Reply To: Opacity affecting layers below

CreeoDo-

The shift you're seeing is most likely what happens when you have RGB colors on the spread and you're using CMYK Transparency Blend Space. You can check in in the Edit menu. When you introduce transparency onto a spread, everything on the spread gets converted on the fly to the blend space so that colors can be blended. It's just a side effect of InDesign allowing you to mix CMYK and RGB colors on the same spread: they have to be converted to a common color space to blend. So your intuition was exactly right. And it's not a bug, it's a feature :)

Jennifer-

Not sure if this is what's happening in your case.