How do I create a disabled icon from an enabled one

I have a bunch of icons, and I need开发者_开发技巧 to create grayed versions of them to be used when the corresponding command is disabled. How can I do that in an easy way, preferrably using GIMP since that is the only graphics program I have installed?

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You could try in GIMP, Colours -> Desaturate

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My usual in GIMP is to ensure the image is in RGB mode (Image->Mode->RGB) and use Colors->Hue/Saturation, changing the Saturation down to -50 and the Lightness up to 50.

If there is a color still prominent in the disabled image, try also adjusting the Lightness up on one of the Primary Colors in the same dialog.

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Just for the sake of documenting -If you don't have GIMP, you can use Microsoft Office (Word or PowerPoint).

1. Add the original Enabled (color) icon.

2. Go to the 'Picture Tools' menu and press on 'format' > 'Color' > 'Color Saturation = 0%'

3. Save the icon - Right mouse click - 'Save as Picture'