Meet the GIMP #34: Full Control! - Monochrome conversion (3)
In this last episode (for now…) about monochrome con- version I show you a way to get full control over the process of making a monochrome image.
I “decompose” the RGB image into three layers, each containing one of the three colour channels.
By adjusting the opacity of the three layers I mix the channels as with the channel mixer. But I have the full image as “preview area” and can change the values as long and often as I want.
Each of the layers can be further modified with the curves tool, other tools or partially masked off. Don’t forget to make a safety copy of the layer.
The image on the top of this page was done in this way. It’s an enhanced version of the one I showed in the video. I have added a masked red layer for the background and a bit red layer for all of the image. This version is in the files for downloading - just two layers more than in the video.The challenge
You can use this technique in the current challenge. Do a monochrome conversion with GIMP, post the image in the meetthegimp.org photogroup at 23 and be sure to use the tag “mtg-monochrome”. The challenge ends March 31 1600GMT and I’ll draw a winner by random choice.The TOC
02:50 The leaf picture again
03:26 The colour channels
06:26 The colour layers
08:00 Mixing the layers
09:20 Understanding the layer mixing numbers
10:15 Examining the layers
11:57 Adjusting the layers
13:00 - Curves on the blue layer
15:00 - And a layer mask
18:50 The Black and White Challenge
19:30 - Slide show
22:36 The web-site
24:49 The End
TOC made by paynekj