Tag Archives: #inversion layer

NECR 3476: Orange Locomotive in Winter Light.

The combination of snow on the ground, very cold temperatures, and low light make for excellent photographic conditions, if you can bear to be outside.

I exposed this view of New England Central 3476 shortly after sunset in Palmer, Massachusetts.

NECR 3476 has a complicated history. Today it may be considered to be a SD40M-2. Originally an General Motors Electro Motive Division  SD45 built for Southern Pacific Lines affiliate Cotton Belt, it was remanufactured in the 1990 which transformed it from 3,600 hp machine (as powered by 20-cylinder 645-diesel) into a 3,000hp machine  (with 16-cylinder version of the EMD 645-diesel) while retaining the tapered (or ‘flared’) radiator intake vents at the back the of locomotive that were characteristic of EMD’s higher horsepower designs.

The snow reflects light from below, thus providing greater illumination of shadow areas that under ordinary conditions would be underexposed at this time of day.

Cold temperatures and clear overhead conditions result in a inversion effect, which traps particulates and other airborne impurities that acts as a light filter resulting in a scene with more red and magenta spectrum than normal.

This effect is intensified at sunset because the sunlight has to pass through much greater amounts of polluted atmosphere because of its relative angle to the ground.

To make the most of these lighting conditions, it helps to set the camera white balance to ‘daylight’, since ‘auto white balance’ while tend to cancel out the effect of the rosy lighting conditions.

Tracking the Light Posts Daily.