Blue spot

Yet another photo of the 5/6 November night in Rovaniemi shows blue spot on the right. The diamond dust was often quite thick with no stars visible above, and in the lamp light it felt like being inside a crystal storm.

This is a single photo with some 30s exposure.

View below horizon

One of the advantages of bright spotlight is that you need not to go through the trouble of getting in Ilyushin IL-76 to have a good view of halos below horizon. In diamond dust, just place the light below the horizon and above the horizon you will have a below horizon halo view. As in the photo here.

Sun pillar threshold

Here is one stage of a display on the night of 5/6 November in Rovaniemi. The sharp intensity gradient at the zenith marks the outer edge of sun pillar, that has been formed from triangular columns - if parallel light simulations are to be believed.

Another display with crystals

Here is another display from the first diamond dust night Rovaniemi. The crystals were rather small as I was close to the snow guns. There was also Moilanen arc, but in the photo it is overexposed.

Parry arcs and possible 46° contact arc from Hungary

The weather in Vecsés, Hungary was mostly grey on 12 November, therefore the display came rather unexpected. Low in the horizon, covering the place of the parhelia and most of the 22° halo there was a thick cloud which remained there during the entire display. First the bright upper tangent arc appeared, but as the high clouds were moving, soon the upper sunvex Parry arc formed the second "V" in the sky ( 1 – 2 ). It was of the same intensity as the UTA, and I did not have to wait long until I could catch sight of the suncave Parry arc, as well ( 3 ). Unfortunately, Tape-arcs cannot be confirmed from the images.

When the Sun was of 4.1°-4.5° elevation, besides the supralateral arc, another halo patch formed under the CZA ( 4 – 5 ). I automatically took it as part of a 46° halo, but later it turned out that it might as well be 46° contact arc. As contact arcs are formed by Lowitz-oriented crystals, I had a closer look at the top of the 22° halo (what was outside the thick cloud), and unsharp masking of photos revealed lines that may be Lowitz arcs – if not jpg artefacts. It must be noted that all these images were taken about 5-7 minutes before the halo patch appeared. ( 6 - 7 ).

Beginning of diamond dust season

The diamond dust season began in Rovaniemi on the night of 1/2 November with three snow guns running in the ski jump. Here is one of the displays photographed that night. It is noteworthy that the crystals have cavities in their ends and yet the halos requiring basal faces are strong.

Long lasting column and plate halos with Lunar Wegener arc

After over a month of no halos I got bombarded by a serious halo series that started after I clocked out of work to go home, and before getting into the car I started firing away with my Nikon D-100. Through the duration the halos observed were 22° halo, upper and lower tangent arcs, fine upper suncave parry arc, bright parhelia with lowitz arcs, very long parhelic circle, 120° parhelia, a fine CZA, supralateral arc, and infralateral arcs ( 1 - 2 - 3 - 4 ). At sunset upper sunvex parry arc was observed and ended with a bright red tangent arc after the sun had set.


The show was not over yet because the Moon came up and there was 22° halo, upper tangent arc with parry arc, supralateral arc and CZA ( 5 ). Later on I looked away from the Moon to see bright and complete parhelic circle and very bright 120 degree parhelia ( 6 ). I also got to see blue spot very clearly ( 7 ). When the Moon got high enough for the circumscribed halo and Parry to merge I continued to shoot photos. Now here's the real shocker: the next day I looked at the batch of these lunar halo photos and I found a Wegener arc ( 8 )! I could not believe it. I also looked for heliac because the Parry arc got quite bright ( 9 ) but it was not to be found.