The moon halo display vanished as it got eventually overcast. It was
still low stratus with occasional fog on the ground, but apparently
the moisture just became too much for the snow guns' ice dust to
nucleate a hole. Diamond dust nevertheless continued under cloudy skies
and I turned on the spotlight. It was rather good, plate crystals
still in charge and with negative elevation lamp (about 11° below
horizon) there appeared several "super"-halos (equal to "sub"-halos when
light is above the horizon). All were visible to the naked eye, the
superparhelic circle at the superanthelic region was bright. At its
best the superparhelic circle extended all the way to the
superparhelia but I did not get that stage photographed. At the same
time was also normal parhelic circle visible. I though of seeing a
ghost of super-120° parhelion, but decided it was just white snow on
the far hill. In the photos, however, super-120° parhelia are visible
in a similar ghostly manner, so probably that was what I saw.
Getting these photos was mostly waiting. Mainly it was water fog, but then, for maximum few minutes at a time good crystal swarms swept by. In one exposure both water fog and diamond dust stage was captured so that there is also fogbow visible. In reality halos and fogbow were not much visible at the same time. Water fog and diamond dust don't just occur simultaneously. Eventually it got worse and I headed back to Joensuu. But on the way there was diamond dust at the quarry, 7 km as the crow flies from Mustavaara. So I took some photos there as well, climbing up a gravel mountain, leaving the lamp at the bottom and thus obtaining about 35° negative light source elevation.
Getting these photos was mostly waiting. Mainly it was water fog, but then, for maximum few minutes at a time good crystal swarms swept by. In one exposure both water fog and diamond dust stage was captured so that there is also fogbow visible. In reality halos and fogbow were not much visible at the same time. Water fog and diamond dust don't just occur simultaneously. Eventually it got worse and I headed back to Joensuu. But on the way there was diamond dust at the quarry, 7 km as the crow flies from Mustavaara. So I took some photos there as well, climbing up a gravel mountain, leaving the lamp at the bottom and thus obtaining about 35° negative light source elevation.
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