This GIMP (GNU) tutorial demonstrates how to create my absolute favourite effect, a Sabattier Solarisation Photo conversion, using GIMP’s Adjustment Curves Command. To work along, you are welcome to download the Start Image I am working with Here. Unzip the file and open the image onto GIMP’s workspace.
The Curves Command is the most sophisticated tool for changing the colour, brightness, contrast or transparency of the active layer or a selection. While the Levels Command allows you to work on Shadows and Highlights, the Curves Command allows you to work on any tonal range. It works on RGB images.
Photographs will always react uniquely. The following steps are perfect for my Start Image. When working with your own, it’s therefore important to tweak the Adjustment Curve, until you are happy with the Sabattier skin tone result.
Add Colour To Sabatier Skin Tones
Launch GIMP & Organise Its Workspace & Palettes
You can quickly Undo a step at any time by pressing Ctrl then Z. Alternatively, click a previous Undo History snapshot - Windows then Dockable Dialogues then click Undo History. In addition, to Zoom in (or Zoom out) of your image; from the top menu choose View then select a Zoom Tool from the subsequent drop-down list.
Open your choice of Start Image onto GIMP’s workspace - File then Open - Ctrl then O.
Ensure the Layers and the Undo History Palettes are visible, and then drag them into position over your workspace - (Windows then Dockable Dialogues - then click Layers and Undo History).
Colourised Sabattier Note
If you would like colour in your Sabattier effect, then skip Chapter 2’s Desaturate step, and move straight onto Chapter 3.
Now, from the top menu, choose Colours then choose Desaturate. And from the subsequent Desaturate dialogue box, enter the following Luminosity setting, and then click OK.
You are looking to create the following loosely constructed M-curve.
Now, from the top menu, choose Colours then choose Curves. Then grab the Black Point (illustrated below-left) and drag it all the way to the top of the Curves Graph - as demonstrated below-right.
Do NOT click OK until you reach Chapter 13.
Your image will be Pure White - as illustrated below.
Now, left-click to add a Point in the centre of the Horizontal Adjustment Curve.
Then left-click over the Point and drag it all the way to the bottom - then left-click to permanently attach the Point - as illustrated below.
Your image will resemble the following.
Now, click a Point over the upper left-side of the Curve - (near the top) as illustrated below.
Then drag the Point all the way to the top.
Now, grab the very first applied Point, (extreme top-left, as highlighted below).
And drag it all the way to the bottom of the Graph - as illustrated below.
This darkens your image.
It’s time to grab the Point, (highlighted below); and move it, so to bend the curve into a soft arc, as illustrated below. In order to find the best position, keep looking at your image, and see how it changes as you move the Point.
Now, click a Point over the right-side Curve - as illustrated below.
Then grab the Point and bend the Curve upwards, slightly.
It’s time to grab the Top right-side Point. Now, drag the Point all the way to the bottom - as illustrated below.
You must ensure the following bottom-left Point is positioned tight in the bottom-left corner, as illustrated below.
Individual images will always display their tones uniquely, therefore, be prepared to
experiment. Additionally, add as many Points as you like, and very gently, move the
curve to see how it effects your image. When utilising my Start Image, this type of loose M-curve, changes the image to the following.
Congratulations, your Sabattier effect is very nearly complete - as illustrated below
For my final Sabattier affect, I clicked three additional Points along the straight lines - then moved each Point slightly to the left, or to the right.
Moving a Point, even very slightly, will greatly change your image’s appearance. Therefore, move the Adjustment Curve in very small increments, and keep looking at your photograph, as you work.
12/ How To Save Your Sabatier Curve As A Preset
From the top-right of the Curves dialogue box, click the following Add settings to favourites (plus symbol) tab.
Now, from the subsequent Add Settings to Favourites dialogue box, type in a unique name for your newly created Sabattier Preset, and then click OK.
Look at your Start Image, and if you are happy with your final result, click OK to commit the change. (If you are not happy with the result, adjust with the Points until you see a result that suits your requirements).
From the top menu, choose Filters then choose Enhance and then choose Unsharp Mask. Now, from the subsequent dialogue box, enter settings of your choice, and then click OK.
Congratulations, your Solorised Sabattier Conversion is complete, and is ready to Optimise and Save.
Wendi E. M. Scarth. Top Of Page.