The image of Christ, the Sign of the Theotokos, in the apse with 3 tall narrow windows, the one with ho ôn in the halo, is that an image from 1164 or from the restoration of 1555? I'm trying to date the earliest appearances of ho ôn in Christ's halo. I suspect that since ther is no ho ôn in any of the images from 1164, the image that shows ho ôn is from a later date. Can anyone confirm this information? Thanks a lot.