convert a layer to greyscale

[metulburr]

Every time i need to make a layer greyscaled, i need to load the layer as a whole new project, Image -> Mode -> greyscale, then convert back to RBG. Export it. Then load that image as a new layer to my project.

Can i simplify this more to just convert a layer to greyscale?

[Ofnuts]

Colors>Desaturate with three standard choices of color conversion, or, if you feel more adventurous, Color>Components>Channel mixer (and tick the "Monochrome" check box). In addition to working in a single layer, they will also take the selection in account.

<pedantic>Either choice gives you a gray layer (3 bytes per pixel, with R=G=B) but not a grayscale one (one byte/pixel)</pedantic>

[rich2005]

It is worth mentioning this article

http://blog.patdavid.net/2012/06/true-ps...-gimp.html

and if you read through it, the referenced script.

[Ofnuts]

Also, the weird recipe:

• set the bucket-fill tool to "Saturation" mode
  
• bucket-fill the layer with white
  

Why it works:

• Alongside the usual RGB model, another possible color representation model is HSV (Hue, Saturation, Value), saturation  being how "colored" things are.
  
• By setting the tool to "Saturation" mode, only the saturation of the painting color is used, in other words in each pixel, RGB is convert to HSV, S is set to 0, and HSV is converted back to RGB.
  
• And removing the saturation is one way to make everything gray.