Odd radius column arc display

This display with 24°, 20° and 9° column arcs was observed at 10:47 on 29 June 2008 near Tselinograd by Konstantin Bespalov.
The original photos can be found here: ( 1 - 2 ), and a simulation of this display by Marko Riikonen here: ( 3 ).

Effects of crystal swarm density variation in halos

These photos and animation ( 1 ) show rather prominent effects in halos from crystal swarm density variation. Photos are from 7/8 December display in Rovaniemi.

Reflected Lowitz arcs with crystals

On the evening of 11 December diamond dust development near to skiresort in Sievi and in a spotlight beam a halo display was seen. Reflected Lowitz arcs ( 1 ) were rising from the parhelia, other halos were 22° halo, parhelic circle and 46° halo. I took some crystal samples which shows structure of crystals ( 2 ). On a later stage of the display one photo ( 3 ) looked quite weird, it seems there is a 18º halo present, but is it 18° halo or something else?

Another photo of 7/8 December in Rovaniemi

In this photo of 7/8 December in Rovaniemi there is nothing that we haven't seen before. But ordinary lamp halos are quite well developed, like the subanthelic arc that loops all the way to subanthelic point.

Merry Christmas to all.

Kern arc on 7/8 December in Rovaniemi

While sub-Kern was strong in the 7/8 December display, the Kern arc was less so. For one thing, I did not see it visually. In the two photos showing it, it can hardly be distinguished from the overlapping heliac arc. The other one of these photos is shown here. On the right is a heavily enhanced version zoomed at the zenith region.

Reflected Lowitz arcs in 7/8 December display

Two consecutive photos of the 7/8 December display contain reflected Lowitz arcs. The large image above is a stack of these two photos, the small upper image being heavily unsharp masked version of it. Reflected Lowitz arc is marked with an arrow in the small image.

The moment of reflected Lowitz arcs was short lasting: two photos showing them were taken within 35 seconds. Photos taken immediately before or after do not contain them. The lower small photo is timed one minute before their appearance, the halo composition being otherwise similar except for the reflected Lowitz arcs.

In these photos present is also upper sunvex Parry arc, which was missing from the display phase shown in my previous postings.

Lampside of 7/8 December

Here are photos taken towards the lamp. They were taken at the time when blue circle was strong on the opposite side of the sky. The upper ones are single images, exposure times 2 and 15 seconds. The lower images are stacked from a couple of frames with 1 to 2 seconds exposures.

Simulations say the lamp elevation is pretty close to 5 degrees. Images show upper sunvex Parry but no suncave Parry. Low lamp elevation may alone exclude suncave Parry, but as it is seen in some other photos, changes in crystal prism face ratios must be responsible for this difference. Best simulations of these photos are obtained with Parry crystals that are towards a triangular shape.