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woodylidstone.com Contents Introduction Understanding Alpha Creating an Alpha Channel Creating a Drop Shadow Filling the RGB Image Updating our Alpha Channel Finishing Up Review From the Desk New in Composer v10 / Symphony v3 Soft Shadows & Alpha in Photoshop Technical Articles Meridien Demystified

Alpha Channels & Soft Drop-Shadows << Previous: Understanding Alpha Channels Creating an Alpha Channel First we'll make an alpha channel. Then we'll adjust it to create a soft drop-shadow. The process in a nutshell is to open your image in Photoshop, make sure it's an RGB image, mask off the area you want to use as an alpha channel, and create the alpha channel using the mask. In an Alpha Channel, anything that's white is transparent to Media Composer while anything black is opaque (solid). "What about gray?", you ask? Gray is semitransparent. We'll use grays to make our drop-shadows semitransparent a bit later-on. Step 1: Open your image in Photoshop. Step 2: Make sure it's an RGB Image. Do this by selecting Image > Mode > RGB Color Images with an Indexed Color mode can't have alpha channels. Step 3: Mask the area you want to exclude. The areas you mask will become your alpha channel. (Tip: You can hold down shift while using the mask-wand to add that white area inside the "M") Step 4: Create the mask by switching to the Channels Palette, and click "Save Selection as Channel." This uses the mask to create a new channel, an Alpha Channel. View the alpha channel by clicking on the name of the newly created channel, "Alpha." When you view the alpha channel, Adobe Photoshop turns off the RGB channels. To view the RGB channels, click the channel name "RGB." This turns off viewing of the alpha channel and turns on viewing of the RGB channels, which show the actual, colored image. If you save the image now and import it into Media Composer, you'll see that Media Composer removes the portions of the image which are white in the alpha channel. (Be sure to tell Media Composer to detect the alpha channel by checking "Detect Alpha" in the Import's "Options" menu.) Next: Creating a Drop-Shadow >>