The display occurred on 18 of March and I observed it from Vilnius, Lithuania.
For the whole day, cirrostratus clouds covered the entire sky. The clouds were moving eastward and also sublimating.
I started observing at 10:25 EET. At that time there were already odd radius halos present: with the naked eye, you could definitely notice both the 9° and 18° halos.
At 11:45, only the 9° halo was present, and at 12:00 the odd radius halos disappeared. After that, and until around 17:00, there were a faint 22° halo and tangent arc visible.
I photographed the halos in raw format with a DSLR camera. After enhancing the images, a 35° halo became visible, but I was surprised the most to see a ring between 9° and 18° halos, which appeared to be a 13° halo. After sending the images to The Halo Vault, I got a confirmation about this from Nicolas Lefaudeux and the Halo Vault team.
Here are some pictures from the display, last two of them in the sequence were processed by Nicolas Lefaudeux:
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| (All images copyright Donatas Gražulis) |
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| (Image processed by Nicolas Lefaudeux) |
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| (Image processed by Nicolas Lefaudeux) |
A similar feature appears in an older photograph that I took on 25 of June 2019. This is the only photo from that day that this appears in; it was taken with a phone:
- Donatas Gražulis
13° halo tends to keep out of sight until a set of images is stacked. Is this the first single image 13° halo in high clouds? (Gražulis presents also a case from 2019, but to my eye it is borderline).
ReplyDeleteMarko Riikonen
This comment has been removed by the author.
ReplyDeleteHello there, this is an interesting display.
ReplyDeleteI got similar ones in the past years, and indeed, unless you stack the images, rendered in with Blue minus Red, it's impossible to discriminate it:
https://www.flickr.com/photos/gaukouphoto/43994611714/
https://www.flickr.com/photos/gaukouphoto/44088228171
https://www.flickr.com/photos/gaukouphoto/47632649851/
https://www.flickr.com/photos/gaukouphoto/43994611714/
https://www.flickr.com/photos/gaukouphoto/52359675670
I kept some of the raw images from those 5 displays, but haven't seriously tried to see if there is a 13° halo reachable in them.
Hi Nicolas, this is a superb set of 13 halos taken over a relatively short space of time. While they don't take anything away from Donatas' achievement of capturing a single frame 13, they do present an overwhelmingly powerful argument for stacking as a matter of course. Bravo!
ReplyDeleteHello there again,
ReplyDeletewhen you look for it, you have more chance to find it. And there it is.
I finally found in some of my Raw images occurrences of 13° halos, with B&W rendering too.
You'll find in the following link:
- 2 raws images where the 13° halo is seeable.
- a stack, made from 7x4 successive images
- a time-lapse from the complete stack, in B&W rendering
https://tinyurl.com/369xzdav
As I don't have, as of this day, completed my processing, I still have all the raw images if someone is interested ;-)
Like in the one above from Donatas, the reddish (then grey-black in B-R images) part of it is pretty thick, like in the 9° and 18° halos as well.
In all my 13° displays, for now, 13° reddish part is thick too.
Regards.
Nicolas Rossetto
I have come to realize my photo working skills are way behind the curve. I hardly even could get the 13° halo from Gražulis' raws out and then Lefadeux shows a processing that makes it on par of the best stacked cases. So, that I quite didn't get the 13° halo out from the two Rosetto's single photos is not to be put any weight on. If it is something that indeed convinces if we had only that one photo of the display, then it qualifes as a single image catch.
ReplyDeleteMarko Riikonen
Hi,
ReplyDeleteI am sharing all unprocessed pictures from the 18th of march display here:
https://drive.google.com/drive/folders/1fOHcr0uTCe-QbcBGaUHWLnByGqvuhElM?usp=sharing
- Donatas
Hello Donatas.
ReplyDeleteThank you for the sharing. Indeed, the 13° halo is pretty clear on those images, with a B-R rendering.
To Marko:
Here is the base settings I use with UFRaw plugin (standalone) for Gimp to process image in b&w with basic B-R rendering, so you can have a example to retry to see the 13° ring with the raw you have access to. (3 tabs edited, other tabs are with default values)
https://live.staticflickr.com/65535/52840077488_f39ee821c4_o.png