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The Nikon D5100 has an HDR mode that can be activated when it's set to record JPEG files. In this mode the D5100 takes two images with different exposures in quick succession and merges them into one image with more shadow and highlight detail. The exposure differential can be set manually to 1, 2 or 3EV. Alternatively the D5100 can be set to decide the exposure difference automatically.
Although there is some haloing visible around high contrast edges, it's good to see that the HDR effect is fairly subtle. It could prove useful.
HDR off (Click here to see the full resolution image)
3EV HDR (Click here to see the full resolution image)
Auto HDR (Click here to see the full resolution image)
HDR off and exposure compensation set to -0.7EV (Click here to see the full resolution image)
HDR 3EV and exposure compensation set to -0.7EV (Click here to see the full resolution image)