PNG transparancy in IE6 with no scripts or hacks - Hmmm, i just stumbled over this screencast PNG-8 Alpha Transparency (screencast) :: Brenelz's Web Development Tips :: Winnipeg Web Development

Originally Posted by welshstew-webforums-dayz-jun-2008

There is a way to produce portable network graphics (png’s) so that they render correctly across all browsers without the need to employ complicated hacks and ie filter-based solutions or heavy javascript files, such as the twin helix approach or the supersleight.

Most times when a png is exported it is done so as a png32, which provides lossless compression and allows for more complex settings. All the goodies we love when designing a site.

However, within Fireworks you can also export png’s as a png8, which provides a palette based colour model (like gif’s) and which many believe only offers a 1 bit transparency option. However, if we play with some of the settings we are able to offer similar semi-transparency colors as a png32.

So if you use the export wizard and set it to export as png8 with indexed transparency, you will see the palette colours have been flattened and you are offered one, single transparent colour.

However, if you change these settings to alpha transparency, you will notice a few small “chunks” cut out of the some of the palette colours. These are the new semi-transparent colours.

The only downside is that complicated fade effects on images are not seen on IE5.5 & 6, but it still is a transparent image.

This works for IE5.5 and above (I haven’t tested lower than that), FF, Safari and Opera, so it’s a winner all round.

Also, the generated image files are smaller, which will increase delivery time, and , more importantly, there is no need to implement hacks, javascript files or any other third party coding, making the total delivery package smaller and therefore increasing the speed of your site.

Hope the above helps you all.