Aspen at Base of Lichened Boulders & Cliffs; Puma Hills, CO.


Aspen at Base of Lichened Boulders & Cliffs





This 4x5 original slide looks best cropped slightly to a squarer 6:5 aspect ratio.
GPS location: 39° 04 5/6'N, 105° 31 5/6'W; 9350 feet altitude.

This is an example of a slide that was only salvageable using digital scanning contols. The scene was rather dimly lit (some 6-7 stops below normal sunlight) and I stopped down beyond f/22 to get nearly maximum depth of field. This was exacerbated 2 more stops by also using both a center filter and a light balancing filter (to compensate for the bluish skylight illumination).

So the exposure time -- or should I say time exposure? -- was 10 seconds. Of course this long an exposure is only possible with subject matter that isn't moving, meaning no wind when you're working outdoors; fortunately it was dead calm. Color films aren't designed for this long an exposure: the three different light sensitive layers have different reciprocity failures, so the colors go way out of balance and the resulting slide has a strong color cast. But using all the controls available on the scanner, the original "look and feel" of the scene could be recovered.

This is an example of some of the best super-wide angle, large format work I think I've done. A 75mm lens was used. Hence the necessity of using a center filter. This means the original scene was very "tight", with the nearest rocks only some 6-8 feet away, and the nearer branches hardly much more than a foot or eighteen inches. Hence the need for a large depth of field even with such a short focal length lens. The horizontal angular field of view is 72½°.

To the extent I could fine tune the composition by moving the camera, mostly right or left a little bit, this was done to "frame" the vertical streaks and markings on the rocks, both right of center and towards the upper left, in the openings between the trees. Unfortunately this left the bright orange lichen mostly hidden behind the tangled mass of small branches, but oh well. If I had it to do over again, I'd move the camera another inch or two to the left; this would have moved the large tree trunk at farthest left towards the right relative to the more distant cliff faces near the top, so its left edge wouldn't line up so much with the left edge of the rocks.

The native resolution of the original digital file is extremely high (90 MP). This 495 KP version for electronic display thus represents a reduction in area of 185x.


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