Algae optical effects (various years, Taivaanvahti)

[Timo Kuhmonen]

I collect here observation(s) for algae optics in Taivaanvahti for the summer season 2019.
******************
first one from Jari Luomanen
https://www.taivaanvahti.fi/observations/show/83091

[Elmar Schmidt]

Thanks, nice!

The off-center interferences must be Quetelet fringes, do they go by another name in Finnish?

Elmar

[Timo Kuhmonen]

In Taivaanvahti obswervation page -> if you press the info button, there is a description in finnish. See blue "i" letter inside a circle. I am not sure how the translation to these optics effects are done, but I understood those were known in foreing literature. I remember first hearing from algae optics, at observations from M. Riikonen...

[Elmar Schmidt]

Thanks again, Timo!

I clicked the (?) button and used Bing Translator (actually, not bad for Finnish...). Yes, the large radius rings through the sun's reflection are Quetelet rings. The other phenomena are coronae, and glories on the pond.

Kind regards

Elmar

[Claudia Hinz]

Nämä ovat ihania valokuvia!
Tervehdys Jarille ja kiitos osoituksesta.

[Alexander Haußmann]

Nice pictures! Never saw such phenomena myself though. It is remarkable that algae are the only other "partictles" apart from water drops that are known to cause glories.

Best regards,
Alex

[Timo Kuhmonen]

fyi. Observation by Satu J. (Lieksa, Finland). According to comments, 70...200 tele lens was used, this might be one point why the images do look like a bit different (to normal wide angle algae photos...)
https://www.taivaanvahti.fi/observations/show/83297

[Timo Kuhmonen]

observation from Kirkkonummi, Finland
https://www.taivaanvahti.fi/observations/show/85326

[Timo Kuhmonen]

fyi. Observation from Helsinki & Finland (21.6.2020)
https://www.taivaanvahti.fi/observations/show/91334

[Timo Kuhmonen]

FYI. Observation from Raisio & Finland (23.6.2020), this phenomena mentioned to be related to Nautococcus -algae. Colors on the phenomena seem to be very strong...
https://www.taivaanvahti.fi/observations/show/91349

[Timo Kuhmonen]

FYI; additional images from Raisio observation location (24.6.2020). To my opinion it looks very nice
https://www.taivaanvahti.fi/observations/show/91369