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Macromedia Fireworks MX Tutorials

Bitmaps in FW MX / Adjusting Bitmap Color and Tone

Subtitles of the Movie

Fireworks has color and tone adjustment filters to help you to improve and enhance the colors in your bitmap images. You can adjust the contrast and brightness, the tonal range, and the hue and color saturation of your images. You can also easily add your favorite Photoshop plug-ins to Fireworks, and apply them to bitmaps using the filters menu or the live effects area of the properties inspector. Applying filters as live affects from the property inspector is non-destructive. Live effects do not permanently alter the pixels. You can remove or edit them at any time. If you apply a filter to a selected vector object using the filters menu, the selection is converted to a bitmap image. You can use the levels and curves feature to adjust a bitmap's tonal range. With levels, you can correct bitmaps that contain a high concentration of pixels in the highlights, mid tones or shadows. Or you can just use auto-levels and let Fireworks adjust the tonal range for you. However, if you want more precise control over a bitmap's tonal range, you can use curves, which enables you to adjust any color along a tonal range without affecting other colors. Let's take a look at levels under the filters menu. I am going to drag the dialogue box up here. And by dragging and selecting these various pointers, we can adjust the output level of the pixels over a broader range. 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, mid-tones or shadows. And you can see that our bitmap image looks considerably better. I am going to go ahead and cancel this. I am going to select filters again. But this time I am going to select auto-levels and let Fireworks make the changes for us. And fact, it actually did a pretty decent job. And one thing to keep in mind, which if you are a Designer you are already aware of: anytime you bring in a digital photograph or a scanned image, you really need to correct the levels, as well as apply a little bit un-sharpen mask to bring up the image just a little bit more. And in fact, this shot of mailbox was used on the web as part of a promotion, and this was short with a digital camera. And the various steps that I am applying here were used optimize the image before we used it on the web. And with the auto levels filter applied, I am going to jump back under filters>adjust color and take a look at levels again. And you can see in the histogram that the levels have been evenly distributed. The histogram is a graphical illustration of the distribution of pixels in the highlights, mid-tones and shadows of the bitmap. 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 you could improve the image by applying the levels or curves feature. The horizontal axis illustrates the color values from darkest which is zero, to brightest which is 255. Read the horizontal axis from left to right. The left depicts the darker pixels and the center depicts the mid-tone pixels and the right depicts the brighter pixels. The vertical axis depicts the number of pixels at each brightness level. Typically you should adjust the highlights and shadows first. Adjusting the mid-tones second lets you improve their brightness value without affecting the highlights and shadows. I am going to go ahead and cancel this operation, and select undo, and go back to filters and this time select curves. Curves is similar to levels, but it provides a more precise control over the tonal range. Whereas levels use highlights, shadows and mid-tones to correct the tonal range, curves lets you adjust any color along the tonal range instead of only three variables without affecting other colors. For example, you can use curves to correct for a color cast caused by a particular lighting condition. The grid in the curves dialogue box illustrates two brightness values. The horizontal axis depicts the original brightness of the pixels shown in the input box. The vertical axis represents the new brightness values shown in the output box. So when you first open up the curves dialogue box, the diagonal line indicates that there are no changes that have been made. So the input and output values are the same for all pixels. Simply selecting an area on the curve and adjusting it, you can see the input and output values are changed. In addition, you can see the results on the image. You can also adjust the highlights, shadows and mid-tones using the shadow, highlight or mid-tone eyedropper in the levels or curves dialogue box. Before I adjust this, I am going to bring our curves back a diagonal line. And the first thing you need to do is select a channel. I will go ahead and select the red channel, and select a dark area on the screen. Click on the mid-tone, select a mid-tone, and then select a highlight. And I can do this for each channel. I will go ahead and jump back into RGB, and I will go ahead cancel this operation. But before I do so, I am going to go ahead and select auto. And you can see the curves have been adjusted automatically for us. I will go and cancel this operation. The next thing I want to look at is brightness and contrast. And this dialogue box is very straightforward. As we adjust the brightness and contrast, we can see the corresponding effect on the canvas. Essentially the brightness/contrast feature modifies the contrast or brightness of pixels with n this image. This affects the highlights, the shadows, and the mid-tones of the image. You typically use brightness/contrast when correcting images that are too dark or too light. We can also adjust the hue and saturation. You use the hue saturation feature to adjust the shade of a color (its hue), and the intensity of the color - its saturation or the lightness of a color in a range. I will go ahead and scroll the hue to the right a little bit. And you can see that our flag has been dramatically changed. And this because this is really the only object in this photograph that has a color associated with it. The rest is been desaturated, or more black and white. We can also change a saturation level from high to low. And the lower we go the more we make the image black and white. And we can also adjust the lightness - making it lighter and darker for our image. I will go head and cancel this operation. And I am going ahead and apply auto-levels here for this last filter I want to show, and that is invert. And invert does exactly that; first you need to select the bitmap image what to change. and then go to filters>auto-color, and then invert. And this will completely invert the selection - both black and white, and with colors. ant to show, and that is invert. And invert does exactly that; first you need to select the bitmap image what to change. and then go to filters>auto-color, and then invert. And this will completely invert the selection - both black and white, and with colors.

Tutorial Information

Course: Macromedia Fireworks MX
Author: Scott Doucet
SKU: 33407
ISBN: 1932072179
Release Date: 2003-01-08
Duration: 6 hrs / 81 lessons
Captions: For Online University members only
Compatibility: Vista/XP/2000, OS X, Linux
QuickTime 7, Flash 8

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