Yesterday I had a
wonderful idea: I was going to tell you about the problems that I had
in trying to take a photograph that Marcia wanted. It was when she
was writing Postcards from the Past.
You may remember the opening paragraph.
There are two moons
tonight. The round white shining disc, brittle and sharp-edged as
glass, stares down at its reflection lying on its back in the black
water of the lake. Nothing stirs. No whisper of wind ruffles the
surface. At the lake’s edge the wild cherry tree leans like an
elegant ghost, its delicate bare branches silver with ice, yearning
towards the past warmth of summer days. Tall stands of dogwood, their
bright wands of colour blotted into monochrome by the cold brilliant
light, guard the northern shore of the lake and cast spiked shadows
across the frosty grass.
We
were then at The Hermitage and it was watching the moon reflected
above the pond that gave Marcia this idea and she would have liked a
photograph of that scene to have beside her as she wrote. So I
blithely agreed to take one. Only it turned out to be impossible.
Yesterday I decided that I would show you the ‘failures’ as I
tried to meet her wishes but I can’t do that either: at some point
I deleted them as being of no great value.
Instead
I will use some ‘moony’ photographs that you might enjoy and try
to explain the problem in words.
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| This gives you some idea of the problem. Here the moon is exactly as Marcia wanted it to be but is so tiny - and this image doesn't even come down to ground level in the foreground. |
You
are standing to the north of the pond (in the Northern Hemisphere –
can those of you living on the other side of the equator please
adjust their thoughts accordingly). The moon has risen and is exactly
where I want it – due south – and is almost full. It could not be
more perfect so what was the problem. Well, when you look up at the
moon and glance down at the surface of the pond you see exactly what
Marcia described but it isn’t quite like that. What your brain does
is to reduce the distance between the moon and its reflection so that
it forms a pleasing whole in your brain.
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| Full moon but before it has risen very high in the sky and while it is retaining some of the colours of sunset. |
The
camera doesn't work like that. It shoots what is there with no distortions. The result is that the moon overhead looks tiny and the
reflection in the water doesn’t look like a mirror image of the
moon even though it is.
 |
| This is the last but one of a sequence in which I watched the cloud shaped like some strange animal seem to gobble up the moon. |
Then
there is another problem: getting the focus right. You look up at the
moon and your eyes focus on it and you retain that image as you look
down onto the surface of the water. Your eyes again focus, this time
on the reflection and that is all very satisfying.
 |
| This photograph says almost nothing but I rather like it. |
Not
so the camera. To focus on the moon you need to have the focus set at
infinity. To focus on the pond surface at something in the order of
twenty feet. You can’t have it both ways (although if it was a very
brightly lit scene you could (at least in theory) by stopping down
and so extending the depth of field. Even then you are pushing it:
the moon is 225,623 miles from the earth which works out at
1,191,289,440 feet or 59,569,472 times as far away as the pond
surface. It is probably possible with some sort of equipment but it
is definitely beyond the scope of anything I possess (so I plead
guilty to the charge of blaming my tools). The odd thing is that the
moon just looks horrid if it isn’t in focus – and the reflection
has to be crisp to make any sense.
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| Here the moon is in focus but the tree is not. |
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| This is the nearest I have to the image Marcia wanted. But here we are looking over a large stretch of water, the surface is not smooth so the reflection is disturbed, it was too early for the sky to be dark enough and the moon is far from full. Apart from that . . . |
