Use Photoshop to Make Transparent GIF Images

	STEP 1 Choose an image you want. Clear the margin of the image. You can use the Marquee Tool to do this. Drag the mouse pressing right button first to select a area you wish to be reserved, and then Choose Image/Crop. All space out of the selected area will be cut out.
	STEP 2 Fill the background of the image with the same color. CAUTION! The background color you choose MUST differ to any colors contained by reserved object because this color will be covered by background image in your WWW browser later. In this case, I choose pure white to be background.
	STEP 3 The maximum number of color of GIF is 256. If your image is of true color mode (i.e.. RGB, CMYK mode), you have to decrease the number of its color. Select Image / Mode / Indexed Color , and then an Indexed Color dialog box will open.
	If the original image has less then 256 colors, the system will set Palette to Exact mode. Otherwise please configure the dialog box following the left figure. The Adaptive of Palette option means that Photoshop will choose the best 256 colors to match the original image. The Diffusion of Dither option means the program will use diffusion dithering to present the color if it is not contained in the chosen 256 colors.
	STEP 4 Select File / Export / GIF89a Export... , and then a dialog box will be created to let you choose the background color.
	Take the dropper tool, move it over the position where you want it to be transparent, and then left-click your mouse. You will find all the areas which has the same color will become light gray. This means these areas will be transparent when they are shown in the web browser. There is an advantage of Photoshop. You are able to choose more than one color to be transparent. Just click on other color, more ones will become transparent.
	Bush OK button, and the left figure is the result when you view it in browser.

Copyright by Jack Hung, 1995-1997. All Rights Reserved.
Last update: 29/3/1997