Nikon D5100 Reference Manual page 35

Create a copy in which only selected hues appear in color.
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Select Selective color.
Highlight Selective color in the retouch menu
and press I_ to display a picture selection dialog.
Select a photograph.
Highlight a photograph (to view the highlighted
photograph full frame, press and hold the
button). Press _) to select the highlighted
photograph and proceed to the next step.
Select a color.
Use the multi selector to position the cursor
over an object and press o-n (_:[) to select the
color of the object as one that will remain in
the final copy (the camera may have
difficulty detecting unsaturated colors;
choose a saturated color). To zoom in on the
picture for precise color selection, press _.
Press ql_ to zoom out.
AE-L 0-,I (AF-L) button
Selectedcolor
Highlight the color range.
Rotate the command dial to highlight the color
range for the selected color.
Color range
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