Sunday, 19 October 2014

Dodging and Burning

Here's a strange one.  I was out on St. Catherine's Hill again this afternoon, or rather, walking along the remnant ridge facing the hill, which is the western side of the deep cutting through Twyford Down that accommodates the M3 motorway.  The light was pretty, and there was a warm southern wind blowing: a nice day for a walk, and I was carrying a Fuji X100 to keep things light.

I always like this view, because of the interest that wiggly track down into the valley gives to an otherwise bland green vista:

However, in the process of adjusting the image this evening, I noticed something both odd and annoying.  Above the main clump of trees on the crown  of the hill there appeared to be a bright halo, very like the sort of artefact that would result, back in the darkroom days, from a bit of clumsy "dodging" i.e. selectively blocking some of the light from the enlarger with a card disc mounted on a wire, in order to brighten up a dark area.  Looking at it more closely, however, I could see that it appeared to be "real", in the sense that it wasn't just a bit of lens flare, or some other such optical artefact.  There really was a bright halo around the trees.

So, I crunched down the brightness, to bring it out, and this is what resulted:

Ignore the cyan coloration, which is an artefact, but look at the shape and texture of the halo.  Note that we are looking west, and the wind is coming from the south i.e. the left side of the picture, and it's around 15:30, so the sun is moderately low in the sky, off to the south-west.  I would say it's clearly some kind of brightly-illuminated turbulent flow, emanating from the trees, or from somewhere immediately behind, and blowing away to the north.  But what?

It's possible it's smoke from burning cleared undergrowth, which happens all over the hill, though that seems unlikely on a Sunday.  Also, immediately on the other side of the clump is the Mizmaze, which is a protected monument, and not a place where any responsible person would build a bonfire.  Of course, mentioning the Mizmaze opens the door to all sorts of bonkers speculation, but we won't go there.  Most likely, I think, is that it is simply the trees giving off water vapour after some heavy rainfall yesterday.  Curious, though, and not something I've ever noticed before.


Zouk Delors said...

There was a guest on this week's (or was it last week's?) Museum of Curiosity - - whose hobby was cloud-watching. He mentioned a rare effect where the sun is below the horizon but its light is reflected off clouds above the horizon. I wonder if this could be an example of that?

Unfortunately I can't remember what it's called, but anyone listening to the episode to find out will surely enjoy themselves anyway.

Mike C. said...

No, those would be "noctilucent" clouds, I expect.


Debra Morris said...

I nominate Alpenglow. You may well have imported it after your Austrian trip, Mike.

Mike C. said...


Hmm, maube, but I really don't see what my choice of breakfast cereal has to do with it.


Zouk Delors said...

I distinctly recall there WAS a breakfast cereal advertised as creating just such a glow. Don't think it was the alpine one, though. Reminiscent of the time (the 1920's?) when some food products had added radium, something their manufacturers were proud to boast of.

Mike C. said...


You're right! I'm thinking Ready Brek? Maybe there's a gang of Robin Hood types camped out up there living off the stuff, betrayed only by their mysterious glow...

There certainly used to be a Twyford Protest remnant camped out in broken down caravans around the bottom.


Zouk Delors said...

It's probably the sunlight reflecting off their crystals. Or a radium pile. I think you should go take a look next time you're up there.

Mike C. said...

I can feel an Enid Blyton adventure coming on... (it's that Ready Brek buzz...)


Adam Long said...

Intriguing. I've seen a yellow cloud of pollen being blown off a conifer plantation before, which was vaguely similar, though I was looking down on it from a hill.

Zouk Delors said...

The Adventures of the Weirdly Winsome One; Vol 1: One Goes Over The Hill.

"Barnabus Hat polished off his Ready Brek and, pausing only to quickly do the washing up and brush his tooth, reached for his favourite duffel coat with a tingle of anticipation.

After half a lifetime of repeatedly wandering the same small patch of ground, taking pictures of the odd bit of safety netting and so on for his diary -- and finding himself of late with more time on his hands -- Barnabus had decided that today was the day he would breach his habitual bounds and go ... over the hill.

"You be careful out there, Barney", said the wise old Professor, whose house he lodged at, "You know as well as I that there's a strange glow comes from over the hill, and nobody really knows what causes it".

[All characters entirely fictitious. Any resemblance to actual persons, living or dead, is coincidental]