Saturday, 21 February 2009

44 parhelia in Estonia

On 3rd of January it was possible in South-Estonia, Tartu to observe bright halo what was photographed by many people and was later reflected by media. Afterwards I was browsing the news ( 1 ) on and noticed that there might be 44° parhelion in picture taken by Aavo Omann ( 2 ). After closer inspection and browsing other captures it was clear that indeed it was 44° parhelion because there were no signs of 46° lateral arcs and the 22° upper tangent arc was weak.

Thursday, 5 February 2009

Halo display in Himos on the night of 2/3 February

On the evening and night of 2-3 February 2009, I was testing my new HID-spotlight that I finally got earlier on that same day. What would be better place for testing than nearby Himos ski resort in Jämsä, Finland. After being there for a few hours and seeing nothing but 22° halo with my lamp, I decided to go home. Luckily, at the same time, the sky started to clear and I first saw a half moon and Parry arc on that. Then I noticed also 46° halo and quickly took a few pictures and started heading back closer to Himos where I found a place to set up my camera and lamp. I stayed on that same location all the time, because there was some wind and things may change quickly.

Lamp elevation was about 2 or 3 degrees. Haloes were supralateral arc, parhelic circle, Wegener, subhelic, suncave Parry, Parry supralateral, 46°halo, Tricker, Greenler, "Ounasvaara arc" ( 1 ) (first observed by Marko Riikonen -07) and more. Temperature was between -7 to -10 C. See a few pictures and videos ( 2 ).

Sunday, 1 February 2009

Stacking a snow surface halo

Above is a comparison of snow surface halo stacked from 40 frames two different ways (click image for an animation). The photo on the right with crystal glitter is hand-stacked with Photoshop using Lighten-method, which was introduced by Piikki in the early winter ( 1 ). The other photo is stacked automatically with Registax. Because of the crystal glitter, Lighten-method provides more realistic output, though of course this is much enhanced realism.

Camera was moved between every shot some 30 cm sideways. 24° halo is well visible in 148 frame mirrored stack ( 2 ). Pyramidal crystals were observed with microscope, but unfortunately I could not get them photographed. The display was photographed on 30 January in Tampere, on Näsijärvi ice.