The Gimp

About the class

Oso Says "Take the Gimp Class!

April, 2005 was the first time MNR offers a class on the Gimp at Free Geek, but it's far from the first time he's taught the subject. The Gimp is the image editing software distributed on FreekBoxes - and used by all kinds of people to make cool pictures. This is an introductory-level class, and should be accessable to anyone who has mastered the material taught in the FreekBox Adoption Class.

Related Links

From the project's web site, gimp.org:

• Main page
• screenshots
• documentation
• public domain images

Class 1: Starting and Selections

right-click to download today's suggested image

• Finding and starting the Gimp
• Navigating the Gimp
• Opening files, Saving Files
• Freegeeks - Use Offline storage! Classroom machines are wiped clean every evening.
• Help! Using context sensitive help
• Palettes: Tools & Layers, (but not Channels or Paths)
• Making selections
• Dealing with Floating Selections

Something fun - change the color of the background.

1. use the elliptical select tool to select the earth in today's suggested image
2. float the selection
3. convert the selection to a new layer
4. change the foreground color (click on the black box in the tool palette)
5. add a new layer with a colored background (shift - new layer)
6. move the layers so the colored layer is underneath the earth

Class 2: Color select and Magic wand

Right-click to download today's suggested image

• Brief review
• Resizing images, resizing selections
• Color Select Tool
• Magic Wand
• Something fun - Float the rocket or the jellyfish (right click on the link to download)

1. open today's suggested image
2. open the rocket or jellyfish
3. use the layer palette to add an alpha channel how to do it
4. Remove the background of the rocket or jellyfish by clicking on the background with the magic wand or color selection tool. (hint - the rocket is easier)
5. drag the layer (from the rocket or jellyfish layer panel) into the space cloud image

Class 3: Edges, tools, fills, paths

Right click to download today's suggested image

• Edge Select
• Move, Rotate, shear, perspective & flip
• Fill, Gradient, pattern paint
• Quick mask & save to path. (tutorial on quickmask)
• path to selection
• Manipulating Selections
• Filters

Something fun - isolate Rosie from the background

1. Use the edge select tool, save to path and quickmask to create a selection around Rosie
2. duplicate the background
3. Select and float Rosie to a new layer. Turn off her visibility
4. use the motion filter on the duplicated background
5. Turn the "floated" version of Rosie back on.

Class 4: animations

An example of GIMP animations

Today's image (warning, 4 megabytes) contains XCF files for use with GIMP

• Animations

Tutorial on Gimp Animation

Class 5: paths

Right click to download this sample image

• When you open this document, be sure to "Import Paths"
• The Paths dialog
• Selection to path
• Path to selection
• Stroking a path
• The Path Tool
  • getting the path menu
• Path from text

Class 6: Common tasks

• Red eye removal
• Saving for the web
• Reducing the size of an image

Class 7: Fixing Images

A crappy photo taken with a cell phone. Right click to save this to your desktop

• [Color Tools - Levels ] This tool can be used to adjust colors. It will be easier to understand this tool if you understand [histograms].

  * Use the Black Eyedropper to pick a black point.
  * Use the White Eyedropper to pick a white point.
  * Adjust mid-tones using the slider.
  * Color cast can be adjusted using the channels and eyedroppers

• [Enhance - Unsharp Mask]
• [Here is a good tutorial on color correction with gimp]

A less-than-stellar photo. Right click to save this to your desktop

The same photo after adjusting color and sharpening

If we wind up talking about color correction, you're going to need a color wheel