This display occurred on 22th February 2017 in Izborsk (Pskov region, Russia). In the morning it was sunny and the first cirrus started to arrive around 13-00. In that moment, I saw a faint 22° halo, but it was visible because the cloud layer was smooth. Also it seemed to me that I saw a 9° halo through the viewfinder of my camera. The stacks showed pyramidal halos such as 9°, 24° and 35° halo.
The 24° halo looks pretty curious, because B-R processing shows the pause in 24° ring in area of upper tangent arc. It reminds me of 24° column arcs from crystals with big tilts. 9° halo also looks curious, brighter on the sides than on the top, what looks like 9° column arcs.
What do you think of that?