[modelboatmayhem (OP)]

Phantom Plane shadow?

Took this photo this week in Ferry Meadows, Peterborough...



 [ Invalid Attachment ]


 What's going on? At first I thought there was a 2nd plane but realised it was some sort of shadow / reflection from the higher plane creating the vapour trail.

1. Why is the "shadow" larger and brighter than the real plane?
2. Why does the vapour trail not cause a shadow?

Perplexed of Peterborough - newbielink:http://www.picturesofpeterborough.co.uk [nonactive]

[neilep]

Hey Martin,

Hope you don't mind but I thought your photo question required it's own topic.

I also fixed it so that your photo is in full view !

welcome to the site

neil

[RD]

Ghost image (optics)

A feature or shape at the focal plane of a camera or other optical instrument that is not present in an actual scene, or an unfocused duplicate image that is overlaid upon a desired image. Ghost images, or ghosts, are caused by reflections from the surfaces of lenses or windows. Each glass surface divides incoming light into two parts: a refracted part that passes through the surface, and a reflected part that is turned back. If the reflected light is turned back again by reflection from another glass surface or a mirror, it may travel to the focal plane to form a ghost image. Ghost images may appear as an out-of-focus blur or smudge, a sharp circle or polygon with the shape of the camera iris or other aperture, or a false image of an object within a scene.

http://www.accessscience.com

[neilep]

Ghost image (optics)

A feature or shape at the focal plane of a camera or other optical instrument that is not present in an actual scene, or an unfocused duplicate image that is overlaid upon a desired image. Ghost images, or ghosts, are caused by reflections from the surfaces of lenses or windows. Each glass surface divides incoming light into two parts: a refracted part that passes through the surface, and a reflected part that is turned back. If the reflected light is turned back again by reflection from another glass surface or a mirror, it may travel to the focal plane to form a ghost image. Ghost images may appear as an out-of-focus blur or smudge, a sharp circle or polygon with the shape of the camera iris or other aperture, or a false image of an object within a scene.

http://www.accessscience.com

Why is the vapour trail NOT replictaed ?

[RD]

Why is the vapour trail NOT replictaed ?

Two possibilities come to mind ...
#1. the metallic reflection from the body of the plane may have been much brighter than the vapour trails: i.e. the vapour trails were not bright enough to form a ghost image.

#2. If a polarising filter was used on the camera lens it could permit the light from the metallic reflection from the plane, but severely attenuate the light from the rest of the scene, (see point #1) 

A polarizing filter, used both in color and black and white photography, filters out light polarized perpendicularly to the axis of the filter. This has two applications in photography: it reduces reflections from non-metallic surfaces, and can darken the sky.

http://en.wikipedia.org/wiki/Photographic_filter#Polarizer

[BTW I tried superimposing the plane images to see if it was two real planes. The images match perfectly: 1 plane & 1 ghost image]

[modelboatmayhem (OP)]

Well that's all very interesting apart from the fact that a dozen of us all saw
it with the naked eye and I was just lucky with the camera, just pointing it in
the general direction and shooting away... I was really surprised to see I had
captured it when I got home.

[RD]

I've found something similar ...
 [ Invalid Attachment ]
http://www.pbase.com/john_cooper/image/53695537

Again the ghost image plane does not have trails.

[AllenG]

It could be two planes flying in the same direction but at different altitudes where atmospheric conditions are conducive to the forming of contrails at one altitude and not the other.

[RD]

In both the cases above the images of the planes can be superimposed: they are the same size and have the same orientation.
 This seems an unlikely (and dangerous) coincidence for two real planes.

[glovesforfoxes]

did you talk about how there was a 2nd plane in the sky while actually taking pictures of it?

[RD]

Google earth has ghost planes ... http://www.ntnews.com.au/article/2009/01/30/30231_ntnews.html

 [ Invalid Attachment ]
http://www.moillusions.com/2007/01/ghost-airplane-illusion.html

These are after-images in sequential frames caused by the very bright reflection from the mirror-like body of the plane.
 [like when you can still see the image of the flash a minute after you've had your picture taken].

[BTW after-images could not occur with a film camera].

[LeeE]

I think that both of the pictures show two aircraft.  They only need to keep a vertical separation of 1000ft.  They could also be military freight aircraft flying in formation - this is actually quite common atm, with a lot of supplies currently being flown to Afghanistan and Iraq.