Hi all, What a night that was. It's been a long time since there has been a major NLC visible before midnight(ut) in this part of the world. It was quite spectacular and even when the sun was at it's lowest depression below the horizon it was still a sizable display.
After midnight it grew in scale and complexity. Amongst the complex patterns there were distinctive bands indicative of atmospheric "gravity waves" (These should really be called neutral bouyancy waves, though, to avoid confusion with the now discovered celestial namesake!)
I think it's always nice to see the NLC close to the solstice, the bright twilight and the ilumination of the NLC have a very special light. What I noticed with this display is that a lot of the features were "soft" and the light was quite blue. Given the physics It suggest to me that the cloud particle size was particulalry small in this formation. Be interesting to compare to other displays this year...
Hi, Indeed!, I'm still working through all the shots I took. An interesting colour effect. It definitely looked "bluer" than usual and the pictures had a very distinctive look to them. I'm glad to see your's look so similar. As with the post on colour balance it's s tricky situation given all the factors in play. There were several faint signatures of "gravity waves" throughout the displays. One is shown in the pic. Had to overexpose the lower bit to bring it out. Even through all the NLC formation complexity these are interesting to follow. cheers, Bill.
you wrote 'Amongst the complex patterns there were distinctive bands indicative of atmospheric "gravity waves" (These should really be called neutral bouyancy waves, though, to avoid confusion with the now discovered celestial namesake!' The cosmic waves discovered by LIGO are Gravitational Waves. The atmospheric phenomena are known as you stated as Gravity Waves'. While the two are similar enough to cause confusion to some I beleive it is quite clear to those with experiance which is which
What white balance were you using for your images above ? If it was automatic white balance can you determine what temperature the camera decided to use from the EXIF data and post it to the thread I created about what white balance shouild be used for NLC.
If you have trouble finding the colour temperature can you pm me a copy of the images as they were downloaded from the camera and I will try to decode what white balance / colour temperature was used. As I posted in the other thread the 'Color Temperature' field on Canon cameras seems to show what the menu setting was not the actual measured temperature.