To create a successful result requires a composite approach - removing noise from the key areas where it is obtrusive but leaving the areas with fine detail untouched or lightly processed. Judge for yourself how successful the technique has been by examining the image below with its ‘before’ and ‘After’ versions. An enlargement has to be used because the differences are not visible on a small low resolution web image. Area where the noise reduction has been strongest are: the sky, locomotive cab front, buffers and lower valence.
(NOTE: it may be necessary to hold your mouse pointer over the image for a few seconds to allow the web browser to change the picture)