9.5 Point of View

I have cameras to load with film, attach to tripods and then find compositionally interesting locations to place them. The winds are dying, and the lake is approaching that mirror finish that will show stars beneath the depths of its reflecting surface. The conditions are right, but there is yet one more requirement: I need to be able to find a patch of dry land to plant the feet of a tripod that still allows me to compose a view that contains the sky, the horizon, and enough of the reflecting lake to capture the spirit of this place, the recollection of a distant experience. I find that in spite of my wide-angle lenses and film formats, I cannot get enough of the scene in the viewfinder to satisfy me. I make some guesses about how the stars will move over the next few hours and arrange the cameras at the edge of the lake.

There is an interesting tradeoff in making this exacting picture. The height of the camera above the lake’s surface is very important. Imagine if it were at the actual level of the water. The view of the mirror would be very oblique. This is good for the reflected light from a faint star in reaching the film- a glancing reflection from any polished surface is nearly 100 percent, but the perspective would foreshorten the lake to nearly nothing, and if there was any view at all, it would be a reflection of the sky at the horizon, usually a murky soup of air and distant lights.

To get a larger view of the reflection, the camera must be above the lake’s surface. As one increases the height, the area of reflected sky increases, showing the stars that are higher and higher above the horizon. But as the angle increases, the reflected energy decreases, until a point where only the brightest stars can make any impression on the film that is recording it. There is perhaps an optimal camera height for obtaining a pleasing composition that contains startrail reflections. I do not know what it is, but I will be able to perform another experiment tonight in my ongoing efforts to find it!

Dusk at the Island Lake boat launch. My tripods are being prepared for their night’s work.

Nightscape Odyssey
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Rainier by Moonlight

Rainier by Moonlight
Mount Ranier National Park, 19 August 1999
Nikomat with 20mm lens at f/5.6
30 minute exposure on E200 push-processed +2 stops

I am told it is unusual to see the top of Mount Rainier.  The generally overcast skies of the region and the immensity of the mountain usually guarantee that clouds will somewhere get in the way of the view.  On this day however, the sky had been clear.  It stayed clear while the sun set, and as the glow of twilight was replaced by the feeble illumination of a young moon, I worked my way up the mountain’s shoulder to this site, aptly named Reflection Lake.

My daytime explorations had found this lake, but the surface had been broken everywhere by wind ripples.  Now the air stilled and the water became stable enough even for a time exposure of the mountain’s reflection.  I wanted to include some startrail features in this picture, but it is an awkward choice:  if the shutter is open too long, the moon would wash out the sky and the trails would be lost.  Too short, and the stars do not make sufficiently long marks.  This was my guess, 30 minutes, a balance between starlight and skylight.

This picture also answers the question, “what color is the sky at night?”  Maybe nocturnal creatures can see in color at night, but we don’t.  The moon lights up the world, including the sky, with reflected sunlight.  The same physics applies, just at lower levels of illumination, and so the sky is blue!

A few cirrus clouds stream past in the distance, but they’re not enough to keep the brightest stars from showing.  Four of them above and to the left of the mountain peak are the bowl of the Big Dipper, each bluish except for the brightest star in the constellation, Dubhe, a distinct orange color.

The moon set shortly after exposing this picture.  Its low angle is apparent from the long shadows on the distant snowfields.  My time in Rainier Park would end the next day, but this was a remarkable evening to finish my visit.