GIMP :: General Color Enhancement / Sharpening

i was curious as to which sharpening/color correction techniques this photographer used to result in such a perfect photo. more specifically, i'd love to learn how he managed to make the blue halter strap almost shimmer and pop out of the image and his face a beautiful, warm and rich coffee color.

i attempted to recreate his enhanced image with the original, but fell slightly short in a few areas. i did eventually manage to get a similar look by simply adjusting input levels and sharpness, but had the toughest time making his head and all the fine details on it really "pop" AND "glow".

i basically increased the black input levels a bit to saturate and bring life to the image, but that resulted in the face and halter also darkening.

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