September 6, 2006: Oil spill in Philippines

[tulzscha]

Originally Posted by xoxoxoBruce

Tulzscha, the photographer in your link was on a pressurized commercial airliner at considerable altitude.

Yeah, and the dude/dudette/automaton who took *this* picture was on a pressurized airliner at a lower altitude. And pressure has nothing to do with it - Plexiglas does. *shrug*

Dunno why my first thought is "plexiglas rainbow", but it is.

Plus, are those blurry fingers along the right side of the photo?

[xoxoxoBruce]

How do you know it was a pressurized airliner and not a private or military plane?
Pressure has everything to do with it, the pressure differential between the inside and outside causes strain in the widow and produces the color patterns. Ever see that effect through a plane window on the ground? I don't think so, unless the window has been permanently distorted by a twist in the airframe.

People take pictures through Plexiglas all the time. I take them through my storm doors frequently, without color patterns.

[tulzscha]

Of course, my argument hinges on the somewhat dubious notion that someone had a polarizer on their snapshot camera, so, well, hmm...

[RodinPat]

Quick experiment:
Drive a car with tinted windows down to the beach.
Put on a pair of polaroid sunglasses.
Watch the rainbows sparkle on the sea.
Try it in your own time, no pressure.

I think it must be some form of refraction of the reflected sunlight through the two different films.

Do you think that our photographer used a polaroid lense?

[xoxoxoBruce]

Another Aussie! Welcome to the Cellar, RodinPat.
We're getting a formidable contingent from down under....that's great.

tulzscha, you may be right. The IOtD picture could be picking up some color from the window combined with the photographic technique. I was just pointing out the other oil slicks we've seen in the news, and in person, show color, so it can't be the total cause.

The effect shown in the website you linked is an extreme case and exactly what we do in the lab to show strain. Attaching Plexiglas to a part and subjecting the part to stress, the strain will show up in the Plexiglas clearly enough to photograph it.

[tulzscha]

Originally Posted by xoxoxoBruce

tulzscha, you may be right. The IOtD picture could be picking up some color from the window combined with the photographic technique. I was just pointing out the other oil slicks we've seen in the news, and in person, show color, so it can't be the total cause.

Looking at the Yahoo gallery yields the following slick pix:

http://news.yahoo.com/photos/ss/even...l/&curPhoto=21
http://news.yahoo.com/photos/ss/even...l/&curPhoto=24

21 is a similar up-sun shot, at sort of a similar angle (?), and it shows only the pancake and sheen, without the overall rainbows. But, then, aerial observation of oil spills is, um, kind of tricky?

"Because lighting conditions are highly variable during an actual spill, oil thickness observations based on the color of the slick are generally not reliable. Glare due to very low sun angles and sunlight directly overhead can make observations particularly difficult due to poor contrast between the oil sheen and water. Additionally, observations of the oil slick can be hampered by viewing in an up-sun direction, wearing sun glasses or face shields, or looking through Plexiglas windows."
http://response.restoration.noaa.gov...2_OilatSea.pdf

Dunno. It's a neat picture at any rate... Which I guess is, um, the point of the thing. =]

[xoxoxoBruce]

And......

Oil that is known to be close to the coastline is best viewed from a helicopter. Ideally, a door or window is removed so that the main observer can view the oil looking straight down, without the finer details of the oil slick being obscured by Plexiglas.

[tulzscha]

We just need Filipino Cellarites to do some on-the-spot testing and reportage!

Or, alternatively, I *do* need a vacation....