Another stacked Sony a7r image from a while ago tracked with the Polarie.
7 x 30 seconds ISO6400 F4 Zeiss FE55 F1.8 lens.
Processing in Adobe LR CC, PixInsight and Photoshop CC.
There seems to be some red airglow as well as a bit of green airglow in the image so that band at the lower 1/3rd is not an artefact.
http://www.pbase.com/image/161740851/large regular size
http://www.pbase.com/image/161740851/original larger size
Greg.