Preserving multilevel transparency in PNG-24 images

When you create a PNG-24 image, you can preserve variable transparency, such as that in an anti-aliased image on a transparent layer, using a feature called alpha transparency. Alpha transparency preserves up to 256 levels of transparency in a PNG image. When the PNG is displayed in a browser using a plug-in that supports alpha transparency, the PNG displays multilevel transparency, and the image's edges will blend with any Web background.

To create variable transparency in a PNG-24 image:

1 Import a Smart Photoshop image that contains transparency or select a Smart Photoshop object already on a Web page and click Settings in the Smart Image Inspector.

2 In the Optimize panel in the Save For Web dialog box, select PNG-24 from the format menu.

3 Select Transparency.

4 Select None from the Matte menu.

Images and Page Design > Making transparent and matted Photoshop images > Preserving multilevel transparency in PNG-24 images