust any color along the tonal range without affecting other colors. Evening out highlights, midtones, and shadows A bitmap with a full tonal range should have an even number of pixels in all areas. The Levels feature corrects bitmaps with a high concentration of pixels in the highlights, midtones, or shadows. Highlights corrects an excess of light pixels, which makes the image look washed out. Midtones corrects an excess of pixels in the midtones, which makes the image bland. Shadows corrects an excess of dark pixels, which hides much of the detail. The Levels feature sets the darkest pixels as black and the lightest pixels as white, then redistributes the midtones proportionally. This produces an image with the sharpest detail in all of its pixels. Original with pixels concentrated in the highlights; after adjusting with Levels You can use the Histogram in the Levels dialog box to view the pixel distribution of a bitmap. The Histogram is a graphical representation of the distribution of pixels in the highlights, midtones, and shadows. The Histogram helps you determine the best method of correcting an image's tonal range. A high concentration of pixels in the shadows or highlights indicates that you could improve the image by applying the Levels or Curves feature. The horizontal axis represents color values from darkest (0) to brightest (255). Read the horizontal axis from left to right: the darker pixels are on the left, the midtone pixels are in the center, and the brighter pixels are on the right. The vertical axis represents the number of pixels at each brightness level. Typically, you should adjust the highlights and shadows first. Adjusting the midtones second lets you improve their brightness value without affecting the highlights and shadows.

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ADOBE FIREWORKS CS3
User Guide
72
Fireworks applies the Live Filter only to the new bitmap object, simulating the application of a filter to a pixel
selection.
Note:
Although Live Filters are more flexible, large numbers of Live Filters in a document can slow down Fireworks
performance. For more information, see “Controlling document redraw” on page 34.
Adjusting tonal range
You can use the Levels and Curves features to adjust a bitmap’s tonal range. With Levels, you can correct bitmaps
that contain a high concentration of pixels in the highlights, midtones, or shadows. Or you can use Auto Levels and
let Fireworks adjust the tonal range for you. If you want more precise control over a bitmap’s tonal range, you can
use the Curves feature, which lets you adjust any color along the tonal range without affecting other colors.
Evening out highlights, midtones, and shadows
A bitmap with a full tonal range should have an even number of pixels in all areas. The Levels feature corrects
bitmaps with a high concentration of pixels in the highlights, midtones, or shadows.
Highlights
corrects an excess of light pixels, which makes the image look washed out.
Midtones
corrects an excess of pixels in the midtones, which makes the image bland.
Shadows
corrects an excess of dark pixels, which hides much of the detail.
The Levels feature sets the darkest pixels as black and the lightest pixels as white, then redistributes the midtones
proportionally. This produces an image with the sharpest detail in all of its pixels.
Original with pixels concentrated in the highlights; after adjusting with Levels
You can use the Histogram in the Levels dialog box to view the pixel distribution of a bitmap. The Histogram is a
graphical representation of the distribution of pixels in the highlights, midtones, and shadows.
The Histogram helps you determine the best method of correcting an image’s tonal range. A high concentration of
pixels in the shadows or highlights indicates that you could improve the image by applying the Levels or Curves
feature.
The horizontal axis represents color values from darkest (0) to brightest (255). Read the horizontal axis from left to
right: the darker pixels are on the left, the midtone pixels are in the center, and the brighter pixels are on the right.
The vertical axis represents the number of pixels at each brightness level. Typically, you should adjust the highlights
and shadows first. Adjusting the midtones second lets you improve their brightness value without affecting the
highlights and shadows.