Using Neutral Density Filters

One of the biggest challenges landscape photographers face is that the sky is often much lighter than the landscape below. The difference in brightness can be equivalent to several stops and the level of contrast can extend beyond the sensor’s dynamic range. Consequently, if you meter correctly for the sky, the foreground will be too dark; but if you meter for the land, the sky will be overexposed and highlights washed out. Filtration is the only in-camera method of balancing the light in unevenly lit scenes.
Graduated ND filters are half clear, half coated; with a transitional zone where they meet. By aligning the transitional zone with the horizon, only the sky is affected by the filter’s ND coating. Doing so allows photographers to ‘hold back’ the sky in order to balance the contrast in light between sky and foreground. By using a ‘grad’, it is possible to bring the entire scene within the sensor’s dynamic range – ensuring detail is retained in both shadow and highlight areas.

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