• Ultraviolet Photography
  •  

In the sky

Infrared
14 replies to this topic

#1 Øivind Tøien

    Member

  • Members+G
  • 195 posts
  • Location: Fairbanks, Alaska

Posted 27 December 2020 - 01:30

Posted Image

D40x IR- 720nm 105mm f/2.5 @ f/9 1/25s red channel swap
Øivind

#2 Cadmium

    Member

  • Members+G
  • 4,167 posts

Posted 27 December 2020 - 02:17

Øivind, Very interesting photo! :smile:

#3 Stefano

    Member

  • Members(+)
  • 1,796 posts
  • Location: Italy

Posted 27 December 2020 - 08:52

This photo can be hanged on a wall, in my opinion. It makes you think, it tickles you. Very nice.

#4 UlfW

    Ulf W

  • Members+G
  • 1,607 posts
  • Location: Sweden, Malmö

Posted 27 December 2020 - 09:24

A very strange cloud?
Like a kite suddenly disintegrating into black dust.
Ulf Wilhelmson
Curious and trying to see the invisible.

#5 Bernard Foot

    Bernard Foot

  • Members+G
  • 718 posts
  • Location: UK

Posted 27 December 2020 - 10:27

View PostUlfW, on 27 December 2020 - 09:24, said:

A very strange cloud?
Like a kite suddenly disintegrating into black dust.

I asumed it was an aircraft con-trail
Bernard Foot

#6 Øivind Tøien

    Member

  • Members+G
  • 195 posts
  • Location: Fairbanks, Alaska

Posted 27 December 2020 - 13:18

Thanks for the kind words all of you. Yes, on close inspection it appeared that there were 2 contrails at the source so aircraft con-trail confirmed. However at the time I got more associations to the Dementors of the Harry Potter movies, especially since the Jupiter-Saturn conjunction I tried to capture remained out of sight in spite of what looked like clear sky between darker clouds!
Øivind

#7 GaryR

    Member

  • Members+G
  • 312 posts
  • Location: London, Ontario, Canada

Posted 27 December 2020 - 16:04

I'm always intrigued by odd and interesting sky events, explained or otherwise.

#8 Øivind Tøien

    Member

  • Members+G
  • 195 posts
  • Location: Fairbanks, Alaska

Posted 27 December 2020 - 23:28

Thanks GaryR.
Here is visible spectrum reference/closer look from my D500 with 300mm f/4 PF:

Posted Image
Øivind

#9 GaryR

    Member

  • Members+G
  • 312 posts
  • Location: London, Ontario, Canada

Posted 28 December 2020 - 00:09

Even stranger up close!

#10 SteveE

    Member

  • Members
  • 126 posts
  • Location: United States

Posted 28 December 2020 - 01:03

You don't often see black contrails
- Steve

#11 Andy Perrin

    Member

  • Members+G
  • 4,084 posts
  • Location: United States

Posted 28 December 2020 - 01:44

It isn't really black, right? It's just that the light is coming from behind it.

#12 Øivind Tøien

    Member

  • Members+G
  • 195 posts
  • Location: Fairbanks, Alaska

Posted 28 December 2020 - 06:07

View PostAndy Perrin, on 28 December 2020 - 01:44, said:

It isn't really black, right? It's just that the light is coming from behind it.

That was my initial thought, but now I am not so sure about that. In the next frame captured 40 sec later the contrail seems to have been obscured (?) by a cloud layer that appears to be less dense than the contrail. I am not sure that would have happened if it was just backlight.
#1
Posted Image


Then about two minutes later it is continuous again, but more dissolved.
#2
Posted Image


A 100% crop of #1 of this post, the only one showing double tracks together with the one in the last post (but where is the backlighted aircraft?)

Posted Image

There might be something strange going on with the background clouds (noctilucent?) and winds at altitude.

In addition to traditional jets, Fairbanks has an Air Force base nearby (F35 and perhaps still some F16), and there are also plenty of turboprop and smaller private planes being used. Military crafts can be less clean, but also pretty easy to detect by the sound. No sound was heard from it.

Edited by Øivind Tøien, 28 December 2020 - 06:31.

Øivind

#13 colinbm

    Member

  • Members+G
  • 2,405 posts
  • Location: Australia

Posted 28 December 2020 - 06:15

Is it a flock of birds ?

#14 Andy Perrin

    Member

  • Members+G
  • 4,084 posts
  • Location: United States

Posted 28 December 2020 - 06:20

Nah, it's just backlit, the clouds are behind it. It's really hard to tell what's going on near sunset in 3D sometimes. I had this experience a few years ago, with a "meteor" that was actually a contrail lit by the sunset. The angle was different from your photo, so in mine the sun lit the contrail up instead:

Attached Image: contrail.jpg

Edited by Andy Perrin, 28 December 2020 - 06:21.


#15 Øivind Tøien

    Member

  • Members+G
  • 195 posts
  • Location: Fairbanks, Alaska

Posted 28 December 2020 - 06:40

You are probably right, but that discontinuity really caught my attention.
Øivind