2009. augusztus 16., vasárnap

20° column arc


This minor odd radius came with a surprise after stacking. Outside the 18° halo / plate arc there seems to be a faint, but rather well defined 20° column arc. As there is no sign of 9° stuff, crystals had no middle prism which is rather rare situation. The display was observed on August 9 in Kontiolahti.

8 megjegyzés:

  1. Hey Marko,

    I did the tif conversion and did a stack of the display that had 9,20,22,24,and 35d rings well theres also 18d ring as well and the 35d ring is long and colorful. Problem is though when I USM with photoshop and try to save copy as JPG it wont let me do that.

    VálaszTörlés
  2. Michael,

    You need to flatten the image and transform it into an 8 bit image. I suppose this is the problem. JPG does not support 16 bit image data.

    I the bit depth or the flatting is not the answer, then you need to give us a little more details of your process.

    VálaszTörlés
  3. Nice one ! Here the August has been lack of halos. But on 15th I got my first upper sunvex Parry arc. The brightness was uniform with the tangent arc.

    VálaszTörlés
  4. Shoot Marko I got simultaneous concave and convex parry arc one a couple years ago.

    VálaszTörlés
  5. Congrats on first sunvex Parry Krusel. Not an easy catch in high clouds. Even upper suncave is quite rare with naked eye.

    VálaszTörlés
  6. That is pretty accurate simulation I must say ! How many frames ? What halo forms were visible with naked eye except the 20 column arc ?

    VálaszTörlés
  7. When Marko first saw it there was 18 and 23 degree rings with upper 23d plate arc.

    VálaszTörlés
  8. That's just 25 frames. The display faded away. With naked eye I saw 23 and 18 arcs.

    VálaszTörlés