Thanks for the reply. I wasn't using QtQuick so I couldn't use that as you suggested but I tried using the C++ equivalent and it acted the same as the property animation. After all the QPropertyAnimation pretty much just works on the QGraphicsOpacityEffect directly which is probably exactly what QtQuick uses under the hood to do it's opacity.
Sorry for the delay in response I didn't realize the new forum system didn't email me when I got a response to a thread and I was busy enough with work not to check it. :)
Also, I figured out what was causing it. It seems that I was using a QLabel with setAutoFillBackground(true) and the opacity effect couldn't handle that for some reason. When I removed that (I'll find another way to draw the background) it fades out properly. Just in case anyone else gets here from google.
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