[RedTyger]

PNG 24s can do opacity, unless my copy of Photoshop is mislabelled.

Originally Posted by davidw

I've not worked (much) with 32-bit PNGs, but I have worked mostly with PNG-24 and have seen the light-blue effect with that in IE as opposed to the non-transparancy. There are fixes out there that I've seen, but the ones I've implemented to ensure IE 6 and 7 render the format properly have caused a slight delay in processing the image and therefore showing the light-blue "haze" or "transparency overlay" for a part of a second - enough to be an annoyance if you work with them enough.

My .02 cents for working with PNGs.

There is a CSS-only solution which works well, particularly where the PNGs are used for layout purposes. It has no negative side effects, but does have the caveat of not always being suitable because it transfers the PNG to being an element's background image. Works back to IE5 or IE5.5, something like that. I'll post it if you need it.

Originally Posted by Michael Morris

Which is why I advocate using PNG8. IE 5.5, 6 and 7 display this form of PNG without a problem.

Actually they do, IE sometimes renders the palette off by a shade or so, depending on your image. If you're trying to precisely match a shade then it can show up with the colours not matching.

Run through a few of the tests on this page in Firefox and a version of IE. If you only see a one-colour box, the browser is rendering correctly, or you can see the effect here. That screenshot is from the beta, I don't if it was fixed in the gold release. I'd appreciate knowing actually!