I'm working with QGIS 2.8.1. I have a project with CRS: 3947 (Central-Western France) and several layers in the same CRS. I have not activated the 'On the fly' CRS transformation.
I add the Bing Aerial layer through OpenLayers plugin. My project then automatically goes in CRS 3857 (OTF), despite the settings explained before... This is not a big issue because my vector layers display automatically follows the Bing Aerial and align perfectly.
I then create a new composer with a map window. The vector layers are perfectly aligned on the Bing Aerial background. The issue comes when I export the composer as a PDF or PNG, resulting in a big misalignment between vector layers and Bing Aerial... I don't understand why the printing process modifies what is displayed in the composer.
Any idea about this issue and how I could solve it?